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Home My WebLink About05-Stormwater Design Report - Combined (2025-05-26) Rocky Mountain Flats – Stormwater Design Report Page 1 September 15, 2025 TABLE OF CONTENTS INTRODUCTION ............................................................................................................................................. 2 Project Overview ....................................................................................................................................... 2 Existing Site Conditions ............................................................................................................................. 2 Proposed Site Improvements ................................................................................................................... 3 HYDROLOGY AND HYDROGEOLOGY ............................................................................................................. 4 Design Storm Rainfall & Runoff Calculation method ................................................................................ 4 Hydrogeology ............................................................................................................................................ 6 EXISTING STORMWATER DRAINAGE CONDITIONS ....................................................................................... 6 EXIStiNG DRAINAGE CONDITIONS ............................................................................................................ 6 EXISTING DRAINAGE FACILITIES ................................................................................................................ 7 PROPOSED STORMWATER DRAINAGE SYSTEM ............................................................................................ 8 DRAINAGE SYSTEM Components .............................................................................................................. 8 SYSTEM SIZING Considerations ................................................................................................................. 9 OFFSITE RUNOFF ..................................................................................................................................... 11 Groundwater considerations .................................................................................................................. 13 APPENDIX Appendix A ................................................................................................................... Drainage Basin Maps Appendix B ..................................................................................... Stormwater Storage Facility Calculations Appendix C ........................................................................................................................ SSA Model Results Appendix D ........................................................................................................... Geotechnical Investigation Appendix E ................................................................................................................. Stormwater O&M Plan Appendix F ................................................... Stormwater Design Report for The Homestead at Buffalo Run Appendix G ................................ Administrative Waiver of Groundwater Separation to Stormwater Facility Rocky Mountain Flats – Stormwater Design Report Page 2 September 15, 2025 INTRODUCTION PROJECT OVERVIEW The purpose of this report is to detail the stormwater management design for the proposed Rocky Mountain Flats affordable housing project. The proposed project will develop the 10.16-acre site with extensions of the city street grid, a large city park, an open space area, and two apartment sites containing 296 dwelling units between 3 buildings. The property is legally described as N ½ S ½ SW ¼ SW ¼ of Sec. 23, T2S, R5E, PMM, City of Bozeman, MT and the current address for the property is 5532 Fowler Lane, Bozeman, MT 59715. Location Exhibit EXISTING SITE CONDITIONS The property currently contains a single-family home and several outbuildings, including a garage and an additional combo garage/ADU. These structures are generally situated on the west side of the site along Fowler Lane and the remainder of the property is open field that was historically in agricultural use. The property is primarily vegetated with a mix of grasses that are hayed annually, while the western portion of property around the homes is comprised of lawns, landscape beds and mature trees. The property generally slopes from south to north at approximately 1.5-2%. There are two irrigation ditch laterals that run parallel to one another and flow south to north along the east side of Fowler Lane. Historically the larger, western ditch was the main irrigation ditch along Fowler Lane and provided irrigation flows to many properties downstream of the project site. The smaller eastern ditch lateral primarily provided irrigation water to the properties immediately north of the project site. PROJECT SITE Rocky Mountain Flats – Stormwater Design Report Page 3 September 15, 2025 However, as part of the Buffalo Run project improvements to Fowler Lane, the main ditch was realigned to the western side of Fowler Lane starting south of the subject property. Additionally, as part of the Buffalo Run improvements both the ditches that run across the property were diverted to flow under Fowler at the north end of the property and into the new irrigation ditch on the west side of the road. The existing ditch sections on the east side of Fowler were then filled at the northern property line of the subject property. Sundog Ecological performed a wetland delineation in May 2025 and noted wetland fringes in the bottom of the ditches along the east side of Fowler Lane. No other wetland areas were identified on the site. The property is in the process of being annexed into the City of Bozeman with a proposed zoning designation of R-4 (high-density residential). The subject property is currently the southwestern most corner of the city limits of Bozeman and is therefore bordered by a mix of city and county properties. The property to the north is annexed into the city, zoned R-4, and is currently in the process of being developed into a multi-family apartment development known as Buffalo Run. The properties to the east of the site are also annexed into the city, zoned R-3, and are part of a single-family subdivision known as Meadow Creek Subdivision. A city park was complex was constructed along the eastern and northeastern boundaries of the project site as part of both Meadow Creek and Buffalo Run. The properties to the south and west are currently unannexed county properties that are in agricultural use and are zoned AS (Agricultural/Suburban). The property is bounded on the west by Fowler Lane, which is built to a City of Bozeman arterial street standard to the north of the property and transitions from a paved to gravel surface across the property frontage. Meah Lane and S. 31st Ave, both city local streets, intersect and dead end at the southeast corner of the property. Edgerton Ave and Gabriel Ave (also local streets) dead end at the northern property boundary. All of these street sections will either be widened or extended into the property as part of the proposed project. PROPOSED SITE IMPROVEMENTS Proposed infrastructure improvements for the project include extensions of the city street grid and extensions of the city water and sanitary sewer systems within the street grid. Fowler Lane will be widened across the project frontage to a city minor arterial standard. Meah Lane will be extended from its current location on the southeastern property corner, west to Fowler Lane. Edgerton Avenue and Gabriel Avenue will be installed across the property from their stubs on the north property line, south to Meah Lane. The existing irrigation ditches on the east side of Fowler Lane are proposed to be diverted west across Fowler Lane at the existing culvert south of the project site and into the larger ditch on the west side of the road. The ditch channels across the project frontage on the east side of Fowler will then be filled to accommodate a widened street section for Fowler Lane with boulevard and pedestrian amenities. The existing culvert at the north end of the project site that originally conveyed these ditches across Fowler Lane will either be removed or abandoned in place. An 18” dia. stormwater trunk main was installed within the Fowler Lane boulevard with the Buffalo Run improvements and was capped at the northern property boundary. This trunk main will be extended along Fowler with the project improvements to convey runoff from the Fowler Right-of-Way. The design intent behind this trunk main is explained in more detail in the “Proposed Drainage System” section of this report. Rocky Mountain Flats – Stormwater Design Report Page 4 September 15, 2025 The proposed development of the two apartment sites on the property will include 3 residential buildings with associated parking lots, open space areas, and landscaping. Since the site is proposed to be almost completely developed, the majority of the stormwater runoff from the proposed improvements will be conveyed to subsurface chamber systems beneath the proposed parking lots for runoff control of the minor storm event. Runoff from the major storm event will pond in the parking lots and open space areas for eventual infiltration into the retention systems. The storm systems that will drain the public right-of- way have been designed as separate systems from the systems for the private site improvements. HYDROLOGY AND HYDROGEOLOGY DESIGN STORM RAINFALL & RUNOFF CALCULATION METHOD In accordance with the City of Bozeman Design Standards and Specifications Policy (COB DSSP), stormwater runoff for the proposed project was analyzed for both the minor and major storm events. The minor storm that was analyzed was the 10-year storm, while the major storm was analyzed as the 100- year, 24-hour storm event. For this particular project, the Rational Method was chosen for the runoff calculation method. Since the Rational Method was being used, rainfall intensities for both storm events were determined from the following table (Table 6.5.2) from Chapter 6 of the COB DSSP. For the minor (10-year) storm event, the COB DSSP does not specify a set storm duration that needs to be used for determining peak runoff flow rates or runoff volumes. So, in order to choose a storm duration to analyze, a time of concentration path was determined for the individual drainage basins on the project site and the storm duration was assumed to be equal to the longest time of concentration path for that Rocky Mountain Flats – Stormwater Design Report Page 5 September 15, 2025 drainage basin. The intensity (inches/hour) for that corresponding time of concentration duration was then interpolated from Table 6.5.2. to determine the runoff rate and volumes. For the major (100-yr, 24- hr) storm event a rainfall intensity of 0.098 inches/hour was used from Table 6.5.2. The computer program Autodesk Storm & Sanitary Analysis (SSA) was used to model the stormwater runoff on the project site to determine the time of concentrations, peak runoff rates, pipe and inlet capacities, and 10-year design storm runoff volumes. The output results from the SSA model can be found in Appendix C for reference. In addition to SSA, spreadsheets were used to determine the runoff volumes for each drainage basin for the 100-yr, 24-hr storm event. The spreadsheets containing the runoff volume information can be found in Appendix B for reference. The following runoff coefficients (C-values) from Table 6.6.4 were used to represent various existing and proposed surface cover types in the stormwater model in accordance with the COB DSSP. Rocky Mountain Flats – Stormwater Design Report Page 6 September 15, 2025 HYDROGEOLOGY IMEG Corporation completed an initial geotechnical investigation on the subject property in December 2021 which included the excavation of 7 test pits and installation of 7 groundwater monitoring wells. IMEG returned to the site in January 2025 to conduct an additional investigation that involved 7 exploratory soil borings. The test pits ranged in depth from 7’-8’ below ground surface (bgs) while the borings ranged from 9’-25’ bgs. The full geotechnical investigation can be found in Appendix D for reference, but the following general soil horizons were observed during the investigations: - Silty Clay Organic Soil (topsoil): 0’-1’ bgs - Sandy Lean Clay: 1’-3’ bgs - Poorly Graded Gravel: 3’-25’ bgs The property is in an area of town that is known to have a high seasonal groundwater table. The water table fluctuates by several feet throughout the year, but is generally observed to peak in the spring from snow melt in the surrounding valley and mountains, and again in the summer/fall from flood irrigation of the surrounding agricultural properties. IMEG performed groundwater monitoring of the 7 wells from April to August 2022 and their results indicate that groundwater peaked in early June at depths of approximately 2.5’-3.5’ bgs. The groundwater monitoring well map and a table of the monitoring results can be found at the end of the geotechnical investigation in Appendix D. These peak groundwater depths were converted to elevations and were used to create a peak groundwater surface in AutoCAD during site design. This surface was then used to estimate the peak groundwater elevation in areas of the site where stormwater facilities are proposed. The Montana Post- Construction Storm Water BMP Design Guidance Manual recommends 3 feet of separation between seasonal high groundwater levels and stormwater retention/detention facilities. Given the high levels of groundwater on the project site, this recommendation is not feasible, so the stormwater facilities have instead been designed with 2 feet of separation from the seasonal high groundwater table as outlined in the COB DSSP. There are several storm facilities at the north end of the project site that do not meet this 2’ minimum separation requirement. An explanation of why these storm facilities cannot meet the 2’ separation requirement is provided in the “Proposed Stormwater Drainage System” section of this report. EXISTING STORMWATER DRAINAGE CONDITIONS EXISTING DRAINAGE CONDITIONS As mentioned previously the existing property is primarily densely vegetated with grass and drains to the north at 1.5%-2%. Other than the existing ditches along Fowler Lane there are no other watercourses on the property to concentrate runoff to specific outfalls, so the majority of the property is estimated to sheet flow onto the property to the north. The pre-development runoff for the property was analyzed by splitting the property into 4 pre- development drainage basins based on existing site topography. The western most basin (DB PRE 1) includes the portion of the site around the existing structures and Fowler Lane that drains into the irrigation ditches on the east side of Fowler. This is the smallest of the 4 predevelopment basins. The boundaries for the other 3 basins then generally align with Edgerton Ave and Gabriel Ave, which allowed for predevelopment runoff flow rates and volumes to be determined for each of the areas between these roads. Due to the small amount of existing impervious cover and relatively gradual existing grades on site, the pre-development runoff rates were minimal. However, since the pre-development drainage basins Rocky Mountain Flats – Stormwater Design Report Page 7 September 15, 2025 are fairly large, the runoff volumes for the 10-year and 100-year storm events were not insignificant. They are summarized in the table below and the pre-development drainage basins are detailed on the Pre- Development Drainage Area Map in Appendix A. Table 1: Pre-Development Drainage Area Summary For projects such as this the typical stormwater design methodology would be to compare pre- development runoff rates from the project site to proposed post-development runoff rates to ensure that post development discharge does not exceed pre-development rates. However, the stormwater design for the Buffalo Run development immediately north of the project site does not appear to account for pre-development run-on from the Rocky Mountain Flats project site. Additionally, the Buffalo Run development has several large apartment buildings constructed close to the property line, so discharging treated post development runoff to the north at pre-development rates would risk inundating buildings in Buffalo Run. Therefore, although pre-development runoff rates total 5,848 CF for the 10-year storm event and 17,468 CF for the 100-year Major storm event, the majority of post development discharge is planned to be retained on the project site to avoid impacts to the property to the north. This is further discussed the “Proposed Stormwater Drainage System” section of this report. EXISTING DRAINAGE FACILITIES There are very few existing drainage facilities to review as part of the proposed development. As mentioned previously, the existing irrigation ditches along the east side of Fowler and the irrigation culvert across Fowler Lane at the north end of the project site will be abandoned as part of the development. The existing ditch on the west side of Fowler will not receive any runoff from the proposed improvements since all Fowler Lane runoff will be captured with new or existing storm facilities and conveyed to the stormwater trunk main in the Fowler Lane right-of-way. This existing trunk main is analyzed in the “Proposed Stormwater Drainage System” portion of this report, and the Buffalo Run Stormwater design report that includes the initial design of this trunk main is included in Appendix F for reference. Intensity (in/hr) Peak Flow Rate (cfs) Runoff Volume (cf) Intensity (in/hr) Peak Flow Rate (cfs) Runoff Volume (cf) PRE 1 0.39 0.95 0:30:40 NONE 1.36 0.50 924 0.098 0.04 3,164 PRE 2 0.21 3.00 1:42:46 NONE 0.47 0.30 1,845 0.098 0.06 5,371 PRE 3 0.17 4.64 1:37:26 NONE 0.50 0.39 2,304 0.098 0.08 6,684 PRE 4 0.17 1.56 1:42:33 NONE 0.48 0.13 775 0.098 0.03 2,250 Total 10.16 5,848 17,468 Basin 10 year Storm 100 year - 24 hr StormTime of Concentration (hr:min:sec) Area (acres) Weighted Runoff Coefficient Treatment Facility Rocky Mountain Flats – Stormwater Design Report Page 8 September 15, 2025 PROPOSED STORMWATER DRAINAGE SYSTEM DRAINAGE SYSTEM COMPONENTS Stormwater management for the proposed development will be handled by a network of roof downspouts, curb, and concrete valley gutters to convey runoff to the proposed storm sewer system. This storm sewer system will be comprised of inlet structures and pipes that convey runoff to a variety of retention facilities. The majority of the retention facilities are designed as ADS Stormtech® SC-160LP underground infiltration chamber systems, but several shallow retention ponds and boulevard swales are proposed as well. In order to accurately model the proposed system, the development was broken into a series of post- development drainage basins so that the storm sewer system and runoff control facilities could be accurately sized. Each drainage basin was assigned a time of concentration from the most remote point in the basin using the TR-55 method and this time of concentration was used to determine peak runoff rates and volumes for each basin. A post development drainage basin map is included in Appendix A for reference, and a list of the various sub drainage basins and their characteristics is included in Appendix C. For the most part, stormwater runoff generated from the proposed city road network was separated into separate drainage basins from the site’s private improvements. Runoff from the road network will also be directed to separate retention facilities from those that receive runoff from the site’s private improvements. Although all proposed stormwater systems will currently be maintained by the property owner, this separation of facilities is intended to allow the city to take over maintenance of the infrastructure related facilities in the future, if they choose. Stormwater Management easements will be dedicated over the storm network and retention facilities that receive runoff from the public roads to allow for perpetual access to the systems. Initial Conveyance System: The majority of runoff from the proposed public and private improvements will be conveyed to the storm sewer system via concrete integral curb and gutter along the edges of the streets and parking lots. This curb and gutter was designed based on the City of Bozeman Standard Drawing Detail No. 02528-1. In accordance with the COB DSSP, the street gutters were designed with a minimum slope of 0.60% and curb inlets were spaced to ensure that gutter flow in the streets did not overtop the curb during the minor storm event. Storm Sewer System: The storm sewer network for the private site improvements is comprised of pre- cast concrete curb inlets and manholes, ADS Nyloplast® drain basins and inline drains, and ADS HP storm pipe that conveys runoff to the Stormtech chamber systems. The storm sewer network for the public street rights-of-way is also comprised of pre-cast concrete inlets and manholes, but the storm sewer piping for these public systems is either SDR-35 PVC pipe or RCP pipe, per city standards. Curb inlets placed at sag curves (low points) in city streets were designed with a 50% clogging factor per the COB DSSP. Retention Ponds: Three retention ponds have been designed to retain runoff from portions of the public street right-of-way. These ponds have been sized to retain runoff from the 10-year storm event with a maximum water storage depth of 1.5 feet. The ponds will have 4:1 maximum side slopes and will be finish graded with topsoil and seeded for easy maintenance. Chamber Systems: The proposed underground infiltration systems will be StormTech SC 160 LP chamber systems. These systems are plastic arched-shaped chambers with washed rock bedding/backfill that have Rocky Mountain Flats – Stormwater Design Report Page 9 September 15, 2025 been sized to provide adequate stormwater retention volume of the minor storm event. After the design storm, runoff within the chamber systems will infiltrate into the ground. The area underneath the chamber systems will be excavated down to native gravels and backfilled with well-draining material to ensure the systems have adequate infiltration. The DEQ infiltration rate for gravel (2.6 inches per hour) from Circular DEQ 8, Appendix C, Table 2 was used for native gravels and applied to the system footprints to ensure that infiltration of the design storm events within 72 hours was possible. Appendix C of Circular DEQ-8 states that the infiltration rates provided can be increased by 50% with the use of sediment reducing pre-treatment facilities. Since all the chamber systems are designed with a weir to divert the initial flow from any storm event to a lined Isolator® Row for pre-treatment and sediment collection, the 2.6 in/hr infiltration rate was increased by 50% to 3.9 in/hr for the chamber infiltration calculations. This infiltration rate is still believed to be conservative since infiltration tests on native gravel in Bozeman on other projects have produced infiltration rates that are significantly higher than 3.9 in/hr. SYSTEM SIZING CONSIDERATIONS In accordance with the COB DSSP, the stormwater management system is designed with the minor and major design storm events in mind. As mentioned previously in the Existing Stormwater Drainage Conditions portion of this report, the only existing water conveyance facility feature that can receive runoff from the project site is the 18” storm sewer trunk main in the Fowler Lane right-of-way. Since there is only one viable receiving body for stormwater runoff and the Buffalo Run development to the north did not account for pre-development runoff from the project site, all stormwater runoff facilities had to be sized as retention facilities instead of detention. Therefore, the storm system is modeled and sized to convey peak flow rates from the 10-year design storm under open pipe flow conditions, and retain 100% of the 10-year runoff volume within the proposed retention facilities. Since the proposed facilities are retention and are not being discharged off site to downstream water bodies, calculations for treatment of the water quality volume from the first 0.5” of rainfall was not necessary. The system is also modeled to convey peak flow rates from the 100-year design storm under surcharged pipe conditions (if necessary) and analyze potential ponding and flooding from the 100-yr, 24-hr runoff volume. Summary tables of the proposed retention facilities for the 10-year and 100-year storm events are provided in the following sections, and a summary of the storm sewer system (structures and pipes) during both storm events is provided in Appendix C. Minor Storm Event As explained previously, the COB DSSP does not specify a set storm duration that needs to be used for determining peak runoff flow rates or runoff volumes for the minor (10-year) storm event. So, in order to choose a storm duration to analyze, the storm duration for each drainage basin was assumed to be equal to the longest time of concentration path for that drainage basin. The intensity (inches/hour) for that corresponding time of concentration duration was then interpolated from Table 6.5.2. to determine the runoff rate and volumes. It should be noted that since storm durations with the rational method are typically 5-20 minutes, this method results in a storm duration for the 10-year storm event that is generally significantly shorter than Rocky Mountain Flats – Stormwater Design Report Page 10 September 15, 2025 the 2-hr duration that was required under the previous city standards. This shorter duration results in a higher rainfall intensity (per Table 6.5.2) and therefore larger peak flow rates, but results in a significantly smaller runoff volume than the previous standards required with the 10-yr, 2-hr storm. However, since the new design standards require runoff control to be provided for the 100-yr, 24-hr runoff volume, many of the proposed stormwater facilities ended up being sized larger than they would have been for the 10- yr, 2-hr storm under the previous standards. Major Storm Event As explained previously, the new COB DSSP requires runoff control considerations to be made for the major (100-yr, 24-hr) storm event in addition to the 10-year 24-hr storm event. In order to determine the 100-yr runoff volume a rainfall intensity of 0.098 inches/hour was used from Table 6.5.2. Runoff volumes for this storm event were calculated for each drainage basin using spreadsheets and are provided in Appendix B, while peak flow rates from the 100-year event in the various conveyance facilities are provided in Appendix C. In general runoff from the 100-year event will be captured on site by a combination of upsizing the proposed retention facilities and allowing for ponding in the parking lots and open space areas around the retention facilities. In accordance with the COB DSSP, the ponding areas were sized so that ponding elevations remained 1 foot below the finish floor elevations of adjacent buildings. Since several of the 10 Year Storm Runoff Summary Table STORM FACILITY PEAK INFLOW (cfs) 10-YR VOLUME REQUIRED (CF) VOLUME PROVIDED (CF) CONTRUIBUTING SUBBASINS STORMTECH CHAMBER #1 4.12 1,945 2,612 DA 1A, DA 1B, DA 1C, DA 1D STORMTECH CHAMBER #2-1 1.69 512 1,761 DA 2A STORMTECH CHAMBER #2-2 2.57 777 1,544 DA 2B, DA 2C STORMTECH CHAMBER #2-3 0.61 186 579 DA 2D STORMTECH CHAMBER #3 3.33 2,087 3,044 DA 3A, DA 3B, DA 3C, DA 3D STORMTECH CHAMBER #5 1.20 368 1,611 DA 5A, DA 5B STORMTECH CHAMBER #7 1.81 536 1,473 DA 7A, DA 7B STORMTECH CHAMBER #8 0.35 109 706 DA 8B STORM SYSTEM #4 (LID POND) 0.93 399 437 DA 4A STORM SYSTEM #6 (RET. POND) 1.27 403 2,393 DA 6A, DA 6B, DA 6C STORM SYSTEM #8 (RET. POND) 0.61 390 1,566 DA 8A1, DA 8A2 STORM SYSTEM #9 (RET. POND) 0.98 787 954 DA 9A, DA 9B, DA 9C, DA 9D STORM SYSTEM #10 (SWALE) 0.19 57 64 DA 10 STORMTECH CHAMBER #R-4 2.30 760 1,210 B-1, B-1A, B-2, B-2A STORMTECH CHAMBER #R-5 1.75 722 1,454 C-1, C-1A, C-2, C-2A 10 Year Storm Offsite Runoff Summary Table STORM FACILITY PEAK INFLOW (cfs) 10-YR VOLUME REQUIRED (CF) VOLUME PROVIDED (CF) CONTRUIBUTING SUBBASINS NONE 0.13 38 NA 31st Ave NONE 0.22 117 NA OFF SITE 1 BUFFALO RUN LID POND 0.08 24 NA DA F-EAST BUFFALO RUN HYDRODYNAMIC SEPARATOR 0.80 360 NA F-WEST A, 4B Rocky Mountain Flats – Stormwater Design Report Page 11 September 15, 2025 storm systems (such as System 1 and 5) are within the same parking lot, the ponding analysis for these areas had to account for runoff from multiple drainage basins ponding in the same parking lots. Therefore, the ponding analysis has been broken into several “overflow areas” as outlined in the below table. As illustrated in the table below, the total runoff volume from the combined drainage basins in these overflow areas was compared to the total provided retention volume from the systems and the surface ponding. As illustrated in the table, there are 4 areas where there is not sufficient volume provided on site to fully retain the 100-year storm event. However, in each of these areas the volume that would flow off-site is less than the pre-development runoff volume that would discharge off site in that area during the 100-year pre-development event. This is also illustrated in the below table. OFFSITE RUNOFF Drainage Area: Off Site 1 There are two small landscaped areas along the property line north of Buildings B and C that do not currently have downgradient stormwater facilities to capture runoff. These areas range in width from 8’ to 35’ off of the property line but are spread across 360‘ of property line, so concentrated flow of the runoff from these areas is not anticipated. The total runoff volume generated by these areas during the 10-yr minor storm event is 117 CF. Since this 117 CF of runoff will be spread across 360’ of property line, providing additional drainage features for these areas was not determined to be necessary. The adjacent property line is the low point between this development and the Buffalo Run development to the north, so runoff from these areas is expected to be concentrated along the property line and not create drainage issues near buildings or sidewalks. Fowler Lane As outlined in the Buffalo Run stormwater design report, the city intends to create a storm water trunk main along the east side of Fowler Lane to direct runoff from the Fowler Lane right-of-way north to a future regional stormwater facility. Part of the reason for this trunk main is that the large irrigation ditch along the west side of Fowler Lane will make it difficult for stormwater from the western half of the street right-of-way to be conveyed across the ditch to storage facilities in the future. The Buffalo Run development initiated this trunk main with the installation of an 18” dia. storm pipe in the eastern boulevard of Fowler Lane across their project frontage. According to the design report for that 100 Year Storm Runoff Summary Table OVERFLOW AREA CONTRUIBUTING SUBBASINS 100-YR VOLUME REQUIRED (CF) TOTAL VOLUME REQUIRED (CF) STORM FACILITY VOLUME PROVIDED (CF) TOTAL VOLUME PROVIDED (CF) OFF SITE RUNOFF VOLUME (CF) PRE DEV. RUNOFF VOLUME AT OUTFALL (CF) PRE DEVELOPMENT AREA DA 1A, DA 1B, DA 1C, DA 1D 12,077 STORMTECH CHAMBER #1 2,612 DA 5A, DA 5B 2,703 STORMTECH CHAMBER #5 1,611 Additional Ponding - Parking Lot 10,800 DA 2A 3,775 STORMTECH CHAMBER #2-1 1,761 DA 2B, DA 2C 5,670 STORMTECH CHAMBER #2-2 1,544 DA 2D 1,366 STORMTECH CHAMBER #2-3 579 DA 2E 540 OVERFLOW PONDS 2-1 & 2-2 4,630 DA 7A, DA 7B 4,169 STORMTECH CHAMBER #7 1,473 DA OFF SITE 1 573 None 0 Additional Ponding - Parking Lot 5,022 DA 3A, DA 3B, DA 3C, DA 3D 11,349 STORMTECH CHAMBER #3 3,044 DA 8B 792 STORMTECH CHAMBER #8 706Additional Ponding - Parking Lot 8,410 D DA 4A 2,395 2,395 STORM SYSTEM #4 (LID POND) 437 437 NA NA PRE 1 E DA 6A, DA 6B, DA 6C 3,345 3,345 STORM SYSTEM #6 (RET. POND) 2,393 2,393 952 5,371 PRE 2 DA 8A1, DA 8A2 1,949 STORM SYSTEM #8 (RET. POND) 1,566 DA 10 412 STORM SYSTEM #10 (Blvd Swales) 64 Additonal Ponding - Open Space 750 DA 9A, DA 9B, DA 9C, DA 9D 3,640 STORM SYSTEM #9 (RET. POND) 954 Additional Ponding - Park Area 572 PRE 1 PRE 3 PRE 3 PRE 3 PRE 4 0 6,684 N/A C 16,093 12,141 12,160 0 N/A A 14,780 15,023 15,009 G 3,640 1,526 2,114 2,254 F B 2,361 2,380 N/A0 1,084 Rocky Mountain Flats – Stormwater Design Report Page 12 September 15, 2025 project, the 18” pipe was sized to accommodate runoff from the future 100’ Fowler Lane ROW (62’ TBC to TBC) from Blackwood Road to the north end of their project site (approximately Kurk Drive). The Buffalo Run design placed the trunk main under where the future curb line for Fowler will be when it is widened to a 62’ wide street. The project provided interim storm ponds in the Fowler boulevard for the eastern half of the 38’ street section and provided a hydrodynamic separator (HDS) on the trunk main to treat runoff from the west half of the street section. This HDS was sized to treat the stormwater quality volume for future 62’ buildout condition of Fowler Lane from Blackwood Road to Kurk Drive. In keeping with this design intent, the 18” trunk main will be extended across the Rocky Mountain Flats project frontage and will maintain a slope of approximately 1.60%. At this slope the trunk main will have capacity of 14-14.6 cfs, while the runoff flowing through the pipe from the proposed Rocky Mountain Flats improvements will amount to only 1.05 CFS during the minor storm event. Runoff from the majority of the eastern portion of the Fowler right-of-way (DB 4A) will be conveyed in the eastern curb line of Fowler to a proposed LID retention pond in the Fowler boulevard (Storm System #4). During the major storm event runoff from this pond that exceeds the pond’s storage capacity would discharge into the 18” trunk main through a slotted grate on structure ST 4-1. Runoff from the southernmost portion of Fowler and Meah Lane will be collected in structure ST 4-2 which is a curb inlet on top of the trunk main. Runoff control is not proposed for this inlet, so runoff from this system will be conveyed to the hydrodynamic separator (HDS) on the trunk main in Buffalo Run for water quality treatment. As explained in the Buffalo Run design report in Appendix F, this HDS was sized to treat the water quality flow rate from this portion of Fowler Lane. Similarly, runoff from the western portion of the Fowler Lane right-of-way will flow north on Fowler to a series of inlets installed with the Buffalo Run project. These inlets will convey runoff to the HDS. These inlets and their drainage basins were modeled with this project to confirm that they had sufficient capacity for the additional runoff from the Rocky Mountain Flats portion of Fowler Lane. Edgerton and Gabriel Avenues Both Edgerton and Gabriel Avenues are local street sections that were stubbed into the project site at the northern property boundary with the Buffalo Run development. Both streets will be extended south across the project site to intersect with Meah Lane. The Buffalo Run development accounted for runoff from the southern portion of Edgerton Avenue with drainage area R-4 which was broken into subbasins B-1 and B-2 for each of the receiving inlets. This portion of the right of way was conveyed from receiving inlets to a Stormtech System labeled R-4 on the Buffalo Run property. Similarly, runoff from the southern part of Gabriel Ave was accounted for in drainage area R-5 (sub-basins C-1 and C-2) and conveyed runoff to Stormtech System R-5 on the Buffalo Run property. Both of these streets were stubbed at the northern property line at essentially existing grade of the surrounding pasture. So, since the design of the streets extensions on the project site need to tie into the grade of these existing streets at the property line, the northern end of the proposed street extensions end up being very close to existing grade. Since the seasonal high groundwater (SHGW) table in this portion of the site is within 2’-3’ of existing grade, it is not feasible to design a stormwater system that captures runoff at the northern property line and conveys it to a facility that is 2’ above the SHGW table. Instead, a combination of approaches was used to account for the runoff from these streets. Rocky Mountain Flats – Stormwater Design Report Page 13 September 15, 2025 First, storm inlets were designed on both streets in locations to intercept as much runoff as possible while still being able to discharge to stormwater ponds that are above the SHGW table. These inlets ended up being located approximately 100’ south of the property line. The ponds (Pond 6 and 9) that these inlets drain to are not 2’ above the water table, but are above it so they will not be inundated with groundwater. Second, the two previously mentioned storm systems in Buffalo Run were analyzed to see if they could accommodate runoff from the northern 100’ of these streets from the project site. In order to accurately analyze these systems, the full drainage basins (B-1, B-2, C-1, and C-2) were analyzed in SSA with the additional 100’ of street right-of-way and the model was run to see if the existing inlets, pipes and Stormtech systems could accommodate runoff from the 10-year event. Since Buffalo Run was permitted under the previous city standards, the stormwater conveyance facilities were sized for the 25-year event, while the Stormtech retention facilities were sized for the 10-year 2-hr event. Since the new COB DSSP requires retention facilities to be sized for a 10-year storm duration and conveyance facilities to be sized for open flow during the 10-year storm instead of the 25-year storm, the existing facilities were determined to have sufficient capacity for the additional 100’ of street right-of-way when modeled under the new standards. The 10-year runoff volume for the Stormtech systems is outlined in the table in the “Minor Storm Event” section of this report and the pipe and inlet conveyance facilities are analyzed in the tables in Appendix C. These pipes, inlets, drainage basins, and Stormtech systems are labeled on the post- development drainage basin Map in Appendix A as well, for reference. Meah Lane The eastern portion of Meah Lane ties into the existing Meah Lane right-of-way at the intersection with S31st Ave in the SE corner of the property. In order to design drainage facilities for Meah Lane that were 2’ above the SHGW table, a high point had to be designed in Meah Lane immediately west of the intersection with 31st Ave. This results in a small portion of Meah Lane that drains off site to the east instead of on site to retention facilities. The southern part of this off-site area consists of Drainage Basin 10 and includes the western half of the S 31st right of way and the south half of the Meah Lane right-of-way. Runoff from this area will be captured in two LID boulevard swales in the right-of-way. These swales are sized to retain 100% of the 10-year minor storm event runoff volume. During the major storm event, runoff would overtop these swales and flow to retention pond #8 in the opens space to the SW. The northern part of this right of way connects to the existing curb on the north side of Meah Lane and continues east to North 30th Avenue. This small drainage basin is labeled “31st Ave” on the post development drainage basin map. The 10-year minor storm event for this drainage basin produces a peak runoff flow rate of 0.13 cfs and 38 cf of runoff. Since this is an insignificant amount of runoff, a drainage facility was not provided for this drainage basin. Instead, this runoff will flow to the existing storm system on North 30th Avenue. GROUNDWATER CONSIDERATIONS In accordance with the COB DSSP the proposed stormwater retention facilities were set so that the bottom of the systems are 2 feet above the estimated seasonal high groundwater elevation. The only situations where this was not feasible was for the retention ponds at Storm System 6 and Storm System 9. An explanation of why these systems could not maintain 2’ of separation above the seasonal high water table was provided in the “Edgerton and Gabriel Avenue” section of the report above. Appendix A Drainage Basin Maps XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPT ELEC T OHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHP16''W16''W8''W 8''W 8''W 8''W 8''W 8''W 8''SS8''W8''W 8''W 8''W 8''W8''W8''W8''W8''W8''SSXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXOOOOOOOOOO<><>SSGASGASGASGASGASXXXXXXXXXXXUGPUGPUGPUGPUGPUGPGASGASCOMMCOMMCOMMCOMMUGPUGPUGPXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX OHP OHP OHP OHP OHP OHP W VW V W V HYDW V W VW VW V W VW VHYDH YDHYD15''SS15''SS15''SS15''SS15''SS15''SSUGPUGPUGPUGP UGP UGP UGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGPUGP UGPUGPUGP UGP UGP UGP UGP UGP UGP UGP UGPUGPUGPSTSWR SWR SWR SWR SWR SWR SWR SWRSWRSWRSWRSWRSWRSWRSWRSWRSWR SWRSWRSWRSWRSWRSWRSWRSWR SWR CO 5010 5007 5008 5009 501 1 5010 5007 5007 5008 5009 5011 5012 5013 5014 5010 5008 5008 5 0 0 8 500 9 5011 5 0 1 2 50 1 3 5014 5010 5006 5 0 0 6 5 0 0 7 5008 50095011 5012 5012 5013 5013 DA PRE 1 Q100YR= 0.79 CFS V100YR= 1459 CF GABRIEL AVEMEAH LANEEDGERTON BLVDFOWLER LANES 31st AVEDA PRE 2 Q100YR= 0.45 CFS V100YR= 2778 CF DA PRE 3 Q100YR= 0.60 CFS V100YR= 3483 CF DA PRE 4 Q100YR= 0.19 CFS V100YR= 1168 CF 0 50'100' SCALE 1" = 50' N PRE DEVELOPMENT DRAINAGE AREA MAP BOZEMAN, MT ROCKY MOUNTAIN FLATS DATE: 5/28/2025 PROJECT NO: 749-01 BUFFALO RUN (EXISTING) ASSUMED TIME OF CONCENTRATION (TYP.) PREDEVELOPMENT SUBBASIN BOUNDARY 15S15S15S15S15S15S15S6W16W16W16W16W16W16W16W16W16W16W16W16W16W16W6W SS SS SS WS WS SSWS WS WS 6W15S15S15S15S15S15S15S15SE E E E E E E E E E E EE E E E E E E E G G G G BP BP BP BPE E NGBP NG UTILUTILUTIL NG NGUTILUTILUTIL BP BPBP BPBPBPBP BP BP BPBPBPBPUTILUTIL UTIL UTIL UTILUTILUTILUTIL W D D D D D D D D D D D D D 18SD18SD18SD18SD18SD18SD18SD18SD18SD18SD18SD18SDD D DD WSWSWSFIRE WSFIRE WS FIREFIREWSWSFIRE WSFIRE WSFIRE FIREFIRE FIRE WS 8W8W8W8W8W8W8W8W8W8W8W8W8W8W8WDYH DYHDYH DYH DYH 8W 8W 8W 8W 8WDYH 8W8W8W8W8W8W8W8W8W8W8W8W8W8W8W8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W8W8W8W8W8W8W8W8W8W8W8W8W8W8W8WDYHDYH 8W8W8W8W8W8W8W8W8W8W8W8W8W 8W 8W 8W S S 8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8S8SS S S S S S S SSSSSS SS8S8S8S8S8S8S8S8S8S8S8S8S8S8S8SSS8S8S8S8S8S8S8S8S8S8S8S 8S 8S 8S co co S 8''W16''W16''W8''W 8''W 8''W 8''W 8''W 8''W 8''SS8''W8''W 8''W 8''W 8''W8''W8''W8''W8''W8''SS<><>W VW VW V HYDW V W VW VW VW VW VHYDHY DHYD15''SS15''SS15''SS15''SS15''SS15''SSGASGASGASGASCO STSTSTSTCO CO ST DSDSDS DS DS DS DS DS DS DS DS DS DS DS DSDSDS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS ST ST ST ST ST ST ST ST ST ST STSTSTST STSTSTSTELECELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC 8''SS8''SS8''SS8''SS8''SS8''W8''W8''W8''W8''W8''W8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W8''W8''W8''W8''W16''W16''W16''W16''W8''SS8''SS8''SS8''SS8''SSW V W V W VW V W VW VW V W V SS SS W VHY DHYD HYDHY DW VW VW V SS SS ST ST STSTST S T ST ST ST STSTSTW V W V W V W V W VW V ST 15''SS15''SS15''SS15''SSWBO HYDGASGASGASGASGASGASOSW W V WBO WBO WBO WBO WBO WBO W VW V ELEC WBO WBO DA 2A DA 2C (8.50) (13.50) (13.15) DA B-1 DA B-2 DA C-1 DA C-2 DA 1BDA 1A DA 1C DA 1D DA 3A DA 3B DA 3C DA 2D DA10 DA 31ST AVE DA 2E DA 3D DA OFFSITE 1 DA OFFSITE 1 DA 9A DA 9B DA 9DDA 9CDA 8B DA 8A2 DA 7B DA 7A DA 6A DA 6B DA 5B DA 5A DA 4A DA 4B DA 6C DA 2B STORMTECH CHAMBER #2-3 MODEL: SC160LP (10-YR) VREQ.= 186 CF VPRO.= 579 CF BOTTOM OF STONE: 5009.00 GW: 5007.00 STORMTECH CHAMBER #2-1 MODEL: SC160LP (10-YR) VREQ.= 512 CF VPRO.=1,761 CF BOTTOM OF SYSTEM STONE: 5007.10 SHGW: 5004.80 STORMTECH CHAMBER #2-2 MODEL: SC160LP (10-YR) VREQ.= 777 CF VPRO.=1,544 CF BOTTOM OF SYSTEM STONE: 5006.10 SHGW: 5003.90 STORMTECH CHAMBER #1 MODEL: SC160LP (10-YR) VREQ.= 1,945 CF VPRO.=2,612 CF BOTTOM OF SYSTEM STONE: 5007.50 SHGW: 5005.50 OVERFLOW RETENTION POND #2-2 4:1 SIDE SLOPES (10-YR) VREQ.= NA VPRO.=3,577 CF TOP: 5006.50 BOTTOM: 5005.00 GW: 5004.90 STORMTECH CHAMBER #3 MODEL: SC160LP (10-YR) VREQ.= 2,087 CF VPRO.=3,044 CF BOTTOM OF STONE: 5009.30 GW: 5007.30 ST 5-3 (PC) ST 5-4 (PC) ST 1C-1 (PC) ST 1A-1 (ID) ST 1A-2 (DB) ST 1A-3 (ID) ST 1A-5 (ID) ST 1A-4 (DB) ST 1A-7 (DB)ST 1B-7 (ID) ST 1B-4 (DB) ST 1D-1 (PC) ST 1B-3 (ID) ST 1B-2 (DB) ST 1B-1 (ID) ST 5-2 (PC) ST 7-2 (PC) ST 2D-1 (PC) ST 2D-2 (PC)ST 2A-3 (DB) ST 2A-4 (DB) ST 2A-6 (DB)ST 2A-8 (PC) ST 2A-7 (ID) ST 2B-2 (PC) ST 2B-1 (PC) ST 7-3 (PC) ST 2A-9 (PC) ST 2C-1 (PC) ST 2C-2 (PC) ST 7-4 (PC) ST 3C-1 (PC) ST 3C-2 (PC)ST 3A-5 (DB) ST 3A-6 (ID) ST 3A-8 (ID) ST 3A-7 (DB) ST 3A-4 (ID) ST 3A-2 (DB) ST 3A-1 (ID) ST 8-3 (PC) ST 8-2 (PC) ST 8-1 (PC) ST 3B-1 (ID) ST 3B-2 (DB) ST 3B-3 (ID) ST 3B-4 (DB) ST 3B-5 (ID) ST 3B-6 (DB) ST 3B-9 (ID) ST 3D-2 (PC) ST 9-2 (PC) ST 6-2 (PC) ST 6-3 (PC) ST 4-2 (PC) ST 4-1 (PC) ST 3D-1 (PC) ST 6-1 (PC) ST 1D-2 (PC) ST 5-1 (PC) ST 1C-2 (PC) ST 7-1 (PC) STORMTECH CHAMBER #7 MODEL: SC160LP (10-YR) VREQ.= 563 CF VPRO.=1,474 CF BOTTOM OF STONE: 5007.10 GW: 5005.00 STORMTECH CHAMBER #8 MODEL: SC160LP (10-YR) VREQ.= 109 CF VPRO.=706 CF BOTTOM OF STONE: 5009.70 GW: 5007.65 STORMTECH CHAMBER #5 MODEL: SC160LP (10-YR) VREQ.= 368 CF VPRO.= 1,612 CF BOTTOM OF SYSTEM STONE: 5007.90 SHGW: 5005.90 STORM SYSTEM #10 (SWALES) 4:1 SIDE SLOPES (10-YR) VREQ.= 57 CF VPRO.= 64 CF STORM SYSTEM #6 (RETENTION POND) TOP DIMENSIONS: 230' x 13' 4:1 SIDE SLOPES (10-YR) VREQ.= 403 CF VPRO.=2,393 CF ELEVATIONS: 5005.40 (TOP) 5003.90 (BOTTOM) SHGW ELEV: 5003.50 12" CULVERT TO HYDRAULICALLY CONNECT PONDS STORM SYSTEM #9 (RETENTION POND) 4:1 SIDE SLOPES (10-YR) VREQ.= 787 CF VPRO.= 954 CF TOP: 5008.00 BOTTOM: 5006.80 GW: 5006.60 STORM SYSTEM #8 (RETENTION POND) 4:1 SIDE SLOPES (10-YR) VREQ.= 390 CF VPRO.= 1,566 CF TOP: 5013.15 BOTTOM: 5012.25 GW: 5010.10 OVERFLOW RETENTION POND #2-1 4:1 SIDE SLOPES (10-YR) VREQ.= NA VPRO.=1,053 CF TOP: 5006.50 BOTTOM: 5005.00 GW: 5004.90 DA 8A1 STORM SYSTEM #4 (LID POND) TOP DIMENSIONS: 53' x 18' 4:1 SIDE SLOPES (10-YR) VREQ.= 399 CF VPRO.=1,761 CF ELEVATIONS: 5007.20 (TOP) 5005.70 (BOTTOM) SHGW ELEV: 5003.50 DA FOWLER RUN-ON DA F-EAST Pipe 4-3 Pipe 4-2 Pipe 4-1 Pipe 1A-1 Pipe 1A-2 Pipe 1A-3 Pipe 1A-5 Pipe 1A-6 Pipe 1A-4 Pipe 1A-7 Pipe 1C-1 Pipe 5-1 Pipe 5-2 Pipe 1D-1 Pipe 1B-2 Pipe 1B-3 Pipe 1B-4 Pipe 1B-7 Pipe 1B-1 Pipe 6-2 Pipe 6-3 Pipe 2D-1 Pipe 7-2 Pipe 7-1 Pipe 2A-3 Pipe 2A-5 Pipe 2A-7 Pipe 2A-6 Pipe 2B-1 Pipe 2C-1 Pipe 3A-8 Pipe 3A-7 Pipe 3A-5 Pipe 3C-1 Pipe 3A-6 Pipe 3A-4 Pipe 3A-3 Pipe 3A-1 Pipe 8-1 Pipe 3B-1 Pipe 3B-2 Pipe 3B-3 Pipe 3B-5 Pipe 3B-6 Pipe 3B-8 Pipe 3B-4 Pipe 3D-1 Pipe 9-1 Pipe 9-2 ST 9-1 (PC) STORMTECH CHAMBER #R-5 (10-YR) VREQ.= 722 CF VPRO.=1,454 CF STORMTECH CHAMBER #R-4 (10-YR) VREQ.= 760 CF VPRO.=1,210 CF GABRIEL AVEMEAH LANEEDGERTON BLVDFOWLER LANEMEAH LANE S 31st AVE(12.25) DA B-1A DA B-2A DA C-1A DA C-2A Pipe 6-1 Pipe 1B-5ST 1A-6 (ID) ST 1A-8 (ID) Pipe 1A-8 Pipe 1A-9 ST 1A-9 (ID)ST 1B-6 (ID) ST 1B-5 (ID) Pipe 1B-6 ST 3B-8 (ID) ST 3A-9 (ID) Pipe 3A-9 Pipe 3A-10 ST 3A-10 Pipe 3B-9 ST 3B-7 (ID) Pipe 3B-7 Pipe 3A-2 ST 3A-3 (ID) ST 2A-5 (ID) Pipe 2A-4 Pipe 2A-2 ST 2A-2 (ID) Pipe 2A-1 ST 2A-1 (ID) 0 50'100' SCALE 1" = 50' N POST DEVELOPMENT DRAINAGE AREA MAP BOZEMAN, MT ROCKY MOUNTAIN FLATS DATE: 11/13/2025 PROJECT NO: 749-01 BUFFALO RUN (EXISTING) OVERFLOW AREA A OVERFLOW AREA B OVERFLOW AREA C OVERFLOW AREA E OVERFLOW AREA F OVERFLOW AREA G DA F WEST DRAINS TO INLETS F-01 AND F-02 AND CORRESPONDING PIPES F-WEST-LATERAL AND F-WEST-BYPASS IN FOWLER LANE (INSTALLED WITH BUFFALO RUN IMPROVEMENTS) PIPE R-4.1 PIPE B-1 LATERAL PIPE R-5.1 PIPE C-2 LATERAL INLET STB-1 INLET STR-4.1 INLET STR-5.1 INLET STC-2 DA F-WEST A DA F-WEST Appendix B Stormwater Storage Facility Calculations Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: Underground C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 1A 109 0.003 0.95 0.0024 DB - Pervious 1A 3204 0.074 0.22 0.0162 DB - Roof 1A 18992 0.436 0.95 0.4142 DB - R.o.w. 1A 0 0.000 0.74 0.0000 DB - Impervious 1B 139 0.003 0.95 0.0030 DB - Pervious 1B 2165 0.050 0.22 0.0109 DB - Roof 1B 16234 0.373 0.95 0.3541 DB - R.o.w. 1B 0 0.000 0.74 0.0000 DB - Impervious 1C 13238 0.304 0.95 0.2887 DB - Pervious 1C 1610 0.037 0.22 0.0081 DB - Roof 1C 0 0.000 0.95 0.0000 DB - R.o.w. 1C 0 0.000 0.74 0.0000 DB - Impervious 1D 13795 0.317 0.95 0.3009 DB - Pervious 1D 5509 0.126 0.22 0.0278 DB - Roof 1D 0 0.000 0.95 0.0000 DB - R.o.w. 1D 0 0.000 0.74 0.0000 Totals 74,995 1.72 1.4263 Weighted C:0.83 Required 10 yr Storm Volume (ft3)1,945 *generated from SSA Total Area (Acres) = 1.72 Weighted C = 0.83 Intensity (in/hr) = 0.098 Duration (hr) 24.00 Q (cfs) = 0.14 Req. 100-yr Runoff Volume (ft3)=12,077 DB 5 Runoff Volume (ft3)=2,703 Total Req. Runoff Volume (ft3)=14,780 System 1 Volume (ft3)2,612 System 5 Volume (ft3)1,611 Parking Lot Ponding Volume (ft3)10,800 15,023 Proposed Storage Volume Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations STORMTECH CHAMBER #1 Basis For Calculations Contributing Area & Runoff Coefficient Tabulation Storage Facility Information Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: Underground C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 2A 221 0.005 0.95 0.0048 DB - Pervious 2A 1,941 0.045 0.22 0.0098 DB - Roof 2A 19,773 0.454 0.95 0.4312 DB - R.o.w. 2A 0 0.000 0.74 0.0000 DB - Impervious 0 0.000 0.95 0.0000 DB - Pervious 0 0.000 0.22 0.0000 DB - Roof 0 0.000 0.95 0.0000 DB - R.o.w.0 0.000 0.74 0.0000 Totals 21,935 0.50 0.4458 Weighted C:0.89 Required 10 yr Storm Volume (ft3)512 *generated from SSA Total Area (Acres) = 0.50 Weighted C = 0.89 Intensity (in/hr) = 0.10 Duration (hr) 24.00 Q (cfs) = 0.04 Req. 100-yr Runoff Volume (ft3)=3,775 System 2-1 Volume (ft3)1,761 Additional Runoff to Drain to Facility 2-2 (ft3)2,014 Generated Runoff Volume - 100 year 24 hr Proposed 100 year Storage Volume Storage Facility Calculations STORMTECH CHAMBER #2-1 Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: Underground C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 2B 14284 0.328 0.95 0.3115 DB - Pervious 2B 1428 0.033 0.22 0.0072 DB - Roof 2B 0 0.000 0.95 0.0000 DB - R.o.w. 2B 0 0.000 0.74 0.0000 DB - Impervious 2C 14935 0.343 0.95 0.3257 DB - Pervious 2C 4989 0.115 0.22 0.0252 DB - Roof 2C 0 0.000 0.95 0.0000 DB - R.o.w. 2C 0 0.000 0.74 0.0000 Totals 35,636 0.818 0.6696 Weighted C:0.82 Required 10 yr Storm Volume (ft3)777 *generated from SSA Total Area (Acres) = 0.82 Weighted C = 0.82 Intensity (in/hr) = 0.10 Duration (hr) 24.00 Q (cfs) = 0.07 Req. 100-yr Runoff Volume (ft3)=5,670 System 2-1 Overflow Volume (ft3) =2,014 System 2-3 Overflow Volume (ft3) =436 System 7 Overflow Volume (ft3) =2,696 Total Req. Runoff Volume (ft3)10,816 System 2-2 Volume (ft3)1,544 Parking Lot Ponding Volume (ft3)4671 Total System Volume (ft3)6,215 Additional Runoff to Drain to Facility 2E (ft3) 4,601 Generated Runoff Volume - 100 year 24 hr Proposed Storage Volume Storage Facility Calculations STORMTECH CHAMBER #2-2 Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: Underground C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 2D 6385 0.147 0.95 0.1392 DB - Pervious 2D 4372 0.100 0.22 0.0221 DB - Roof 2D 0 0.000 0.95 0.0000 DB - R.o.w. 2D 0 0.000 0.74 0.0000 0 0.000 0.0000 0 0.000 0.0000 0 0.000 0.0000 0 0.000 0.0000 Totals 10,757 0.247 0.1613 Weighted C:0.65 Required 10 yr Storm Volume (ft3)186 *generated from SSA Total Area (Acres) = 0.25 Weighted C = 0.65 Intensity (in/hr) = 0.10 Duration (hr) 24.00 Q (cfs) = 0.02 Req. 100-yr Runoff Volume (ft3)=1,366 System 2-3 Volume (ft3)579 Parking Lot Ponding Volume (ft3)351 Total System Volume (ft3)930 Additional Runoff to Drain to Facility 2-2 (ft3) 436 Generated Runoff Volume - 100 year 24 hr Proposed Storage Volume Storage Facility Calculations STORMTECH CHAMBER #2-3 Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: Underground C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C) A (Ac) x C DB - Impervious 2E 275 0.006 0.95 0.0060 DB - Pervious 2E 11440 0.263 0.22 0.0578 DB - Roof 2E 0 0.000 0.95 0.0000 DB - R.o.w. 2E 0 0.000 0.74 0.0000 0 0.000 0.0000 0 0.000 0.0000 0 0.000 0.0000 0 0.000 0.0000 Totals 11,715 0.269 0.0638 Weighted C:0.24 Required 10 yr Storm Volume (ft3)239 *generated from SSA Total Area (Acres) = 0.27 Weighted C = 0.24 Intensity (in/hr) = 0.10 Duration (hr) 24.00 Q (cfs) = 0.01 Req. 100-yr Runoff Volume (ft3)=540 Overflow from System 2-2 (ft3) =4,601 Total Req. Runoff Volume (ft3)5,141 Pond 2-1 Volume (ft3)1,053 Pond 2-2 Volume (ft3)3,577 Total System Volume (ft3)4,630 Runoff onto adjacent Property (ft3)511 Pre-Dev Runoff at this location (PRE 3) (ft3)6,684 Generated Runoff Volume - 100 year 24 hr Proposed Storage Volume Storage Facility Calculations 2E (Overflow Pond) Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs) Facility Type: Underground C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 3A 138 0.003 0.95 0.0030 DB - Pervious 3A 2505 0.058 0.22 0.0127 DB - Roof 3A 18833 0.432 0.95 0.4107 DB - R.o.w. 3A 0 0.000 0.74 0.0000 DB - Impervious 3B 138 0.003 0.95 0.0030 DB - Pervious 3B 2256 0.052 0.22 0.0114 DB - Roof 3B 16454 0.378 0.95 0.3588 DB - R.o.w. 3B 0 0.000 0.74 0.0000 DB - Impervious 3C 13076 0.300 0.95 0.2852 DB - Pervious 3C 1981 0.045 0.22 0.0100 DB - Roof 3C 0 0.000 0.95 0.0000 DB - R.o.w. 3C 0 0.000 0.74 0.0000 DB - Impervious 3D 10557 0.242 0.95 0.2302 DB - Pervious 3D 3041 0.070 0.22 0.0154 DB - Roof 3D 0 0.000 0.95 0.0000 DB - R.o.w. 3D 0 0.000 0.74 0.0000 Totals 68,978 1.58 1.3404 Weighted C:0.85 Required 10 yr Storm Volume (ft3)2,087 *generated from SSA Total Area (Acres) = 1.58 Weighted C = 0.85 Intensity (in/hr) = 0.10 Duration (hr) 24.00 Q (cfs) = 0.13 Req. 100-yr Runoff Volume (ft3)=11,349 System 8B Overflow Volume (ft3) =86 Total Req. Runoff Volume (ft3)=11,435 System 3 Volume (ft3)3,044 Parking Lot Ponding Volume (ft3)8410 Total Storage Volume (ft3)11,454 Proposed Storage Volume Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations STORMTECH CHAMBER #3 Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: LID Pond C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 4A 230 0.005 0.95 0.0050 DB - Pervious 4A 4564 0.105 0.22 0.0231 DB - Roof 4A 0 0.000 0.95 0.0000 DB - R.o.w. 4A 16819 0.386 0.66 0.2548 Totals 21,613 0.50 0.2829 Weighted C:0.57 Required 10 yr Storm Volume (ft3)399 *generated from SSA Total Area (Acres) = 0.50 Weighted C = 0.57 Intensity (in/hr) = 0.10 Duration (hr) 24.00 Q (cfs) = 0.03 Req. 100-yr Runoff Volume (ft3)=2,395 Proposed LID Pond Volume (ft3)437 Excess Runoff draining to 18" trunk main Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations STORM SYSTEM #4 (LID POND) Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: LID Pond C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 4B 0 0.000 0.95 0.0000 DB - Pervious 4B 0 0.000 0.22 0.0000 DB - Roof 4B 0 0.000 0.95 0.0000 DB - R.o.w. 4B 4055 0.093 0.74 0.0689 Totals 4,055 0.09 0.0689 Weighted C:0.74 Required 10 yr Storm Volume (ft3)80 *generated from SSA Total Area (Acres) = 0.09 Weighted C = 0.74 Intensity (in/hr) = 0.10 Duration (hr) 24.00 Q (cfs) = 0.01 Req. 100-yr Runoff Volume (ft3)=583 DA 4B is draining to ex. Hydrodynamic Separator for WQV Treatment Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations DA 4B (Trunk Main) Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: Underground C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 5A 0 0.000 0.95 0.0000 DB - Pervious 5A 0 0.000 0.22 0.0000 DB - Roof 5A 0 0.000 0.95 0.0000 DB - R.o.w. 5A 10655 0.245 0.74 0.1810 DB - Impervious 5B 0 0.000 0.95 0.0000 DB - Pervious 5B 0 0.000 0.22 0.0000 DB - Roof 5B 0 0.000 0.95 0.0000 DB - R.o.w. 5B 8138 0.187 0.74 0.1382 Totals 18,792 0.43 0.3192 Weighted C:0.74 Required 10 yr Storm Volume (ft3)368 *generated from SSA Total Area (Acres) = 0.43 Weighted C = 0.74 Intensity (in/hr) = 0.10 Duration (hr) 24.00 Q (cfs) = 0.03 Req. 100-yr Runoff Volume (ft3)=2,703 Proposed Retention Pond Volume (ft3)1611 Additional Runoff to Drain to Facility 1 (ft3)1,092 See Stormtech Chamber #1 Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations STORMTECH CHAMBER #5 Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: Pond C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 6A 454 0.010 0.95 0.0099 DB - Pervious 6A 4662 0.107 0.22 0.0235 DB - Roof 6A 0 0.000 0.95 0.0000 DB - R.o.w. 6A 6754 0.155 0.74 0.1147 DB - Impervious 6B 181 0.004 0.95 0.0039 DB - Pervious 6B 3673 0.084 0.22 0.0186 DB - Roof 6B 0 0.000 0.95 0.0000 DB - R.o.w. 6B 7321 0.168 0.74 0.1244 DB - Impervious 6C 0 0.000 0.95 0.0000 DB - Pervious 6C 11385 0.261 0.22 0.0575 DB - Roof 6C 0 0.000 0.95 0.0000 DB - R.o.w. 6C 0 0.000 0.74 0.0000 DB - Gravel 6C 2644 0.061 0.70 0.0425 Totals 37,074 0.85 0.3950 Weighted C:0.46 Required 10 yr Storm Volume (ft3)403 *generated from SSA Total Area (Acres) = 0.85 Weighted C = 0.46 Intensity (in/hr) = 0.10 Duration (hr) 24.00 Q (cfs) = 0.04 Req. 100-yr Runoff Volume (ft3)=3,345 Proposed Retention Pond Volume (ft3)2,393 Additional Runoff to pond in low points on property line (ft3)952 Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations STORM SYSTEM #6 (RET. POND) Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: Underground C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 7A 0 0.000 0.95 0.0000 DB - Pervious 7A 0 0.000 0.22 0.0000 DB - Roof 7A 0 0.000 0.95 0.0000 DB - R.o.w. 7A 13777 0.316 0.74 0.2340 DB - Impervious 7B 501 0.012 0.95 0.0109 DB - Pervious 7B 3806 0.087 0.22 0.0192 DB - Roof 7B 0 0.000 0.95 0.0000 DB - R.o.w. 7B 13431 0.308 0.74 0.2282 Totals 31,516 0.72 0.4924 Weighted C:0.68 Required 10 yr Storm Volume (ft3)536 *generated from SSA Total Area (Acres) = 0.72 Weighted C = 0.68 Intensity (in/hr) = 0.10 Duration (hr) 24.00 Q (cfs) = 0.05 Req. 100-yr Runoff Volume (ft3)=4,169 System 7 Volume (ft3)1,473 Additional Runoff to Drain to Facility 2-2 (ft3)2,696 Proposed Storage Volume Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations STORMTECH CHAMBER #7 Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: Pond C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 8A 0 0.000 0.95 0.0000 DB - Pervious 8A 14187 0.326 0.22 0.0717 DB - Roof 8A 0 0.000 0.95 0.0000 DB - R.o.w. 8A 9329 0.214 0.74 0.1585 Totals 23,516 0.54 0.2301 Weighted C:0.43 Required 10 yr Storm Volume (ft3)390 *generated from SSA Total Area (Acres) = 0.54 Weighted C = 0.43 Intensity (in/hr) = 0.10 Duration (hr) 24.00 Q (cfs) = 0.02 Req. 100-yr Runoff Volume (ft3)=1,949 System 10 Overflow Volume (ft3) =348 Total Runoff Volume (ft3)2,297 Pond 8 Volume (ft3)1,566 Additional Open Space Ponding Volume (ft3)750 Total System Volume (ft3)2,316 Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations STORM SYSTEM #8 (RET. POND) Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: Underground C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 8B 0 0.000 0.95 0.0000 DB - Pervious 8B 0 0.000 0.22 0.0000 DB - Roof 8B 0 0.000 0.95 0.0000 DB - R.o.w. 8B 5504 0.126 0.74 0.0935 Totals 5,504 0.13 0.0935 Weighted C:0.74 Required 10 yr Storm Volume (ft3)109 *generated from SSA Total Area (Acres) = 0.13 Weighted C = 0.74 Intensity (in/hr) = 0.10 Duration (hr) 24.00 Q (cfs) = 0.01 Req. 100-yr Runoff Volume (ft3)=792 System 8B Volume (ft3)706 Additional Runoff to Drain to Facility 3 (ft3)86 Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations STORMTECH CHAMBER #8 Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: Pond C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 9A 76 0.002 0.95 0.0017 DB - Pervious 9A 2150 0.049 0.22 0.0109 DB - Roof 9A 0 0.000 0.95 0.0000 DB - R.o.w. 9A 4719 0.108 0.74 0.0802 DB - Impervious 9B 0 0.000 0.95 0.0000 DB - Pervious 9B 0 0.000 0.22 0.0000 DB - Roof 9B 0 0.000 0.95 0.0000 DB - R.o.w. 9B 7090 0.163 0.74 0.1204 DB - Impervious 9C 0 0.000 0.95 0.0000 DB - Pervious 9C 0 0.000 0.22 0.0000 DB - Roof 9C 0 0.000 0.95 0.0000 DB - R.o.w. 9C 2705 0.062 0.74 0.0460 DB - Impervious 9D 0 0.000 0.95 0.0000 DB - Pervious 9D 33828 0.777 0.22 0.1708 DB - Roof 9D 0 0.000 0.95 0.0000 DB - R.o.w. 9D 0 0.000 0.74 0.0000 Totals 50,568 1.16 0.4299 Weighted C:0.37 Required 10 yr Storm Volume (ft3)787 *generated from SSA Total Area (Acres) = 1.16 Weighted C = 0.37 Intensity (in/hr) = 0.098 Duration (hr) 24.00 Q (cfs) = 0.04 Req. 100-yr Runoff Volume (ft3)=3,640 Proposed Retention Pond 9 Volume (ft3)1053 Park Ponding Volume (ft3)572 Total System Volume (ft3)1,625 Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations STORM SYSTEM #9 (RET. POND) Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: Swale C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 10A 0 0.000 0.95 0.0000 DB - Pervious 10A 0 0.000 0.22 0.0000 DB - Roof 10A 0 0.000 0.95 0.0000 DB - R.o.w. 10A 2866 0.066 0.74 0.0487 DB - Impervious 10B 0 0.000 0.95 0.0000 DB - Pervious 10B 0 0.000 0.22 0.0000 DB - Roof 10B 0 0.000 0.95 0.0000 DB - R.o.w. 10B 0 0.000 0.74 0.0000 DB - Impervious 0 0.000 0.95 0.0000 DB - Pervious 0 0.000 0.22 0.0000 DB - Roof 0 0.000 0.95 0.0000 DB - R.o.w.0 0.000 0.74 0.0000 DB - Impervious 0 0.000 0.95 0.0000 DB - Pervious 0 0.000 0.22 0.0000 DB - Roof 0 0.000 0.95 0.0000 DB - R.o.w.0 0.000 0.74 0.0000 Totals 2,866 0.07 0.0487 Weighted C:0.74 Required 10 yr Storm Volume (ft3)57 *generated from SSA Total Area (Acres) = 0.07 Weighted C = 0.74 Intensity (in/hr) = 0.098 Duration (hr) 24.00 Q (cfs) = 0.00 Req. 100-yr Runoff Volume (ft3)=412 Swale 10 Volumes (ft3)64 Additional Runoff to Drain to Facility 8 (ft3)348 Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations STORM SYSTEM #10 (SWALE) Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: N/A Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: N/A C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious F-West A 0 0.000 0.95 0.0000 DB - Pervious F-West A 0 0.000 0.22 0.0000 DB - Roof F-West A 0 0.000 0.95 0.0000 DB - R.o.w. F-West A 6317 0.145 0.95 0.1378 DB - R.o.w. F-West 11761 0.270 0.9 0.2430 * Per Buffalo Run Report Totals 18,078 0.42 0.3808 Weighted C:0.92 Required 10 yr Storm Volume (ft3)446 *generated from SSA Total Area (Acres) = 0.42 Weighted C = 0.92 Intensity (in/hr) = 0.098 Duration (hr) 24.00 Q (cfs) = 0.04 Req. 100-yr Runoff Volume (ft3)=3,224 Draining to ex. Hydrodynamic Separator for WQV Treatment Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations F-West (Trunk Main Buffalo Run) Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: LID Pond C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious F-East 0 0.000 0.95 0.0000 DB - Pervious F-East 0 0.000 0.22 0.0000 DB - Roof F-East 0 0.000 0.95 0.0000 DB - R.o.w. F-East 1372 0.031 0.95 0.0299 Totals 1,372 0.03 0.0299 Weighted C:0.95 Required 10 yr Storm Volume (ft3)24 *generated from SSA Total Area (Acres) = 0.03 Weighted C = 0.95 Intensity (in/hr) = 0.098 Duration (hr) 24.00 Q (cfs) = 0.00 Req. 100-yr Runoff Volume (ft3)=253 Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations F-East (LID Pond Buffalo Run) Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: Underground C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - R.o.w. B-1 15681 0.360 0.75 0.2700 * Per Buffalo Run Report DB - Impervious B-1A 199 0.005 0.95 0.0043 DB - Pervious B-1A 799 0.018 0.22 0.0040 DB - Roof B-1A 0 0.000 0.95 0.0000 DB - Gravel B-1A 190 0.004 0.70 0.0031 DB - R.o.w. B-1A 2400 0.055 0.74 0.0408 DB - R.o.w. B-2 14810 0.340 0.75 0.2550 * Per Buffalo Run Report DB - Impervious B-2A 76 0.002 0.95 0.0017 DB - Pervious B-2A 961 0.022 0.22 0.0049 DB - Roof B-2A 0 0.000 0.95 0.0000 DB - Gravel B-2A 0 0.000 0.7 0.0000 DB - R.o.w. B-2A 2400 0.055 0.74 0.0408 Totals 37,517 0.86 0.6245 Weighted C:0.73 Required 10 yr Storm Volume (ft3)760 *generated from SSA Total Area (Acres) = 0.86 Weighted C = 0.73 Intensity (in/hr) = 0.098 Duration (hr) 24.00 Q (cfs) = 0.06 Req. 100-yr Runoff Volume (ft3)=5,288 Provided Retention Pond Volume (ft3)1,210 * Per Buffalo Run Report Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations R-4 (Buffalo Run) Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: Retention Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: Underground C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - R.o.w. C-1 22215 0.510 0.95 0.4845 * Per Buffalo Run Report DB - Impervious C-1A 176 0.004 0.95 0.0038 DB - Pervious C-1A 902 0.021 0.22 0.0046 DB - Roof C-1A 0 0.000 0.95 0.0000 DB - Gravel C-1A 144 0.003 0.70 0.0023 DB - R.o.w. C-1A 3095 0.071 0.74 0.0526 DB - R.o.w. C-2 11761 0.270 0.95 0.2565 * Per Buffalo Run Report DB - Impervious C-2A 0 0.000 0.95 0.0000 DB - Pervious C-2A 0 0.000 0.22 0.0000 DB - Roof C-2A 0 0.000 0.95 0.0000 DB - R.o.w. C-2A 390 0.009 0.74 0.0066 Totals 38,684 0.89 0.8109 Weighted C:0.91 Required 10 yr Storm Volume (ft3)722 *generated from SSA Total Area (Acres) = 0.89 Weighted C = 0.91 Intensity (in/hr) = 0.098 Duration (hr) 24.00 Q (cfs) = 0.08 Req. 100-yr Runoff Volume (ft3)=6,866 Provided Retention Pond Volume (ft3)1,454 * Per Buffalo Run Report Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations R-5 (Buffalo Run) Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: N/A Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: N/A C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C) A (Ac) x C DB - Impervious OFFSITE 1 0 0.000 0.95 0.0000 DB - Pervious OFFSITE 1 5181 0.119 0.22 0.0262 DB - Roof OFFSITE 1 0 0.000 0.95 0.0000 DB - R.o.w. OFFSITE 1 0 0.000 0.74 0.0000 DB - Gravel OFFSITE 1 2586 0.059 0.70 0.0415 Totals 7,767 0.18 0.0677 Weighted C:0.38 Required 10 yr Storm Volume (ft3)117 *generated from SSA Total Area (Acres) = 0.18 Weighted C = 0.38 Intensity (in/hr) = 0.098 Duration (hr) 24.00 Q (cfs) = 0.01 Req. 100-yr Runoff Volume (ft3)=573 Proposed Retention Volume (ft3)0 Runoff to pond in low points on property line (ft3)573 Pre-Dev Runoff at this location (PRE 2) (ft3)6,684 Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations Offsite 1 Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Design Rainfall Frequency (year): 100 Storage Method: N/A Rational Method Peak Runoff Equation: Q = CIA Discharge Method: N/A Q = Peak Runoff Rate (cfs)Facility Type: N/A C = Runoff Coefficient Facility Make/Model: N/A I = Rainfall Intensity (in/hr): 0.098 A = Drainage Basin (acres) Land Use Drainage Basin Number Contributing Area (sf) Contributing Area (Ac) Runoff Coe. (C)A (Ac) x C DB - Impervious 31st Ave 0 0.000 0.95 0.0000 DB - Pervious 31st Ave 0 0.000 0.22 0.0000 DB - Roof 31st Ave 0 0.000 0.95 0.0000 DB - R.o.w. 31st Ave 2021 0.046 0.74 0.0343 DB - Gravel 31st Ave 0 0.000 0.70 0.0000 Totals 2,021 0.05 0.0343 Weighted C:0.74 Required 10 yr Storm Volume (ft3)38 *generated from SSA Total Area (Acres) = 0.05 Weighted C = 0.74 Intensity (in/hr) = 0.098 Duration (hr) 24.00 Q (cfs) = 0.00 Req. Runoff Volume (ft3)=291 Proposed Retention Pond Volume (ft3)0 Runoff to flow down Meah Lane Curb (ft3)291 Generated Runoff Volume - 100 year 24 hr Storage Facility Calculations Offsite (31st Ave) Basis For Calculations Storage Facility Information Contributing Area & Runoff Coefficient Tabulation Appendix C SSA Model Results Conveyance Facility Summary Table - Pipes Peak Flow (cfs) Time of Peak Flow (hr:mm) Max Flow Velocity (ft/sec) Max Flow Depth (ft) Max Flow / Design Flow Ratio Max Flow Depth / Total Flow Depth Ratio Total Time Surcharged (min) Peak Flow (cfs) Time of Peak Flow (hr:mm) Max Flow Velocity (ft/sec) Max Flow Depth (ft) Max Flow / Design Flow Ratio Max Flow Depth / Total Flow Depth Ratio Total Time Surcharged (min) B-1 Lateral 0.50 12 0.013 2.53 1.18 0 00:05 3.17 0.48 0.47 0.48 0.00 1.65 0 00:05 3.44 0.59 0.65 0.59 0.00 C-2 Lateral 0.30 12 0.012 2.10 0.82 0 00:05 3.05 0.43 0.39 0.43 0.00 1.17 0 00:05 3.40 0.53 0.56 0.53 0.00 F-West-Bypass 0.50 12 0.012 2.72 0.16 0 00:05 1.90 0.16 0.06 0.16 0.00 0.52 0 00:05 2.67 0.30 0.19 0.30 0.00 F-West-Lateral 0.49 15 0.012 4.89 1.31 0 00:05 4.53 0.44 0.27 0.35 0.00 1.79 0 00:05 5.04 0.52 0.37 0.42 0.00 PIPE 1A-5 0.62 12 0.012 3.03 1.66 0 00:05 3.97 0.53 0.55 0.53 0.00 2.62 0 00:05 4.38 0.71 0.86 0.72 0.00 PIPE 1B-3 0.58 12 0.012 2.94 1.43 0 00:05 3.74 0.49 0.49 0.49 0.00 2.26 0 00:05 4.15 0.66 0.77 0.66 0.00 PIPE 1C-1 0.84 12 0.012 3.54 2.15 0 00:05 4.73 0.56 0.61 0.56 0.00 3.38 0 00:05 5.13 0.78 0.96 0.78 0.00 PIPE 1D-1 1.19 12 0.012 4.22 1.97 0 00:05 5.28 0.48 0.47 0.48 0.00 3.11 0 00:05 5.87 0.64 0.74 0.64 0.00 PIPE 2A-4 0.64 12 0.012 3.08 1.70 0 00:05 4.04 0.53 0.55 0.53 0.00 2.68 0 00:05 4.45 0.72 0.87 0.72 0.00 PIPE 2B-1 0.46 10 0.012 1.61 1.23 0 00:05 3.26 0.54 0.76 0.65 0.00 1.74 0 00:04 3.47 0.83 1.08 1.00 1.00 PIPE 2C-1 0.48 10 0.012 1.64 1.36 0 00:05 3.38 0.58 0.83 0.69 0.00 1.78 0 00:04 3.54 0.83 1.08 1.00 2.00 PIPE 2D-1 0.69 10 0.012 1.98 0.62 0 00:05 3.21 0.32 0.31 0.38 0.00 0.97 0 00:05 3.62 0.41 0.49 0.50 0.00 PIPE 3A-5 0.63 12 0.012 3.06 1.63 0 00:05 3.97 0.52 0.53 0.52 0.00 2.56 0 00:05 4.39 0.70 0.84 0.70 0.00 PIPE 3B-4 0.71 12 0.012 3.25 1.43 0 00:05 4.02 0.46 0.44 0.46 0.00 2.25 0 00:05 4.48 0.61 0.69 0.61 0.00 PIPE 3C-1 1.04 12 0.012 3.95 1.78 0 00:05 4.90 0.47 0.45 0.47 0.00 2.81 0 00:05 5.45 0.62 0.71 0.62 0.00 PIPE 3D-1 1.00 12 0.012 3.86 1.56 0 00:05 4.66 0.44 0.40 0.44 0.00 2.46 0 00:05 5.21 0.58 0.64 0.58 0.00 PIPE 4-1 1.65 18 0.012 14.60 1.05 0 00:05 4.83 0.27 0.07 0.18 0.00 1.67 0 00:05 5.49 0.34 0.11 0.23 0.00 PIPE 4-2 1.60 18 0.012 14.39 1.05 0 00:05 7.17 0.27 0.07 0.18 0.00 1.67 0 00:05 8.05 0.34 0.12 0.23 0.00 PIPE 4-3 1.57 18 0.012 14.27 0.84 0 00:05 4.43 0.25 0.06 0.16 0.00 1.33 0 00:05 5.07 0.31 0.09 0.21 0.00 PIPE 5-1 0.45 12 0.013 2.40 0.70 0 00:05 3.17 0.37 0.29 0.37 0.00 1.09 0 00:05 3.40 0.47 0.45 0.47 0.00 PIPE 5-2 0.52 15 0.013 4.65 1.19 0 00:05 3.24 0.43 0.26 0.34 0.00 1.88 0 00:05 3.66 0.55 0.40 0.44 0.00 PIPE 6-1 0.48 12 0.013 2.48 0.48 0 00:05 3.23 0.30 0.19 0.30 0.00 0.75 0 00:05 3.55 0.38 0.30 0.38 0.00 PIPE 6-2 0.50 15 0.011 5.41 0.94 0 00:05 3.34 0.35 0.17 0.28 0.00 1.49 0 00:05 3.79 0.45 0.27 0.36 0.00 PIPE 6-3 0.52 15 0.013 4.65 0.93 0 00:05 3.01 0.38 0.20 0.30 0.00 1.45 0 00:05 3.41 0.48 0.31 0.38 0.00 PIPE 7-1 0.61 12 0.013 2.77 0.90 0 00:05 3.47 0.39 0.32 0.39 0.00 1.41 0 00:05 3.85 0.50 0.51 0.50 0.00 PIPE 7-2 0.54 15 0.011 5.62 1.81 0 00:05 4.66 0.49 0.32 0.39 0.00 2.88 0 00:05 5.15 0.63 0.51 0.50 0.00 PIPE 8-1 0.51 12 0.011 3.00 0.35 0 00:05 4.35 0.23 0.12 0.23 0.00 0.55 0 00:05 4.81 0.29 0.18 0.29 0.00 PIPE 9-1 0.52 12 0.013 2.56 0.35 0 00:05 3.07 0.25 0.14 0.25 0.00 0.55 0 00:05 3.40 0.32 0.22 0.32 0.00 PIPE 9-2 0.52 15 0.011 5.53 0.79 0 00:05 3.25 0.32 0.14 0.25 0.00 1.25 0 00:05 3.69 0.40 0.23 0.32 0.00 R-4.1 0.52 12 0.012 2.79 2.30 0 00:05 3.98 0.69 0.82 0.69 0.00 3.02 0 00:05 4.20 1.00 1.08 1.00 1.00 R-5.1 0.32 12 0.012 2.19 2.35 0 00:05 3.27 0.91 1.07 0.91 0.00 2.37 0 00:03 3.32 1.00 1.08 1.00 3.00 Pipe Name 10-Year Storm Event 100-Year 24-Hr Storm Event Design Flow Capacity (cfs) Manning's Roughness Pipe Dia. (in) Average Slope (%) Conveyance Facility Summary Table - Structures Peak Flow (cfs) Peak Flow Intercepted by Inlet (cfs) Peak Flow Bypassing Inlet (cfs) Allowable Spread (ft) Max Gutter Spread during Peak Flow (ft) Max Gutter Water Depth during Peak Flow (ft) Peak Flow (cfs) Peak Flow Intercepted by Inlet (cfs) Peak Flow Bypassing Inlet (cfs) Max Gutter Spread during Peak Flow (ft) Max Gutter Water Depth during Peak Flow (ft) Inlet-F-01 0.16 0.16 0.00 9.50 1.66 0.10 0.52 0.52 0.00 3.68 0.16 Inlet-F-02 1.47 1.44 0.03 9.50 6.73 0.22 2.31 1.80 0.51 8.29 0.25 ST 1A-5 1.68 N/A N/A 9.50 8.29 0.27 2.64 N/A N/A 11.05 0.33 ST 1B-3 1.45 N/A N/A 9.50 7.55 0.26 2.28 N/A N/A 10.06 0.31 ST 1C-1 0.88 N/A N/A 9.50 1.43 0.13 1.38 N/A N/A 3.65 0.17 ST 1D-1 0.97 N/A N/A 9.50 1.86 0.14 1.52 N/A N/A 4.24 0.18 ST 2A-4 1.72 N/A N/A 9.50 9.33 0.29 2.70 N/A N/A 13.01 0.37 ST 2B-1 1.23 N/A N/A 9.50 3.03 0.16 1.93 N/A N/A 5.83 0.21 ST 2C-1 1.36 N/A N/A 9.50 3.61 0.17 2.15 N/A N/A 6.61 0.23 ST 2D-1 0.62 N/A N/A 9.50 0.14 0.10 0.98 N/A N/A 1.91 0.14 ST 3A-5 1.64 N/A N/A 9.50 8.17 0.27 2.58 N/A N/A 10.90 0.32 ST 3B-4 1.44 N/A N/A 9.50 7.53 0.26 2.27 N/A N/A 10.03 0.31 ST 3C-1 0.57 N/A N/A 9.50 0.00 0.10 0.90 N/A N/A 1.55 0.13 ST 3D-1 0.48 N/A N/A 9.50 0.00 0.09 0.76 N/A N/A 0.87 0.12 ST 4-2 0.27 N/A N/A 9.50 0.00 0.06 0.42 N/A N/A 0.00 0.08 ST 5-1 0.70 N/A N/A 9.50 2.76 0.11 1.10 N/A N/A 4.69 0.15 ST 5-2 0.54 N/A N/A 9.50 1.86 0.09 0.84 N/A N/A 3.47 0.12 ST 6-1 0.56 0.56 0.00 9.50 4.12 0.12 0.89 0.80 0.09 5.14 0.14 ST 6-2 0.57 0.57 0.00 9.50 4.15 0.12 0.89 0.80 0.10 5.15 0.14 ST 7-1 0.90 N/A N/A 9.50 3.77 0.13 1.42 N/A N/A 6.05 0.17 ST 7-2 1.01 N/A N/A 9.50 4.25 0.14 1.59 N/A N/A 6.70 0.19 ST 8-1 0.36 N/A N/A 9.50 0.00 0.07 0.57 N/A N/A 0.00 0.09 ST 9-1 0.36 0.36 0.00 9.50 3.79 0.12 0.56 0.56 0.00 4.74 0.13 ST 9-2 0.47 0.47 0.00 9.50 4.34 0.13 0.73 0.73 0.00 5.39 0.15 ST B-1 1.29 1.29 0.00 9.50 6.30 0.21 2.04 1.67 0.37 7.90 0.24 ST C-2 0.83 0.83 0.00 9.50 4.96 0.18 1.30 1.28 0.02 6.31 0.21 ST R-4.1 1.20 1.20 0.00 9.50 6.10 0.21 1.90 1.63 0.26 7.65 0.24 ST R-5.1 1.71 1.46 0.25 9.50 7.25 0.23 2.70 1.84 0.86 8.93 0.26 100-year 24-hr Storm Event10-year Storm Event Inlet Name Subbasin Summary Table Peak Runoff (cfs) Rainfall Intensity (in/hr Peak Runoff (cfs) Rainfall Intensity (in/hr 1A 0.51 0.85 0 00:05:00 1.68 3.87 2.64 6.09 1B 0.43 0.87 0 00:05:00 1.45 3.87 2.28 6.09 1C 0.34 0.87 0 00:09:07 0.88 2.95 1.38 4.64 1D 0.44 0.74 0 00:09:07 0.97 2.95 1.52 4.64 2A 0.50 0.88 0 00:05:00 1.72 3.87 2.70 6.09 2B 0.36 0.88 0 00:05:00 1.23 3.87 1.94 6.09 2C 0.46 0.77 0 00:05:00 1.37 3.87 2.15 6.09 2D 0.25 0.65 0 00:05:00 0.62 3.87 0.98 6.09 2E 0.29 0.72 0 00:05:00 0.80 3.87 1.25 6.09 31stAve 0.05 0.72 0 00:05:00 0.13 3.87 0.20 6.09 3A 0.49 0.86 0 00:05:00 1.64 3.87 2.58 6.09 3B 0.43 0.86 0 00:05:00 1.44 3.87 2.27 6.09 3C 0.35 0.85 0 00:18:28 0.57 1.95 0.90 3.07 3D 0.31 0.79 0 00:18:19 0.49 1.97 0.76 3.09 4A 0.50 0.57 0 00:07:10 0.93 3.29 1.46 5.17 4B 0.09 0.74 0 00:05:00 0.27 3.87 0.42 6.09 5A 0.25 0.74 0 00:05:00 0.70 3.87 1.10 6.09 5B 0.19 0.74 0 00:05:00 0.54 3.87 0.84 6.09 6A 0.27 0.54 0 00:05:00 0.57 3.87 0.89 6.09 6B 0.26 0.57 0 00:05:00 0.57 3.87 0.89 6.09 6C 0.32 0.31 0 00:05:00 0.39 3.87 0.61 6.09 7A 0.32 0.74 0 00:05:00 0.91 3.87 1.42 6.09 7B 0.41 0.64 0 00:05:00 1.01 3.87 1.59 6.09 8A1 0.21 0.74 0 00:05:00 0.61 3.87 0.96 6.09 8A2 0.33 0.22 0 01:11:55 0.05 0.67 0.07 1.03 8B 0.13 0.74 0 00:05:00 0.36 3.87 0.57 6.09 9A 0.16 0.58 0 00:05:00 0.36 3.87 0.56 6.09 9B 0.16 0.74 0 00:05:00 0.47 3.87 0.74 6.09 9C 0.06 0.74 0 00:05:00 0.18 3.87 0.28 6.09 9D 0.78 0.22 0 01:02:42 0.13 0.76 0.20 1.19 10A 0.07 0.74 0 00:05:00 0.19 3.87 0.30 6.09 B-1 0.36 0.75 0 00:05:00 1.05 3.87 1.64 6.09 B-1A 0.08 0.64 0 00:05:00 0.20 3.87 0.32 6.09 B-2 0.34 0.75 0 00:05:00 0.98 3.87 1.54 6.09 B-2A 0.08 0.60 0 00:05:00 0.18 3.87 0.29 6.09 C-1 0.51 0.75 0 00:05:00 1.47 3.87 2.31 6.09 C-1A 0.10 0.64 0 00:05:00 0.25 3.87 0.39 6.09 C-2 0.28 0.75 0 00:05:00 0.80 3.87 1.26 6.09 C-2A 0.01 0.74 0 00:05:00 0.03 3.87 0.04 6.09 F-East 0.03 0.66 0 00:05:00 0.08 3.87 0.13 6.09 FOWLER RUNON 0.23 0.95 0 00:05:00 0.85 3.87 1.33 6.09 F-W-Bypass 0.01 0.90 0 00:05:00 0.03 3.87 0.04 6.09 F-WEST 0.27 0.90 0 00:05:00 0.93 3.87 1.47 6.09 F-WEST-A 0.15 0.95 0 00:05:00 0.53 3.87 0.84 6.09 OFFSITE 1 0.18 0.41 0 00:08:55 0.22 2.98 0.34 4.69 10-year Storm Event 100-year 24-hr Storm Event Drainage Basin Name Area (acres) Weighted Runoff Coefficient Time of Concentration (hh:mm:ss) Appendix D Geotechnical Investigation January 30, 2025 Rocky Mountain Flats, LLLP Attn: Maddy Mason and Christian Pritchett E-mail: maddy@bluelinedevelopment.com christian@bluelinedevelopment.com RE: Geotechnical Investigation Report N½, S½, SW¼, SW¼ of Section 23 Gallatin County, Montana IMEG# 25000076.00 Dear Maddy and Christian, Per your request, IMEG has conducted a subsurface soils investigation for the above referenced property located in the Southwest Quarter of Section 23, Township 2 South, Range 5 East in Gallatin County, Montana. The scope of services was to conduct a subsurface soils investigation and provide a soils investigation report. The report documents the subsurface conditions, soil properties, and provides foundation design and general earthwork recommendations. This report also utilizes the subsurface soils observed during the installation of groundwater monitoring wells on the subject property in December of 2021. Proposed Construction It is understood that three multi-family residential structures are planned for construction. It is our understanding that the proposed structures will be constructed with a slab on grade with stem wall foundations and will utilize typical wood framing. The proposed structure’s are planned to be four to five stories in height with a total of 296-units. In determining the allowable bearing capacity and settlement estimates, it has been assumed that the foundation footings will not be subjected to unusual loading conditions such as eccentric loads. A footing is eccentrically loaded if the load transferred to the footing is not directed through the center of the footing. This creates a bending moment in the footing and results in a non-uniform load transfer to the underlying soil. If any of the foundation footings will be eccentrically loaded, please contact this office so we can appropriately revise our allowable bearing capacity and settlement estimates. Rocky Mountain Flats, LLLP – Geotechnical Investigation – Fowler Lane, Gallatin County Montana January 30, 2025 Page 2 of 15 Site Description The subject property has a total area of 10.0 acres and access is provided by Fowler Lane. The west half of the subject property has existing residential improvements consisting of a single-family residence, an additional dwelling unit in the southwest corner, a detached shop/garage in the northwest corner, and a septic drain field is located approximately 300 feet east of the residence. The east half of the property is currently undeveloped. No other significant topographical or geological features were observed in the direct vicinity of the desired building sites. Subsurface Soil and Conditions – Test Pits On December 21, 2021 a site visit was made to conduct a subsurface soils investigation and to install groundwater monitoring wells. The subsurface soils investigation consisted of examining seven exploratory test pit excavations. The exploratory test pits were excavated with a Hitachi tracked excavator provided by RLS Construction. The soil profiles revealed by the exploratory excavations were logged and visually classified according to ASTM D 2488, which utilizes the nomenclature of the Unified Soil Classification System (USCS). The relative density of each soil layer was estimated based on probing of the excavation sidewalls with a rock hammer and the overall stability of the excavations. Any evidence of seepage or other groundwater conditions were also noted. The location of the exploratory test pits and groundwater monitoring wells are shown on the included Test Pit Location Map. The following paragraphs briefly summarize the subsurface soils and conditions observed in the exploratory test pits excavated for the field investigation. The soil horizons are described as they were encountered in the test pit excavations, starting with the horizon nearest the surface and proceeding with each additional horizon encountered with depth. Please refer to the attached test pit logs for more detailed information. The first soil horizon encountered in each exploratory excavation was a Silty Clay Organic Soil of Low plasticity (OL). This material was dark brown to black in color, moist and soft. This material was encountered to depths varying from approximately 0.5 feet to 1.0 feet below grounds surface (bgs) in the exploratory excavations. Organic soils are highly compressible and are not suitable for foundation support. This material must be removed from beneath all foundation elements and in any area that will receive asphalt and/or concrete pavements. Underlying the Organic Soil in each exploratory excavation was a Sandy Lean Clay (CL). This material was present to depths varying from approximately 2.0 feet to 3.5 feet bgs. Penetration tests performed on this material with a static cone penetrometer indicate that it is soft to medium stiff in consistency. This material was brown in color, and moist. Rocky Mountain Flats, LLLP – Geotechnical Investigation – Fowler Lane, Gallatin County Montana January 30, 2025 Page 3 of 15 Underlying the Sandy Lean Clay in each exploratory excavation was a Poorly Graded Gravel with Sand and Cobbles (GP). This material was present to the end of each excavation at depths varying from approximately 6.75 feet to 8.0 feet bgs. This material with medium dense to dense in consistency, moist, and grayish brown to brown in color. It should be noted that approximately 12-inches of Clayey Gravel with Sand and Cobbles was encountered following the Sandy Lean Clay in TP-5 and TP-6. Subsurface Soil and Conditions – Geotechnical Borings On January 8th, 9th, and 10th of 2025, a member of the staff of IMEG visited the site to conduct an additional subsurface soils investigation. The subsurface soils investigation consisted of drilling seven soil borings. The exploratory borings were completed with a Mobile B-60X Drill Rig equipped with a hollow stem auger provided by O’Keefe Drilling. The boring locations were chosen based on the location of underground utilities, accessibility, and the desired building locations. The samples obtained from the soil borings were logged and visually classified according to ASTM D 2488, which utilizes the nomenclature of the Unified Soil Classification System (USCS). In addition, drilling reactions were observed to further aid in assessing the subsurface soils. Standard Penetration tests were performed at 2.5-to-5-foot intervals in accordance with ASTM D 1586. The standard penetration test involves driving a standard 2-inch (outside diameter) split-barrel sampler a total distance of 1.5 feet below the tip of the hollow stem auger utilizing a 140-pound hammer that is dropped a distance of 30 inches onto the sampler (each drop is considered 1 blow). The number of blows required to drive the sampler the last foot of penetration is recorded as an index of the soils strength. In the event that the sampler could not be driven 6 inches with 50 blows, the distance the sampler was driven with 50 blows was recorded. When this situation occurs in the first 6 inches of drive, it was noted as having occurred during the "set". Any evidence of seepage or other groundwater conditions were also noted. The locations of the borings are shown on the included Boring Location Map. The following paragraphs briefly summarize the subsurface soils and conditions observed in the exploratory borings drilled for the field investigation. The soil horizons are described as they were encountered in the borings, starting with the horizon nearest the surface and proceeding with each additional horizon encountered with depth. Please refer to the attached boring logs for more detailed information. The first soil horizon encountered in each exploratory boring was a Silty Clay Organic Soil of Low plasticity (OL). This material was dark brown to black in color, moist and soft. This material was encountered to depths varying from approximately 0.5 feet to 1.0 feet below grounds surface (bgs) in the exploratory excavations. Organic soils are highly compressible and are not suitable for foundation support. This material must be removed from beneath all foundation elements and in any area that will receive asphalt and/or concrete pavements. Rocky Mountain Flats, LLLP – Geotechnical Investigation – Fowler Lane, Gallatin County Montana January 30, 2025 Page 4 of 15 The second soil horizon encountered in each exploratory boring was a Sandy Lean Clay (CL). This material was dark brown to brown in color, moist, and soft to medium stiff in consistency. This material was encountered to depths varying from approximately 2.0 feet bgs to 3.0 feet bgs. The third soil horizon encountered in each exploratory boring was a Poorly Graded Gravel with Sand and Cobbles (GP). This material was present to the end of each boring at depths varying from approximately 9.0 feet to 25.8 feet bgs. This material with medium dense to very dense in consistency, moist to wet, and grayish brown to brown in color. Based on the subsurface investigation, it is recommended that the loads from the proposed structures be transmitted to the Poorly Graded Gravel with Sand and Cobbles or to a structural fill pad overlying this material. Groundwater Groundwater was encountered within each of the exploratory excavations and borings. Groundwater monitoring performed by IMEG from early April 2022 through August 2022 indicated that the seasonally high groundwater elevation across the subject property varies from 2.42 feet bgs to 3.53 feet bgs. The highest groundwater levels were found on the north half of the property. During this monitoring period all seven monitoring wells peaked on June 3, 2022. Please note that our subsurface investigation is not a detailed groundwater study, and groundwater conditions may change dramatically due to conditions that are out of our control. Our assessment of the groundwater conditions is based on the conditions observed within the exploratory excavations and borings on the days of the field exploration, our general experience in the project area, and the groundwater monitoring completed in 2022. This data is provided as an attachment to this report. Natural Resources Conservation Service Soil Survey The Natural Resources Conservation Service (NRCS) Web Soil Survey (WSS) provides soil data and information produced by the National Cooperative Soil Survey. The NRCS has determined the physical characteristics and engineering properties, among other data, of near surface soils across the United States. This data is reviewed against our observations and analysis of the subsurface soils encountered during the field investigation to determine if a correlation is present. If a strong correlation is determined, it is likely that other engineering properties or characteristics described by the NRCS regarding the soils present on the subject property are accurate as well. It should be noted that the NRCS typically only describes the soils located within 5 feet of the surface. NRCS Soil Survey information of the area was taken from the NRCS WSS, Version 2.0. For more information, please visit the NRCS Web Soil Survey on the World Wide Web, at http://websoilsurvey.nrcs.usda.gov/app/. The NRCS Soils Survey identifies two soil types across the Rocky Mountain Flats, LLLP – Geotechnical Investigation – Fowler Lane, Gallatin County Montana January 30, 2025 Page 5 of 15 subject property. The first soil type is 448A – Hyalite-Beaverton Complex. The NRCS describes this soil type as Loamy Alluvium. The second soil type is 457A – Turner Loam. The NRCS describes this soil type as Alluvium. Geologic Setting The following paragraphs discuss the geologic setting in the direct vicinity of the subject property. The geologic setting is determined from a review of surface geology maps and reports published by the United States Geological Survey and others that contain the subject property. This information is especially helpful in determining any geologic hazards that may be present in the immediate area (such as landslide deposits) and what types of soil and rock may be present in the area. Additional information regarding the parent material and depositional environment of a given soil type can also sometimes be obtained or inferred from these maps and reports. The local surface geology in the direct vicinity of the subject property was determined from the USGS Surface Geologic Map of the Eastern Part of The Gallatin Valley. The USGS Geological Map identifies the surface geology in the vicinity of the project site as Qabo – Older Alluvium of Braid Plains: “Well-rounded, moderately to well-sorted, bouldery gravel with interbedded silt. Underlies the northern part of the “Bozeman Fan” (Hackett and others, 1960). Deposited on and possibly incised into a pediment surface developed on Sixmile Creek Formation, but too thick to call pediment gravel. Probably deposited as glacial outwash during an early Pleistocene glacial period. Poorly exposed, but well logs suggest it is 15-30 feet (4-9 meters) thick. Groundwater in this unit is perched above the pediment surface and is found at shallow depths, limiting effectiveness and advisability of septic systems (Custer and others, 2001) and may hinder construction.” Seismicity The general Gallatin County area is located in an earthquake zone known as the intermountain seismic belt, which is a zone of earthquake activity that extends from northwest Montana to southern Arizona. In general, this zone is expected to experience moderately frequent, potentially damaging earthquakes. With that in mind, it is important that the structure be designed to withstand horizontal seismic accelerations that may be induced by such an earthquake, as is required by the International Building Code. The USGS provides seismic design parameters for the design of buildings and bridges across the United States. These parameters are based on the 2015 National Earthquake Hazards Reduction Program (NEHRP) Recommended Seismic Provisions. The primary intent of the NEHRP Recommended Seismic Provisions is to prevent, for typical buildings and structures, serious injury and life loss caused by damage from earthquake ground shaking. The following seismic design parameters were determined for the subject property using the USGS Seismic Design Application: Rocky Mountain Flats, LLLP – Geotechnical Investigation – Fowler Lane, Gallatin County Montana January 30, 2025 Page 6 of 15 Approximate site Location: Latitude = 45.6432° N Longitude = 111.0816° W Maximum Considered Earthquake (MCE) Spectral Response Acceleration Parameters: Short Period (SS) = 0.684g 1-Second Period (S1) = 0.216g Site Coefficients and Adjusted MCE Spectral Response Acceleration Parameters: SMS = 0.857g SM1 = 0.468g Design Spectral Response Acceleration Parameters: SDS = 0.571g SD1 = 0.312g The seismic site class for this project is D. Liquefaction In general terms, liquefaction is defined as the condition when saturated, loose, fine sand-type soils lose their support capabilities due to the development of excessive pore water pressure, which can develop during a seismic event. Loose silty sandy soils, if located below the groundwater table, have the potential to liquefy during a major seismic event. Our subsurface investigation did not encounter any loose sand or silt horizons within the depth of excavation that will be located within the water table, and it is our opinion that the potential for differential settlement resulting from liquefaction during a moderate seismic event is low. Foundation Recommendations Based on the subsurface soils encountered in the exploratory excavations and exploratory borings, it will be acceptable to utilize a slab-on-grade with stem wall foundation, provided the recommendations made in this report are properly implemented. Please find the following as general recommendations for all foundation elements: • In order to keep the footing out of the active frost zone it is recommended that the bottom of all footing elevations be a minimum of 48 inches below finished grade. Rocky Mountain Flats, LLLP – Geotechnical Investigation – Fowler Lane, Gallatin County Montana January 30, 2025 Page 7 of 15 • All foundation footings are to bear on the Poorly Graded Gravel with Sand and Cobbles or on a structural fill pad overlying this material. All foundation footings shall be dimensioned for an allowable bearing capacity of 3,000 pounds per square foot (psf). • It is recommended that typical strip footings for this structure have a minimum width of 16 inches and column footings should have a minimum width of 24 inches, provided the soils allowable bearing capacity is not exceeded. • The foundation subgrade must remain in a dry condition throughout construction of the foundation elements. • If construction takes place during the colder months of the year, the subgrade must be protected from freezing. This may require the use of insulating blankets and/or ground heaters. Allowable Bearing Capacity The bearing capacity of a soil is defined as the ultimate pressure per unit area by the foundation that can be supported by the soil in excess of the pressure caused by the surrounding soil at the footing level. Bearing capacity is determined by the physical and chemical properties of the soil located beneath the proposed structures footings. It is recommended that the loads from the proposed structure be transmitted to the Poorly Graded Gravel with Sand and Cobbles or on to a structural fill pad overlying this material. For this scenario it is recommended that an allowable bearing capacity of 3,000 pounds per square foot be used to dimension all foundation footings. Settlement While the soil at the site may be able to physically support the footings, it is also important to analyze the possible settlement of the structure. In many cases, settlement determines the allowable bearing capacity. When a soil deposit is loaded by a structure, deformations within the soil deposit will occur. The total vertical deformation of the soil at the surface is called total settlement. Total settlement is made up of two components: elastic settlement and consolidation settlement. Elastic settlement is the result of soil particles rearranging themselves into a denser configuration due to a load being imposed on them and usually occurs during the construction process and shortly after. Consolidation settlement occurs more slowly and over time as water within the pore spaces of a soil are forced out and the soil compresses as the stress from the load is transferred from the water molecules to the soil particles. Consolidation settlement is more of a concern with fine-grained soils with low permeability and high in-situ moisture contents. The degree of settlement is a function of the type of bearing material, the bearing pressure of Rocky Mountain Flats, LLLP – Geotechnical Investigation – Fowler Lane, Gallatin County Montana January 30, 2025 Page 8 of 15 the foundation elements, local groundwater conditions, and in some cases determines the allowable bearing capacity for a structures’ footings. In addition to analyzing total settlement, the potential for differential settlement must also be considered. Differential settlement occurs in soils that are not homogeneous over the length of the foundation or in situations where the foundation rests on cut and fill surfaces. If the foundation rests on structural fill overlaying properly prepared soils with rock, differential settlement is expected to be well within tolerable limits. Areas that have significantly more fill under the foundation footings (four feet of more) create greater potential for differential settlement. In these cases, the structural fill must be installed properly and tested frequently. Compaction efforts and structural fill consistence are vital in minimizing differential settlement. For this project it is not anticipated that significant quantities of structural fill will be required. For this project, total settlement is expected to consist of elastic settlement. A settlement analysis based on conservative soil parameter estimates, the recommended allowable bearing capacity, and the assumption that all recommendations made in this report are properly adhered to, indicates the total and differential settlement are expected to be ¾-inch or less. Structures of the type assumed can generally tolerate this amount of movement, however, these values should be checked by a structural engineer to verify that they are acceptable. Please note that the settlement estimates are based on loads originating from the proposed structure. If additional loads are introduced, such as the placement of large quantities of fill, our office should be contacted to re-evaluate the settlement estimates. Lateral Pressures Lateral pressures imposed upon foundation and retaining walls due to wind, seismic forces, and earth pressures may be resisted by the development of passive earth pressures and/or frictional resistance between the base of the footings and the supporting soils. If a foundation or retaining wall is restrained from moving, the lateral earth pressure exerted on the wall is called the at-rest earth pressure. If a foundation or retaining wall is allowed to tilt away from the retained soil, the lateral earth pressure exerted on the wall is called the active earth pressure. Passive earth pressure is the resistance pressure the foundation or retaining wall develops due to the wall being pushed laterally into the earth on the opposite side of the retained soil. Each of these pressures is proportional to the distance below the earth surface, the unit weight of the soil, and the shear strength properties of the soil. It is recommended that all foundation and retaining walls be backfilled with well-draining granular material. Well-draining granular backfill has a more predictable behavior in terms of the lateral earth pressure exerted on the foundation or retaining wall and will not generate expansive related forces. If backfill containing significant quantities of clayey material is used, the seepage of water into the backfill could potentially generate horizontal swelling pressures well above at-rest values. Additionally, seepage into a clayey backfill Rocky Mountain Flats, LLLP – Geotechnical Investigation – Fowler Lane, Gallatin County Montana January 30, 2025 Page 9 of 15 material will also cause significant hydrostatic pressures to build up against the foundation wall due to the low permeability of clay soils and will make the backfill susceptible to frost action. Subsurface walls that are restrained from moving at the top are recommended to be designed for an equivalent fluid pressure of 60 pounds per cubic foot (pcf) (at-rest pressure); the equivalent fluid pressure is the product of the retained soils unit weight and its coefficient of active or at-rest earth pressure. Any subsurface walls that are allowed to move away from the restrained soil, such as cantilevered retaining walls, are recommended to be designed for an equivalent fluid pressure of 45 pcf (active pressure). For passive pressures, an equivalent fluid pressure of 300 pcf is recommended, and the coefficient of friction between the cast-in-place concrete and the Poorly Graded Gravel with Sand and Cobbles is 0.5. These recommended values were calculated assuming a near horizontal backfill and that the on-site soils with the exceptions of the organics, will be used as foundation wall backfill. It is also assumed that the backfill will be compacted as recommended in this report. Also, please note that these design pressures do not include a factor of safety and are for static conditions, they do not account for additional forces that may be induced by seismic loading. Subgrade Preparation and Structural Fill In general, the excavation for the foundation footings must be level and uniform and continue down through any organics and Sandy Lean Clay to the Poorly Graded Gravel with Sand and Cobbles. If any soft spots or boulders are encountered, they will need to be removed and backfilled with structural fill. The excavation width must extend a minimum of one footing width from the outside edges of the footings or to a distance equal to ½ the height of the required structural fill. For example, if 4 feet of structural fill is required under the foundation footings, the excavation width must extend out a minimum distance of 2 feet from the outside edges of the foundation footings. Once the excavation is complete, the native subgrade shall be compacted to an unyielding condition with a large smooth drum roller. Any areas that are found to rut or pump shall be sub-excavated and replaced with structural fill. Structural fill is defined as all fill that will ultimately be subjected to structural loadings, such as those imposed by footings, floor slabs, pavements, etc. The Poorly Graded Gravel with Sand and Cobbles encountered during the field investigations is suitable for reuse as structural fill, provided it is not too moist and any cobbles larger than 3 inches in size are removed. Structural fill may also be imported if required. Imported structural fill is recommended to be a well graded gravel with sand that contains less than 15 percent of material that will pass a No. 200 sieve and that has a maximum particle size of 3 inches. Also, the fraction of material passing the No. 40 sieve shall have a liquid limit not exceeding 25 and a plasticity index not exceeding 6. The gravel and sand particles also need to be made up of durable rock materials that will not degrade when compacted; no shale or mudstone fragments should be present. Rocky Mountain Flats, LLLP – Geotechnical Investigation – Fowler Lane, Gallatin County Montana January 30, 2025 Page 10 of 15 Structural fill must be placed in lifts no greater than 12-inches (uncompacted thickness) and be uniformly compacted to a minimum of 97 percent of its maximum dry density, as determined by ASTM D698. Typically, the structural fill must be moisture conditioned to within + 2 percent of the materials optimum moisture content to achieve the required density. It is recommended that the structural fill be compacted with a large vibrating smooth drum roller. Please note that if a moisture-density relationship test (commonly referred to as a proctor) needs to be performed for a proposed structural fill material to determine its maximum dry density in accordance with ASTM D698, a sample of the material must be delivered to this office a minimum of three full working days prior to density testing being needed. At no time should surface water runoff be allowed to flow into and accumulate within the excavation for the foundation elements. If necessary, a swale or berm should be temporarily constructed to reroute all surface water runoff away from the excavation. Excavation should not proceed during large precipitation events. If any of the foundation footings are found to be located on a test pit, the area will need to be excavated down to the full depth of the test pit and structural fill be placed and compacted in controlled lifts as described in this report to bring the area back up to the desired grade. Foundation Wall Backfill Approved backfill material should be placed and compacted between the foundation wall and the edge of the excavation. Structural fill is recommended as foundation wall backfill in all areas that will support concrete slabs-on-grade or asphalt paving improvements. The on-site soils with the exception of the organics encountered during the field investigation are suitable for reuse as foundation wall backfill along the exterior of the foundation where asphalt and concrete pavements will not be located, provided it is not too moist and any cobbles larger than 6 inches in size are removed. The organic soil shall not be used as foundation wall backfill. The foundation wall backfill shall be placed in uniform lifts and be compacted to a minimum of 95 percent of the material’s maximum dry density, as determined by ASTM D698. The foundation wall backfill will need to be compacted with either walk behind compaction equipment or hand operated compaction equipment in order to avoid damaging the foundation walls. If walk behind compaction equipment is used lifts should not exceed 8-inches (loose thickness) and if hand operated compaction equipment is used lifts should not exceed 4-inches (loose thickness). Interior Slabs-on-Grade For any interior slabs-on-grade, it is recommended that, at a minimum, the organic soil be removed. The native subgrade then needs to be compacted to a minimum of 95 percent of its maximum dry density, as determined by ASTM D698. Following compaction of the native subgrade, a layer of separation geotextile Rocky Mountain Flats, LLLP – Geotechnical Investigation – Fowler Lane, Gallatin County Montana January 30, 2025 Page 11 of 15 (such as a Mirafi 160N) shall be installed, structural fill can then be placed and compacted to within 6- inches of the desired bottom of slab elevation. For all interior concrete slabs-on-grade, preventative measures must be taken to stop moisture from migrating upwards through the slab. Moisture that migrates upwards through the concrete slab can damage floor coverings such as carpet, hardwood, and vinyl, in addition to causing musty odors and mildew growth. Moisture barriers will need to be installed to prevent water vapor migration and capillary rise through the concrete slab. Capillarity is the result of the liquid property known as surface tension, which arises from an imbalance of cohesive and adhesive forces near the interface between different materials. With regards to soils, surface tension arises at the interface between groundwater and the mineral grains and air of a soil. The height of capillary rise within a given soil is controlled by the size of the pores between the soil particles and not the size of the soil particles directly. Soils that have small pore spaces experience a higher magnitude of capillary rise than soils with large pore spaces. Typically, soils composed of smaller particles (such as silt and clay) have smaller pore spaces. In order to prevent capillary rise through the concrete slab-on-grade it is recommended that 6 inches of ¾- inch washed rock (containing less than 10 percent fines) be placed and compacted once the excavation for the slab is complete. The washed rock has large pore spaces between soil particles and will act as a capillary break, preventing groundwater from migrating upwards towards the bottom of the slab. Water vapor is currently understood to act in accordance with the observed physical laws of gases, which state that the water vapor will travel from an area of higher concentration to that of a lower concentration until equilibrium is achieved. Because Earth contains large quantities of liquid water, water vapor is ubiquitous in Earth’s atmosphere, and, as a result, also in soils located above the water table (referred to as the vadose zone). Typically, the concentration of water vapor in the vadose zone is greater than that inside the residence. This concentration difference may result in an upward migration of water vapor from the vadose zone through the concrete slab-on-grade and into the building. In order to prevent this upward migration of water vapor through the slab, it is recommended that a 15-mil extruded polyolefin plastic that complies with ASTM E1745 (such as a Stego Wrap 15-mil Vapor Barrier) be installed. The vapor barrier should be pulled up at the sides and secured to the foundation wall or footing. Care must be taken during and after the installation of the vapor barrier to avoid puncturing the material, and all joints are to be sealed per the manufacture’s recommendations. Once the excavation for any interior slabs-on-grade is completed as described in the first paragraph of this section, and the ¾ inch washed rock and moisture barriers have been properly installed, it will be acceptable to form and cast the steel reinforced concrete slab. It is recommended that interior concrete slabs-on-grade have a minimum thickness of 4 inches, provided all slab reinforcement is designed by a licensed structural engineer. Rocky Mountain Flats, LLLP – Geotechnical Investigation – Fowler Lane, Gallatin County Montana January 30, 2025 Page 12 of 15 Exterior Slabs-on-Grade For exterior areas to be paved with concrete slabs such as sidewalks and/or patios, it is recommended that, at a minimum, the organic soil be removed. The subgrade then needs to be compacted to a minimum of 95 percent of its maximum dry density, as determined by ASTM D698. Then for non-vehicular traffic areas, a minimum of 6 inches of ¾-inch minus rock needs to be placed, and 4 inches of 4000 pounds per square inch (psi) concrete placed over the ¾-inch minus rock. For areas with vehicular traffic, a minimum of 9 inches of ¾-inch minus rock should be placed, followed by 6 inches of 4000 psi concrete. Exterior slabs that will be located adjacent to the foundation walls need to slope away from the structure at a minimum grade of 2 percent and should not be physically connected to the foundation walls. If they are connected, any movement of the exterior slab will be transmitted to the foundation wall, which may result in damage to the structure. Site Grading Surface water should not be allowed to accumulate and infiltrate the soil near the foundation. Proper site grading will ensure surface water runoff is directed away from the foundation elements and will aid in the mitigation of excessive settlement. Please find the following as general site grading recommendations: • Finished grade must slope away from the building a minimum of 5 percent within the first 10 feet, in order to quickly drain ground surface and roof runoff away from the foundation walls. Please note that in order to maintain this slope; it is imperative that any backfill placed against the foundation walls be compacted properly. If the backfill is not compacted properly, it will settle and positive drainage away from the structure will not be maintained. • Permanent sprinkler heads for lawn care should be located a sufficient distance from the structure to prevent water from draining toward the foundation or saturating the soils adjacent to the foundation. • Rain gutter down spouts are to be placed in such a manner that surface water runoff drains away from the structure. • All roads, walkways, and architectural land features must properly drain away from all structures. Special attention should be made during the design of these features to not create any drainage obstructions that may direct water towards or trap water near the foundation. Asphalt Paving Improvements For areas to be paved with asphalt, it is recommended that, as a minimum, the organic soil be removed. The native subgrade then needs to be compacted at ± 2 percent of its optimum moisture content to 95 percent of its maximum dry density. Following compaction of the native subgrade, a layer of separation Rocky Mountain Flats, LLLP – Geotechnical Investigation – Fowler Lane, Gallatin County Montana January 30, 2025 Page 13 of 15 geotextile (such as a Mirafi 160N) shall be installed followed by a 12-inch layer of compacted 6-inch minus gravel. Next by a 6-inch layer of compacted 1-inch minus road mix shall be installed. Both gravel courses must be compacted at ± 2 percent of their optimum moisture content to 95 percent of their maximum dry density. A 3-inch-thick layer of asphalt pavement can then be placed and compacted over this cross- section. If asphalt paving is to be placed on foundation wall backfill, the backfill must be compacted to 95 percent of its maximum dry density, as determined by ASTM D698. It is recommended the backfill be placed in uniform lifts and be compacted to an unyielding condition. Underground Utilities We recommend specifying non-corrosive materials or providing corrosion protection unless additional tests are performed to verify the onsite soils are not corrosive. It is recommended that ¾-inch minus gravel be used as a bedding material, where bedding material is defined as all material located within 6 inches of the utility pipe(s). The bedding material should be thoroughly compacted around all utility pipes. Trench backfill shall be compacted to a minimum of 95 percent of its maximum dry density in paved or landscaped areas and a minimum of 97 percent of its maximum dry density beneath foundation footings. Backfilling around and above utilities shall meet the requirements of Montana Public Works Standard Specifications. Construction Administration The foundation is a vital element of a structure; it transfers all of the structure’s dead and live loads to the native soil. It is imperative that the recommendations made in this report are properly adhered to. A representative from IMEG should observe the construction of any foundation or drainage elements recommended in this report. The recommendations made in this report are contingent upon our involvement. If the soils encountered during the excavation differ than those described in this report or any unusual conditions are encountered, our office should be contacted immediately to examine the conditions, re-evaluate our recommendations and provide a written response. If construction and site grading take place during cold weather, it is recommended that appropriate winter construction practices be observed. All snow and ice shall be removed from cut and fill areas prior to site grading taking place. No fill should be placed on soils that are frozen or contain frozen material. No frozen soils can be used as fill under any circumstances. Additionally, Concrete should not be placed on frozen soils and should meet the temperature requirements of ASTM C 94. Any concrete placed during cold weather conditions shall be protected from freezing until the necessary compressive strength has been attained. Once the footings are placed, frost shall not be permitted to extend below the foundation footings, as this could heave and crack the foundation footings and/or foundation walls. It is the responsibility of the contractor to provide a safe working environment with regards to excavations on the site. All excavations should be sloped or shored in the interest of safety and in accordance with Rocky Mountain Flats, LLLP – Geotechnical Investigation – Fowler Lane, Gallatin County Montana January 30, 2025 Page 14 of 15 local and federal regulations, including the excavation and trench safety standards provided by the Occupational Safety and Health Administration (OSHA). Report Limitations and Guidelines for Use This report was prepared to be used exclusively by Rocky Mountain Flats, LLLP for residential improvements to be constructed on the N½, S½, SW¼, SW¼ of Section 23, located in the Southwest Quarter of Section 23, Township 2 South, Range 5 East in Gallatin County, Montana. All of the work was performed in accordance with generally accepted principles and practices used by geotechnical engineers and geologists practicing in this or similar localities. This report should not be used by anyone it was not prepared for, or for uses it was not intended for. Field investigations and preparation of this report was conducted in accordance with a specific set of requirements set out by the client, which may not satisfy the requirements of others. This report should not be used for nearby sites or for structures on the same site that differ from the structures that were proposed at the time this report was prepared. Any changes in the structures (type, orientation, size, elevation, etc.) proposed for this site must be discussed with our company for this report to be valid. The recommendations made in this report are based upon data obtained from the exploratory borings and test pits excavated at the locations indicated on the attached Test Pit and Boring Location Maps. It is not uncommon that variations will occur between these locations, the nature and extent of which will not become evident until additional exploration or construction is conducted. These variations may result in additional construction costs, and it is suggested that a contingency be provided for this purpose. If the soils encountered during the excavation differ than those described in this report or any unusual conditions are encountered, our office should be contacted immediately to examine the conditions and re-evaluate our recommendations and provide a written response. This report is valid as a complete document only. No portion of this report should be transmitted to other parties as an incomplete document. Misinterpretation of portions of this report (i.e. test pit logs) is possible when this information is transmitted to others without the supporting information presented in other portions of the report. The scope of our investigation did not include an environmental assessment for determining the presence or absence of hazardous or toxic materials on the site. If information regarding the potential presence of hazardous materials on the site is desired, please contact us to discuss your options for obtaining this information. If any questions arise with regards to any aspects of this report, please contact us at your convenience to avoid misinterpretation. Costly mistakes due to misinterpretation of geotechnical reports can usually be avoided by a quick phone call. OL CL GP 1.0 2.0 6.8 0 TO 1 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 1 TO 2 FEET: SANDY LEAN CLAY; (CL); brown; moist; medium stiff; approximately 10percent subrounded gravels; approximately 40 percent fine to coarse grain sand; approximately 50 percent clayey fines. 2 TO 6.75 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); grayish brown to brown; moist; medium dense to dense; approximately 50 percent subrounded gravels; approximately 40 percent fine to coarse grain sand; approximately 10 percentclayey fines. Bottom of test pit at 6.8 feet. NOTES GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. EXCAVATION METHOD Tracked Excavator EXCAVATION CONTRACTOR RLS Construction GROUND WATER LEVELS: DATE STARTED 12/21/21 COMPLETED 12/21/21 AT TIME OF EXCAVATION 6.75 ft AFTER EXCAVATION --- AT END OF EXCAVATION ---DEPTH(ft)0.0 2.5 5.0 SAMPLE TYPENUMBERPAGE 1 OF 1 TEST PIT NUMBER TP 1 PROJECT NUMBER 211431 CLIENT Bridger Land Group PROJECT LOCATION 5532 Fowler Lane PROJECT NAME Geotechnical Investigation Report GENERAL BH / TP / WELL - GINT STD US.GDT - 1/29/25 14:27 - C:\USERS\NOAH.J.SCHAIBLE\ONEDRIVE - IMEG CORP\DESKTOP\GEOTECH PROOJECTS\FOWLER DRILLING PROJECT\TEST PIT LOGS (211431).GPJU.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION OL CL GP 1.0 2.0 6.8 0 TO 1 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 1 TO 2 FEET: SANDY LEAN CLAY; (CL); brown; moist; medium stiff; approximately 10percent subrounded gravels; approximately 30 percent fine to coarse grain sand; approximately 60 percent clayey fines. 2 TO 6.75 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); grayish brown to brown; moist; medium dense to dense; approximately 50 percent subrounded gravels; approximately 40 percent fine to coarse grain sand; approximately 10 percentclayey fines. Bottom of test pit at 6.8 feet. NOTES GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. EXCAVATION METHOD Tracked Excavator EXCAVATION CONTRACTOR RLS Construction GROUND WATER LEVELS: DATE STARTED 12/21/21 COMPLETED 12/21/21 AT TIME OF EXCAVATION 6.75 ft AFTER EXCAVATION --- AT END OF EXCAVATION ---DEPTH(ft)0.0 2.5 5.0 SAMPLE TYPENUMBERPAGE 1 OF 1 TEST PIT NUMBER TP 2 PROJECT NUMBER 211431 CLIENT Bridger Land Group PROJECT LOCATION 5532 Fowler Lane PROJECT NAME Geotechnical Investigation Report GENERAL BH / TP / WELL - GINT STD US.GDT - 1/29/25 14:27 - C:\USERS\NOAH.J.SCHAIBLE\ONEDRIVE - IMEG CORP\DESKTOP\GEOTECH PROOJECTS\FOWLER DRILLING PROJECT\TEST PIT LOGS (211431).GPJU.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION OL CL GP 1.0 3.0 7.0 0 TO 1 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 1 TO 3 FEET: SANDY LEAN CLAY; (CL); brown; moist; medium stiff; approximately 10percent subrounded gravels; approximately 30 percent fine to coarse grain sand; approximately 60 percent clayey fines. 3 TO 7 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); grayish brown to brown; moist; medium dense to dense; approximately 50 percent subrounded gravels; approximately 40 percent fine to coarse grain sand; approximately 10 percent clayey fines. Bottom of test pit at 7.0 feet. NOTES GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. EXCAVATION METHOD Tracked Excavator EXCAVATION CONTRACTOR RLS Construction GROUND WATER LEVELS: DATE STARTED 12/21/21 COMPLETED 12/21/21 AT TIME OF EXCAVATION 7.00 ft AFTER EXCAVATION --- AT END OF EXCAVATION ---DEPTH(ft)0.0 2.5 5.0 SAMPLE TYPENUMBERPAGE 1 OF 1 TEST PIT NUMBER TP 3 PROJECT NUMBER 211431 CLIENT Bridger Land Group PROJECT LOCATION 5532 Fowler Lane PROJECT NAME Geotechnical Investigation Report GENERAL BH / TP / WELL - GINT STD US.GDT - 1/29/25 14:27 - C:\USERS\NOAH.J.SCHAIBLE\ONEDRIVE - IMEG CORP\DESKTOP\GEOTECH PROOJECTS\FOWLER DRILLING PROJECT\TEST PIT LOGS (211431).GPJU.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION OL CL GP 1.0 3.5 7.0 0 TO 1 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 1 TO 3.5 FEET: SANDY LEAN CLAY; (CL); brown; moist; medium stiff; approximately 10percent subrounded gravels; approximately 30 percent fine to coarse grain sand; approximately 60 percent clayey fines. 3.5 TO 7 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); grayishbrown to brown; moist; medium dense to dense; approximately 50 percent subrounded gravels; approximately 40 percent fine to coarse grain sand; approximately 10 percent clayey fines. Bottom of test pit at 7.0 feet. NOTES GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. EXCAVATION METHOD Tracked Excavator EXCAVATION CONTRACTOR RLS Construction GROUND WATER LEVELS: DATE STARTED 12/21/21 COMPLETED 12/21/21 AT TIME OF EXCAVATION 7.00 ft AFTER EXCAVATION --- AT END OF EXCAVATION ---DEPTH(ft)0.0 2.5 5.0 SAMPLE TYPENUMBERPAGE 1 OF 1 TEST PIT NUMBER TP 4 PROJECT NUMBER 211431 CLIENT Bridger Land Group PROJECT LOCATION 5532 Fowler Lane PROJECT NAME Geotechnical Investigation Report GENERAL BH / TP / WELL - GINT STD US.GDT - 1/29/25 14:27 - C:\USERS\NOAH.J.SCHAIBLE\ONEDRIVE - IMEG CORP\DESKTOP\GEOTECH PROOJECTS\FOWLER DRILLING PROJECT\TEST PIT LOGS (211431).GPJU.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION OL CL GC GP 1.0 3.0 4.5 8.0 0 TO 1 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 1 TO 3 FEET: SANDY LEAN CLAY; (CL); brown; moist; medium stiff; approximately 10percent subrounded gravels; approximately 30 percent fine to coarse grain sand; approximately 60 percent clayey fines. 3 TO 4.5 FEET: CLAYEY GRAVEL WITH SAND AND COBBLES; (GC); brown; moist; medium dense; approximately 40 percent subrounded gravels; approximately 30 percent fine to coarse grain sand; approximately 30 percent clayey fines. 4.5 TO 8 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); grayish brown to brown; moist; medium dense to dense; approximately 50 percent subrounded gravels; approximately 40 percent fine to coarse grain sand; approximately 10 percentclayey fines. Bottom of test pit at 8.0 feet. NOTES GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. EXCAVATION METHOD Tracked Excavator EXCAVATION CONTRACTOR RLS Construction GROUND WATER LEVELS: DATE STARTED 12/21/21 COMPLETED 12/21/21 AT TIME OF EXCAVATION 7.50 ft AFTER EXCAVATION --- AT END OF EXCAVATION ---DEPTH(ft)0.0 2.5 5.0 7.5 SAMPLE TYPENUMBERPAGE 1 OF 1 TEST PIT NUMBER TP 5 PROJECT NUMBER 211431 CLIENT Bridger Land Group PROJECT LOCATION 5532 Fowler Lane PROJECT NAME Geotechnical Investigation Report GENERAL BH / TP / WELL - GINT STD US.GDT - 1/29/25 14:27 - C:\USERS\NOAH.J.SCHAIBLE\ONEDRIVE - IMEG CORP\DESKTOP\GEOTECH PROOJECTS\FOWLER DRILLING PROJECT\TEST PIT LOGS (211431).GPJU.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION OL CL GC GP 1.0 2.5 3.5 8.0 0 TO 1 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 1 TO 2.5 FEET: SANDY LEAN CLAY; (CL); brown; moist; medium stiff; approximately 10percent subrounded gravels; approximately 30 percent fine to coarse grain sand; approximately 60 percent clayey fines. 2.5 TO 3.5 FEET: CLAYEY GRAVEL WITH SAND AND COBBLES; (GC); brown; moist; medium dense; approximately 40 percent subrounded gravels; approximately 30 percent fine to coarse grain sand; approximately 30 percent clayey fines. 3.5 TO 8 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); grayishbrown to brown; moist; medium dense to dense; approximately 50 percent subrounded gravels; approximately 40 percent fine to coarse grain sand; approximately 10 percent clayey fines. Bottom of test pit at 8.0 feet. NOTES GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. EXCAVATION METHOD Tracked Excavator EXCAVATION CONTRACTOR RLS Construction GROUND WATER LEVELS: DATE STARTED 12/21/21 COMPLETED 12/21/21 AT TIME OF EXCAVATION 7.75 ft AFTER EXCAVATION --- AT END OF EXCAVATION ---DEPTH(ft)0.0 2.5 5.0 7.5 SAMPLE TYPENUMBERPAGE 1 OF 1 TEST PIT NUMBER TP 6 PROJECT NUMBER 211431 CLIENT Bridger Land Group PROJECT LOCATION 5532 Fowler Lane PROJECT NAME Geotechnical Investigation Report GENERAL BH / TP / WELL - GINT STD US.GDT - 1/29/25 14:27 - C:\USERS\NOAH.J.SCHAIBLE\ONEDRIVE - IMEG CORP\DESKTOP\GEOTECH PROOJECTS\FOWLER DRILLING PROJECT\TEST PIT LOGS (211431).GPJU.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION OL CL GP 1.0 2.5 7.8 0 TO 1 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 1 TO 2.5 FEET: SANDY LEAN CLAY; (CL); brown; moist; medium stiff; approximately 10percent subrounded gravels; approximately 30 percent fine to coarse grain sand; approximately 60 percent clayey fines. 2.5 TO 7.75 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); grayish brown to brown; moist; medium dense to dense; approximately 50 percent subrounded gravels; approximately 40 percent fine to coarse grain sand; approximately 10 percent clayey fines. Bottom of test pit at 7.8 feet. NOTES GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. EXCAVATION METHOD Tracked Excavator EXCAVATION CONTRACTOR RLS Construction GROUND WATER LEVELS: DATE STARTED 12/21/21 COMPLETED 12/21/21 AT TIME OF EXCAVATION 7.50 ft AFTER EXCAVATION --- AT END OF EXCAVATION ---DEPTH(ft)0.0 2.5 5.0 7.5 SAMPLE TYPENUMBERPAGE 1 OF 1 TEST PIT NUMBER TP 7 PROJECT NUMBER 211431 CLIENT Bridger Land Group PROJECT LOCATION 5532 Fowler Lane PROJECT NAME Geotechnical Investigation Report GENERAL BH / TP / WELL - GINT STD US.GDT - 1/29/25 14:27 - C:\USERS\NOAH.J.SCHAIBLE\ONEDRIVE - IMEG CORP\DESKTOP\GEOTECH PROOJECTS\FOWLER DRILLING PROJECT\TEST PIT LOGS (211431).GPJU.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION SS2 SS 3 SS4 SS 5 SS6 SS7 61 56 61 78 100 89 6-17-19(36) 17-38-40 (78) 29-32-29(61) 18-32-33 (65) 18-50/2" 28-50/3" MC = 5%Fines = 18% MC = 3% Fines = 7% OL CL GP 1.0 2.0 20.8 0 TO 1 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 1 TO 2 FEET: SANDY LEAN CLAY; (CL); dark brown to brown; moist; medium plasticity; soft to medium stiff; approximately 30 percent fine to coarse grain sand; approximately 70 percentclayey fines. 2 TO 20.75 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); grayish brown to brown; moist to wet; dense to very dense; approximately 60 percent subrounded gravels; approximately 30 percent fine to coarse grain sand;approximately 10 percent clayey fines. Refusal at 20.8 feet. Bottom of borehole at 20.8 feet. NOTES Driller: Larry P. / Mike H., Partly Cloudy, Breezy, 20F GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. DRILLING METHOD B-60X Mobile Drill Rig DRILLING CONTRACTOR O'keefe Drilling GROUND WATER LEVELS: DATE STARTED 1/8/25 COMPLETED 1/8/25 AT TIME OF DRILLING 7.50 ft AFTER DRILLING --- AT END OF DRILLING ---DEPTH(ft)0 5 10 15 20 SAMPLE TYPENUMBERPAGE 1 OF 1 BORING NUMBER B1 PROJECT NUMBER 25000076.00 CLIENT Rocky Mountain Flats, LLLP PROJECT LOCATION 5532 Fowler Lane, Bozeman MT PROJECT NAME Geotechnical Investigation GENERAL BH / TP / WELL - GINT STD US.GDT - 1/28/25 14:49 - \\FILES\ACTIVE\PROJECTS\2025\25000076.00\DESIGN\CIVIL\GEOTECHNICAL\BORING LOGS\BORING LOGS (25000076.00).GPJRECOVERY %BLOWCOUNTS(N VALUE)TESTS U.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION SS11 SS12 SS 13 SS14 SS15 0 0 56 0 100 28-50/3" 50/4" 20-24-32 (56) 46-50/5" 50/4" OL CL GP 1.0 2.0 20.3 0 TO 1 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 1 TO 2 FEET: SANDY LEAN CLAY; (CL); dark brown to brown; moist; medium plasticity; soft to medium stiff; approximately 30 percent fine to coarse grain sand; approximately 70 percent clayey fines. 2 TO 20.33 FEET: POORLY GRADED GRAVEL WITH SAND ANDCOBBLES; (GP); grayish brown to brown; moist to wet; medium dense to very dense; approximately 60 percent subrounded gravels; approximately 30 percent fine to coarse grain sand; approximately 10 percent clayey fines. 15: NOTE: at approx. 15' bgs refusal on cobble/boulder, pulled auger to offset 4' and re-drilled boring. Refusal at 20.3 feet. Bottom of borehole at 20.3 feet. NOTES Driller: Larry P. / Mike H., Partly Cloudy, Breezy, 20F GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. DRILLING METHOD B-60X Mobile Drill Rig DRILLING CONTRACTOR O'keefe Drilling GROUND WATER LEVELS: DATE STARTED 1/8/25 COMPLETED 1/8/25 AT TIME OF DRILLING 7.50 ft AFTER DRILLING --- AT END OF DRILLING ---DEPTH(ft)0 5 10 15 20 SAMPLE TYPENUMBERPAGE 1 OF 1 BORING NUMBER B2 PROJECT NUMBER 25000076.00 CLIENT Rocky Mountain Flats, LLLP PROJECT LOCATION 5532 Fowler Lane, Bozeman MT PROJECT NAME Geotechnical Investigation GENERAL BH / TP / WELL - GINT STD US.GDT - 1/28/25 14:49 - \\FILES\ACTIVE\PROJECTS\2025\25000076.00\DESIGN\CIVIL\GEOTECHNICAL\BORING LOGS\BORING LOGS (25000076.00).GPJRECOVERY %BLOWCOUNTS(N VALUE)U.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION SS17 SS18 SS19 SS20 56 44 56 50 3-7-3(10) 8-25-25(50) 24-46-39(85) 26-27-20(47) MC = 4%Fines = 10% OL CL GP 0.7 2.0 9.0 0 TO 0.67 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 0.67 TO 2 FEET: SANDY LEAN CLAY; (CL); dark brown to brown; moist; medium plasticity; soft to medium stiff; approximately 30 percent fine to coarse grain sand; approximately 70 percent clayey fines. 2 TO 9 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); grayish brown to brown; moist to wet; dense to very dense; approximately 60 percent subrounded gravels; approximately 30 percent fine to coarse grain sand;approximately 10 percent clayey fines. Bottom of borehole at 9.0 feet. NOTES Driller: Larry P. / Mike H., Partly Cloudy, Breezy, 20F GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. DRILLING METHOD B-60X Mobile Drill Rig DRILLING CONTRACTOR O'keefe Drilling GROUND WATER LEVELS: DATE STARTED 1/8/25 COMPLETED 1/8/25 AT TIME OF DRILLING 7.50 ft AFTER DRILLING --- AT END OF DRILLING ---DEPTH(ft)0.0 2.5 5.0 7.5 SAMPLE TYPENUMBERPAGE 1 OF 1 BORING NUMBER B3 PROJECT NUMBER 25000076.00 CLIENT Rocky Mountain Flats, LLLP PROJECT LOCATION 5532 Fowler Lane, Bozeman MT PROJECT NAME Geotechnical Investigation GENERAL BH / TP / WELL - GINT STD US.GDT - 1/28/25 14:49 - \\FILES\ACTIVE\PROJECTS\2025\25000076.00\DESIGN\CIVIL\GEOTECHNICAL\BORING LOGS\BORING LOGS (25000076.00).GPJRECOVERY %BLOWCOUNTS(N VALUE)TESTS U.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION SS23 SS24 SS25 SS26 SS27 SS28 SS29 44 89 33 44 67 45 55 34-34-35(69) 24-40-30(70) 16-31-25(56) 11-25-30(55) 23-37-47(84) 38-50/5" 50/6" MC = 4%Fines = 11% OL CL GP 1.0 2.0 25.5 0 TO 1 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 1 TO 2 FEET: SANDY LEAN CLAY; (CL); dark brown to brown; moist; medium plasticity; soft to medium stiff; approximately 30 percent fine to coarse grain sand; approximately 70 percentclayey fines. 2 TO 25.46 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); grayish brown to brown; moist to wet; dense to very dense; approximately 60 percent subrounded gravels; approximately 30 percent fine to coarse grain sand;approximately 10 percent clayey fines. Bottom of borehole at 25.5 feet. NOTES Driller: Larry P. / Mike H., Partly Cloudy, Breezy, 20F GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. DRILLING METHOD B-60X Mobile Drill Rig DRILLING CONTRACTOR O'keefe Drilling GROUND WATER LEVELS: DATE STARTED 1/9/25 COMPLETED 1/9/25 AT TIME OF DRILLING 7.50 ft AFTER DRILLING --- AT END OF DRILLING ---DEPTH(ft)0 5 10 15 20 25 SAMPLE TYPENUMBERPAGE 1 OF 1 BORING NUMBER B4 PROJECT NUMBER 25000076.00 CLIENT Rocky Mountain Flats, LLLP PROJECT LOCATION 5532 Fowler Lane, Bozeman MT PROJECT NAME Geotechnical Investigation GENERAL BH / TP / WELL - GINT STD US.GDT - 1/28/25 14:49 - \\FILES\ACTIVE\PROJECTS\2025\25000076.00\DESIGN\CIVIL\GEOTECHNICAL\BORING LOGS\BORING LOGS (25000076.00).GPJRECOVERY %BLOWCOUNTS(N VALUE)TESTS U.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION SS31 SS32 SS33 SS34 SS 35 SS 36 SS37 33 33 0 0 56 35 56 2-2-13(15) 15-22-31(53) 9-15-13(28) 10-14-28(42) 34-45- 50/4" 8-11-50/5" 47-50/3" OL CL GP 1.0 3.0 25.8 0 TO 1 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 1 TO 3 FEET: SANDY LEAN CLAY; (CL); dark brown to brown; moist; medium plasticity; soft to medium stiff; approximately 30 percent fine to coarse grain sand; approximately 70 percent clayey fines. 3 TO 25.75 FEET: POORLY GRADED GRAVEL WITH SAND ANDCOBBLES; (GP); grayish brown to brown; moist to wet; medium dense to very dense; approximately 60 percent subrounded gravels; approximately 30 percent fine to coarse grain sand; approximately 10 percent clayey fines. Bottom of borehole at 25.8 feet. NOTES Driller: Larry P. / Mike H., Partly Cloudy, Breezy, 20F GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. DRILLING METHOD B-60X Mobile Drill Rig DRILLING CONTRACTOR O'keefe Drilling GROUND WATER LEVELS: DATE STARTED 1/9/25 COMPLETED 1/9/25 AT TIME OF DRILLING 7.50 ft AFTER DRILLING --- AT END OF DRILLING ---DEPTH(ft)0 5 10 15 20 25 SAMPLE TYPENUMBERPAGE 1 OF 1 BORING NUMBER B5 PROJECT NUMBER 25000076.00 CLIENT Rocky Mountain Flats, LLLP PROJECT LOCATION 5532 Fowler Lane, Bozeman MT PROJECT NAME Geotechnical Investigation GENERAL BH / TP / WELL - GINT STD US.GDT - 1/28/25 14:49 - \\FILES\ACTIVE\PROJECTS\2025\25000076.00\DESIGN\CIVIL\GEOTECHNICAL\BORING LOGS\BORING LOGS (25000076.00).GPJRECOVERY %BLOWCOUNTS(N VALUE)U.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION SS38 SS39 SS40 SS41 33 39 39 50 1-4-3(7) 7-21-30(51) 28-47-29(76) 10-12-22(34) OL CL GP 0.5 2.0 9.0 0 TO 0.5 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 0.5 TO 2 FEET: SANDY LEAN CLAY; (CL); dark brown to brown; moist; medium plasticity; soft to medium stiff; approximately 30 percent fine to coarse grain sand; approximately 70 percent clayey fines. 2 TO 9 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); grayish brown to brown; moist to wet; dense to very dense; approximately 60 percent subrounded gravels; approximately 30 percent fine to coarse grain sand; approximately 10 percent clayey fines. Bottom of borehole at 9.0 feet. NOTES Driller: Larry P. / Mike H., Partly Cloudy, Breezy, 20F GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. DRILLING METHOD B-60X Mobile Drill Rig DRILLING CONTRACTOR O'keefe Drilling GROUND WATER LEVELS: DATE STARTED 1/9/25 COMPLETED 1/9/25 AT TIME OF DRILLING 7.50 ft AFTER DRILLING --- AT END OF DRILLING ---DEPTH(ft)0.0 2.5 5.0 7.5 SAMPLE TYPENUMBERPAGE 1 OF 1 BORING NUMBER B6 PROJECT NUMBER 25000076.00 CLIENT Rocky Mountain Flats, LLLP PROJECT LOCATION 5532 Fowler Lane, Bozeman MT PROJECT NAME Geotechnical Investigation GENERAL BH / TP / WELL - GINT STD US.GDT - 1/28/25 14:49 - \\FILES\ACTIVE\PROJECTS\2025\25000076.00\DESIGN\CIVIL\GEOTECHNICAL\BORING LOGS\BORING LOGS (25000076.00).GPJRECOVERY %BLOWCOUNTS(N VALUE)U.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION SS 45 SS47 SS48 SS49 SS49A 51 0 40 0 0 47-50/6" 30-32-27(59) 21-48-50/3" 50/3" 50/3" MC = 4% Fines = 13% OL CL GP 1.0 2.0 25.3 0 TO 1 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 1 TO 2 FEET: SANDY LEAN CLAY; (CL); dark brown to brown; moist; medium plasticity; soft to medium stiff; approximately 30 percent fine to coarse grain sand; approximately 70 percentclayey fines. 2 TO 25.25 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); grayish brown to brown; moist to wet; dense to very dense; approximately 60 percent subrounded gravels; approximately 30 percent fine to coarse grain sand;approximately 10 percent clayey fines. 20: NOTE: at approx. 4' bgs refusal on cobble/boulder, pulled auger to offset 4' and re-drilled boring. Bottom of borehole at 25.3 feet. NOTES Driller: Larry P. / Mike H., Partly Cloudy, Breezy, 20F GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. DRILLING METHOD B-60X Mobile Drill Rig DRILLING CONTRACTOR O'keefe Drilling GROUND WATER LEVELS: DATE STARTED 1/9/25 COMPLETED 1/9/25 AT TIME OF DRILLING 7.50 ft AFTER DRILLING --- AT END OF DRILLING ---DEPTH(ft)0 5 10 15 20 25 SAMPLE TYPENUMBERPAGE 1 OF 1 BORING NUMBER B7 PROJECT NUMBER 25000076.00 CLIENT Rocky Mountain Flats, LLLP PROJECT LOCATION 5532 Fowler Lane, Bozeman MT PROJECT NAME Geotechnical Investigation GENERAL BH / TP / WELL - GINT STD US.GDT - 1/28/25 14:49 - \\FILES\ACTIVE\PROJECTS\2025\25000076.00\DESIGN\CIVIL\GEOTECHNICAL\BORING LOGS\BORING LOGS (25000076.00).GPJRECOVERY %BLOWCOUNTS(N VALUE)TESTS U.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION SS50 SS51 SS52 SS53 17 50 61 50 3-3-3(6) 18-37-40(77) 25-44-50(94) 31-36-43(79) MC = 3%Fines = 12% OL CL GP 0.7 2.0 9.0 0 TO 0.67 FEET: SILTY CLAY ORGANIC SOIL; (OL); dark brown to black; moist; soft. 0.67 TO 2 FEET: SANDY LEAN CLAY; (CL); dark brown to brown; moist; medium plasticity; soft to medium stiff; approximately 30 percent fine to coarse grain sand; approximately 70 percent clayey fines. 2 TO 9 FEET: POORLY GRADED GRAVEL WITH SAND AND COBBLES; (GP); grayish brown to brown; moist to wet; dense to very dense; approximately 60 percent subrounded gravels; approximately 30 percent fine to coarse grain sand;approximately 10 percent clayey fines. Bottom of borehole at 9.0 feet. NOTES Driller: Larry P. / Mike H., Partly Cloudy, Breezy, 20F GROUND ELEVATION LOGGED BY Noah J. Schaible, E.I. DRILLING METHOD B-60X Mobile Drill Rig DRILLING CONTRACTOR O'keefe Drilling GROUND WATER LEVELS: DATE STARTED 1/10/25 COMPLETED 1/10/25 AT TIME OF DRILLING 7.50 ft AFTER DRILLING --- AT END OF DRILLING ---DEPTH(ft)0.0 2.5 5.0 7.5 SAMPLE TYPENUMBERPAGE 1 OF 1 BORING NUMBER B8 PROJECT NUMBER 25000076.00 CLIENT Rocky Mountain Flats, LLLP PROJECT LOCATION 5532 Fowler Lane, Bozeman MT PROJECT NAME Geotechnical Investigation GENERAL BH / TP / WELL - GINT STD US.GDT - 1/28/25 14:49 - \\FILES\ACTIVE\PROJECTS\2025\25000076.00\DESIGN\CIVIL\GEOTECHNICAL\BORING LOGS\BORING LOGS (25000076.00).GPJRECOVERY %BLOWCOUNTS(N VALUE)TESTS U.S.C.S.GRAPHICLOGMATERIAL DESCRIPTION Project Engineer: Noah J. SchaibleProject:Well Information:bgs = below ground surface ags = above ground surfaceMW-1 MW-2 MW-3 MW-4 MW-5 MW-6 MW-73.67 3.25 3.75 2.42 2.42 2.58 3.42Date Depth to Ground Water (feet-bgs)MW-1 MW-2 MW-3 MW-4 MW-5 MW-6 MW-704/07/22 4.62 4.92 4.67 4.70 5.55 5.24 5.1704/15/22 4.98 5.30 5.01 5.04 5.83 5.56 5.4804/21/22 4.93 5.31 5.05 5.10 5.87 5.60 4.7704/29/22 4.26 4.53 4.04 4.24 5.09 4.73 4.8205/06/22 3.66 3.80 3.30 3.28 4.18 4.00 4.2105/13/22 3.41 3.43 2.78 2.70 3.70 3.59 3.9105/20/22 3.28 3.71 3.26 3.17 4.24 4.00 3.9805/27/22 3.20 3.72 3.34 3.30 4.41 4.07 4.4106/03/22 2.94 3.14 2.53 2.42 3.53 3.33 3.5106/10/22 3.38 3.63 2.71 2.56 3.72 3.56 3.9106/17/22 3.43 3.58 3.09 2.89 4.14 3.91 4.1106/24/22 3.62 3.96 3.63 3.54 4.71 4.39 4.3906/30/22 3.63 4.13 3.95 3.92 5.09 4.57 4.4207/08/22 3.72 4.32 4.27 4.31 5.39 4.80 4.5207/15/22 3.71 4.46 4.49 4.64 5.57 4.95 4.5407/22/22 3.75 4.56 4.69 4.90 5.78 5.12 4.6307/29/22 4.00 4.83 4.99 5.21 6.06 5.41 4.8708/05/22 4.31 5.15 5.28 5.49 6.33 5.70 5.1308/12/22 3.74 4.83 5.08 5.34 6.15 5.44 4.7008/19/22 4.20 5.10 5.26 5.49 6.31 5.67 5.0908/26/22 4.14 5.16 5.31 5.54 6.35 5.71 5.05Groundwater Information:N2S2SW4SW4 Sec. 23Monitor Well DataProject Number: 2114315532 Fowler Lane Gallatin County MTProject Location:1143 Stoneridge Drive • Bozeman, Montana • Phone (406) 587-1115Well IDGround Elevation Well Depth (feet bgs)Top of Well (feet ags) Appendix E Stormwater O&M Plan Rocky Mountain Flats – Stormwater Facilities Operation & Maintenance Plan November 13, 2025 Page 1 STORMWATER FACILITIES OPERATION & MAINTENANCE PLAN FOR: Rocky Mountain Flats PROPERTY DESCRIPTION 5532 Fowler Lane Bozeman, MT 59715 N ½ S ½ SW ¼ SW ¼ of Sec. 23 T2S, R5E, PMM, City of Bozeman, MT RESPONSIBLE PARTY Rocky Mountain Flats, LLLP 2432 Kemp Street, Missoula, MT 59801 (406) 214-2052 STORMWATER FACILITIES DESCRIPTION Storm Ponds: The storm ponds for the property were designed to capture runoff from the adjacent street rights-of-way and portions of the apartment site. The ponds were designed with 4:1 max. side slopes. Pond dimensions and depths vary by pond. Refer to the site exhibit in Attachment B for reference. The ponds should be finish graded with 6” of topsoil and fully vegetated with grass per the approved landscape plans. Storm Chases: 18” wide concrete storm chases are designed on Meah Lane and Gabriel Avenue to convey runoff from these streets to retention ponds in locations where insufficient cover exists to install storm inlets with pipes. The chases should be installed per City of Bozeman Standard Drawing No. 02720-11A with a 6” minimum channel depth. Storm Sewer Network: The on-site storm sewer network is comprised of pre-cast concrete curb inlets and manholes, ADS Nyloplast drain basins and inline drains, and ADS HP storm pipe that conveys runoff to the storm chamber systems. The storm sewer network for the public street rights-of-way is also comprised of pre-cast concrete inlets and manholes, but the storm sewer piping for these systems is either SDR-35 PVC pipe or RCP pipe, per city standards. Infiltration Chamber Systems: The proposed stormwater retention chamber systems for the project are ADS Stormtech SC-160LP Chamber Systems. These systems are detailed in the site exhibit in Attachment B and are generally comprised of open-bottomed plastic arches surrounded with washed angular stone to provide storage and infiltration of runoff. Runoff enters each system through a manhole with an internal weir that directs initial runoff to the isolator row of the system. This row is lined with a woven geotextile fabric and an inspection port for easy cleaning of accumulated debris and sediment. On the other side of the weir is the invert to the pipe Manifold that distributes remaining runoff into the rest of the chamber system. The ADS Isolator Row O&M Manual is included with this plan in Attachment C for reference. Rocky Mountain Flats – Stormwater Facilities Operation & Maintenance Plan November 13, 2025 Page 2 INSPECTION & MAINTENANCE SCHEDULE The stormwater facilities on site will be inspected and maintained based on the below schedule. Inspection and maintenance will be performed by the responsible party, the facility employees, or a contracted third party. Inspection: Routine inspection of stormwater facilities will include visual inspection to ensure the facilities are functioning properly and there is no debris accumulated in or clogging the stormwater facilities. Inspections should also be performed after major storm events producing approximately 0.5” of rainfall in a 24-hour period. These inspections shall include observations of the stormwater facilities for areas of erosion or areas of ponding, and removal of accumulated trash or debris in facilities. Maintenance: Maintenance shall be performed as necessary based on inspections, and at regular intervals throughout the year based on the schedule below. Routine Maintenance will generally include removal of trash, overgrown vegetation, grass clippings, leaves, accumulated sediment, and obstructions in stormwater facilities. Major maintenance will be scheduled as necessary to repair or replace damaged storm structures and to revegetate areas of erosion or dead vegetation. Inspection & Maintenance Schedule BMP Inspection Frequency A=Annual, M=Monthly, S=After Major Storm, Q=Quarterly, SA=Semi Annually Maintenance Frequency Catch Basin / Storm Inlet Q 1 / year Swale M 2-3 / year Storm Chase Q 2-3 / year Storm Pond M 3-4 / year Wet Pond Q 2-3 / year Dry Well A 1 / year Underground Storage System SA 1 / year Infiltration Trenches A, S 2-3 / year Table Source: Stormwater Equipment Manufacturers Association Shallow Storm Pond Maintenance: Due to existing site constraints, Storm Ponds #2-1, #2-2, #6, and #9 are designed to be close to the seasonal high groundwater table. Therefore, during the spring there is potential for the soil on the bottoms of these ponds to be saturated with groundwater. Similarly, there is potential for occasional standing water in these ponds during high groundwater years. Maintenance of these facilities should be scheduled during late summer and early fall, when groundwater levels are typically at their lowest, to prevent damage to the facilities. Mowing of these facilities is recommended to take place with a push mower or hand- held trimmer to avoid heavy equipment from rutting the bottom of these facilities. Removal of sediment and debris from these facilities should take place with hand tools or with a vacuum truck parked adjacent to the facility. Rocky Mountain Flats – Stormwater Facilities Operation & Maintenance Plan Page 3 May 26, 2025 ATTACHMENT A Acknowledgement of Stormwater Facility Maintenance Requirements ACKNOWLEDGEMENT OF STORMWATER FACILITIES MAINTENANCE REQUIREMENTS PROJECT NAME: Rocky Mountain Flats CITY OF BOZEMAN PLANNING APPLICATION NUMBER: 24717 DATE: May 26, 2025 PROPERTY OWNER: Rocky Mountain Flats, LLP NAME OF PLAN/DEVELOPMENT: Rocky Mountain Flats LOT/BLOCK/SUBDIVISION: N ½ S ½ SW ¼ SW ¼ of Sec. 23, T2S, R5E, PMM, City of Bozeman, MT Property Owner hereby acknowledges that they are required to maintain all stormwater faciliƟes on the Property pursuant to Bozeman Municipal Code sec. 40.04.720. This requirement is binding on any successor or assign of the Property Owner listed above. The City requires stormwater faciliƟes be constructed and adequately maintained on the Property in order to maintain the health, safety and welfare of City residents. Adequate maintenance is deﬁned as keeping the stormwater faciliƟes and all components thereof in good working condiƟon so that these stormwater faciliƟes conƟnue to perform in accordance with the design intent. Should the Property Owner fail to adequately maintain stormwater faciliƟes, the City may enter upon the Property and take such steps as are necessary to correct deﬁciencies. The City may assess against the Property Owner for the cost of any repairs or necessary maintenance by any means provided for in the Bozeman Municipal Code. By signing below Property Owner acknowledges they have read this document and the applicable provisions of the Bozeman Municipal Code, and they agree to the maintenance requirements for all stormwater faciliƟes on their property. Signature: ______________________________ Date: __________________ By: _________________, __________________________ Rocky Mountain Flats – Stormwater Facilities Operation & Maintenance Plan Page 4 May 26, 2025 ATTACHMENT B Stormwater Facility Exhibit XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXOHPOHPOHPOHPOHPT OHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHPOHP16''W8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W6''W8''W8''SS8''SS8''SS6''W 6''W XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXW VW VW VW VHYDHYD15''SS15''SS15''SS15''SS15''SS15''SS15''SS15''SSGASGASUGPUGPUGPUGPUGPUGPUGPUGPUGP UGP UGP UGP UGP UGP UGP UGP UGP UGP UGPUGPUGPUGPUGPUGP STSTSTELECELECELECELECELECELECELECELECELECELECGASGASGASGASGASGASGASGASGASGASELECELECELECELEC ELEC ELEC STST STSTSTSTSTSTSTSTSTSTST CO CO DSDSDS DS DS DS DS D S DS DS D S DS DS DS ST ST ST ST ST ST ST STSTSTSTSTSTST STSTSTSTSTSTSTSTSTELECELECELECELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC 8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W16''W16''W16''W16''W16''W16''W16''W16''W16''W16''W16''WW V W V W VW V SSW VHY DHY DHYDW VW V SS ST ST ST ST ST STSTST ST STS T STS T ST ST8''SS 8''SS W V FW V 8''SS ST 15''SS15''SS15''SS15''SS15''SS15''SS15''SS15''SS15''SSW BO GASGASGASGASGASGASGASGASGASGASGASGASGASGASGASOSW WBO WBO W VW VELEC ELEC ELEC ELECWBO EDGERTON BLVDFOWLER LANEF.F.E.:5013.40 BLDG A F.F.E.: 5012.80 MEAH LANE MATCH LINEMATCH LINEST 1C-1 (PC) (48") (CURB INLET) TBC: 5011.04 RIM: 5010.53 INV IN: 5008.23 (8")(N) INV IN: 5008.13 (12")(W) INV OUT: 5008.13 (12")(S) ST 1A-7 (DB) (24"∅) RIM:5011.77 INV IN:5008.72 (6")(W) INV IN:5008.52 (8")(E) INV OUT:5008.42 (8")(S) ST 1C-2 (PC) (48"∅) (SOLID COVER) RIM:5010.67 INV IN:5008.08 (12")(N) INV OUT:5008.08 (8")(E) INV OUT:5008.08 (12")(S) ST 1A-5 (ID) (15"∅) RIM:5011.35 INV OUT:5009.00 (6")(SE) ST 1A-4 (DB) (24"∅) RIM:5011.98 INV IN:5008.45 (10")(S) INV IN:5008.68 (8")(N) INV IN:5008.85 (6")(NW) INV OUT:5008.35 (12")(E) ST 1A-3 (ID) (15"∅) RIM:5011.80 INV IN:5008.80 (10")(S) INV OUT:5008.80 (10")(N) ST 1A-2 (DB) (24"∅) RIM:5011.80 INV IN:5009.23 (6")(S) INV OUT:5009.03 (10")(N) ST 1A-1 (ID) (15"∅) RIM:5011.60 INV OUT:5009.45 (6")(N) ST 1B-7 (ID) (24"∅) RIM:5011.92 INV OUT:5009.17 (8")(E) ST 1B-4 (DB) (24"∅) RIM:5012.10 INV IN:5008.75 (8")(W) INV IN:5008.75 (8")(N) INV OUT:5008.59 (10")(S) ST 1B-2 (DB) (24"∅) RIM:5011.73 INV IN:5008.62 (8")(S) INV IN:5008.42 (10")(N) INV IN:5008.82 (6")(NE) INV OUT:5008.32 (12")(W) ST 1D-1 (PC) (48") (CURB INLET) TBC: 5011.06 RIM: 5010.55 INV IN: 5008.16 (12")(E) INV OUT: 5008.16 (12")(SW) ST 1D-2 (PC) (48"∅) (SOLID COVER) RIM:5010.67 INV IN:5008.08 (12")(NE) INV IN:5008.08 (8")(W) INV IN:5008.08 (12")(S) ST 1B-1 (ID) (15"∅) RIM:5011.70 INV OUT:5009.10 (8")(N) STORMTECH SYSTEM #1 MODEL: SC160LP BOTTOM OF SYSTEM STONE: 5007.50 SHGW: 5005.50 STORM FACILITY #6 (RETENTION POND) TOP DIMENSIONS: 230' x 13' 4:1 SIDE SLOPES ELEVATIONS: 5005.40 (TOP) 5003.90 (BOTTOM) SHGW ELEV: 5003.50 REFER TO APPROVED INFRASTRUCTURE PLANS FOR DETAILS STORMTECH SYSTEM #5 MODEL: SC160LP BOTTOM OF SYSTEM STONE: 5007.90 SHGW: 5005.90 REFER TO APPROVED INFRASTRUCTURE PLANS FOR DETAILS ST 5-1 (PC) (36"x24") (CURB INLET) TBC: 5012.94 RIM: 5012.43 INV OUT: 5009.40 (12")(N) ST 4-2 (PC) (48') (CURB INLET) TBC: 5012.67 RIM: 5012.16 INV IN: 5007.98 (18")(S) INV OUT: 5007.88 (18")(N) ST 5-3 (PC) (48"∅) (SOLID COVER) RIM:5011.35 INV IN:5008.48 (15")(SE) INV OUT:5008.48 (8")(W) INV OUT:5008.48 (8")(N) ST 5-4 (PC) (48"∅) (SOLID COVER) RIM:5011.26 INV OUT:5008.48 (8")(E) ST 6-1 (PC) (36"x24") (CURB INLET) TBC: 5008.42 RIM: 5007.91 INV OUT: 5005.30 (12")(W) ST 6-3 (PC) (48"∅) (SOLID COVER) RIM:5008.03 INV IN:5004.60 (15")(SE) INV OUT:5004.50 (15")(W) ST 4-1 (PC) (48"∅) RIM:5007.55 INV IN:5002.92 (18")(S) INV OUT:5002.82 (18")(N) ST 5-2 (PC) (48"∅) (CURB INLET) RIM:5012.43 INV IN:5009.25 (12")(S) INV OUT:5009.08 (15")(NW) ST 1B-3 (ID) (15"∅) RIM:5011.50 INV OUT:5008.95 (6")(SW) ST 6-2 (PC) (48") (CURB INLET) TBC: 5008.38 RIM: 5007.87 INV IN: 5005.14 (12")(E) INV OUT: 5004.89 (15")(NW) STORM SYSTEM #4 (LID POND) TOP DIMENSIONS: 53' x 18' 4:1 SIDE SLOPES ELEVATIONS: 5007.20 (TOP) 5005.70 (BOTTOM) SHGW ELEV: 5003.50 ST 1A-8 (ID) (15"∅) RIM:5011.60 INV OUT:5008.95 (6")(E) 19' of 6" HP PIPE @ 1.18% 55' of 8" HP PIPE @ 0.70% ST 1A-9 (ID) (15"∅) RIM:5011.60 INV OUT:5008.91 (8")(W) ST 1B-6 (ID) (24"∅) RIM:5012.14 INV IN:5008.90 (8")(W) INV OUT:5008.90 (8")(E) 21' of 8" HP PIPE @ 0.70% 8' of 8" HP PIPE @ 1.91% ST 1B-5 (ID) (15"∅) RIM:5012.39 INV OUT:5008.90 (8")(S) 38' of 8" HP PIPE @ 0.70% 28' of 10" HP PIPE @ 0.60% 28' of 12" HP PIPE @ 0.59% 13' of 6" HP PIPE @ 1.03% 7' of 12" HP PIPE @ 1.16% 70' of 8" HP PIPE @ 0.69% 23' of 6" HP PIPE @ 0.96% 39' of 10" HP PIPE @ 0.60% 59' of 10" HP PIPE @ 0.60% 13' of 6" HP PIPE @ 1.14% 43' of 8" HP PIPE @ 0.70% 36' of 12" HP PIPE @ 0.61% 28' of 8" HP PIPE @ 0.70% 6' of 12" HP PIPE @ 0.87% 33' of 12" RCP PIPE @ 0.47% 114' of 15" RCP PIPE @ 0.53% 33' of 12" RCP PIPE @ 0.50% 58' of 15" SDR 35 @ 0.50% 116' of 15" RCP PIPE @ 0.52% 8' of 18" SDR 35 @ 1.60% 311' of 18" SDR 35 @ 1.59% 13' of 18" SDR 35 @ 1.54% INSTALL FES INV OUT:5003.90 INSTALL CAP INV OUT:5008.18 ST 1A-6 (ID) (15"∅) RIM:5012.45 INV OUT:5008.99 (8")(S) F1 STORM FACILITIES - WEST 749-01Alpine Job #: THIS SHEET IS INTENDED TO BE PRINTED IN COLOR TO FULLY UNDERSTAND THE INFORMATION BEING PRESENTED. 2025 ENCOMPASS DESIGN INC.C AN AFFORDABLE HOUSING DEVELOPMENT:ROCKY MOUNTAIN FLATSBOZEMAN, MONTANA1535 liberty lane suite 110b missoula, montana 59808 phone: 406.540.4437 24.115edinc Job #: SITE PLAN REVIEW: 05/29/2025 REV. 02: SP RESUBMITTAL #2 20'0 40' SCALE 1" = 20' N STORM STRUCTURE NOTES 1.ABBREVIATIONS IN STORM STRUCTURE LABELS INDICATE THE FOLLOWING TYPES OF STRUCTURES (ID)ADS NYLOPLAST INLINE DRAIN (DB)ADS NYLOPLAST DRAIN BASIN (PC)PRECAST CONCRETE 2.ALL STRUCTURES ARE ASSUMED TO HAVE SLOTTED PEDESTRIAN GRATES UNLESS OTHERWISE INDICATED IN STRUCTURE LABELS 8''W8''W8''W8''W8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W8''SS8''SSXXXXXXX X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X XXXXXXX<><><><><><><>W V HY DUGPUGPUGPUGPUGPUGP UGP UGP UGP UGP UGP UGP UGP UGP UGP UGP UGP UGP UGP UGP UGP UGP UGP UGP UGP UGPUGPUGPUGPUGPUGPUGPELECELECCO ST STSTSTSTSTSTSTST STSTSTST ST DS DSDS DS D S DS DS DS DS DS DS D S DS DS ST ST STST ST ST STST ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SSW VW VW V W V SS SS ST STSTSTSTST ST ST ST ST W V W V 8''SS ELECH YDELEC ELECW VWBO W B OW B OST 3A-8 (DB) (24"∅) RIM:5013.66 INV IN:5010.51 (6")(W) INV IN:5010.41 (8")(E) INV OUT:5010.31 (8")(S) ST 3C-1 (PC) (48") (CURB INLET) TBC: 5013.06 RIM: 5012.55 INV IN: 5009.95 (12")(W) INV IN: 5010.12 (8")(N) INV OUT: 5009.95 (12")(SW) ST 3C-2 (PC) (48"∅) (S0LID COVER) RIM:5012.63 INV IN:5009.88 (12")(NE) INV IN:5009.88 (12")(S) INV IN:5009.88 (8")(E) ST 3A-5 (DB) (24"∅) RIM:5013.59 INV IN:5010.35 (10")(S) INV IN:5010.51 (8")(N) INV IN:5010.70 (6")(NW) INV OUT:5010.18 (12")(E) ST 3A-7 (ID) (15"∅) RIM:5013.50 INV OUT:5010.82 (8")(S) ST 3A-6 (ID) (15"∅) RIM:5013.40 INV OUT:5010.90 (6")(SE) ST 3A-4 (ID) (15"∅) RIM:5013.50 INV IN:5010.70 (10")(S) INV OUT:5010.70 (10")(N) ST 3A-2 (DB) (24"∅) RIM:5013.61 INV IN:5011.30 (6")(SW) INV IN:5010.99 (10")(N) ST 3A-1 (ID) (15"∅) RIM:5013.40 INV OUT:5011.60 (6")(NE) ST 3B-9 (ID) (15"∅) RIM:5013.78 INV OUT:5010.98 (8")(E) ST 3B-6 (DB) (24"∅) RIM:5013.85 INV IN:5010.57 (8")(W) INV IN:5010.57 (8")(N) INV OUT:5010.48 (10")(S) ST 3B-5 (ID) (15"∅) RIM:5013.20 INV OUT:5010.77 (6")(SW) ST 3B-4 (DB) (24"∅) RIM:5013.41 INV IN:5010.48 (8")(S) INV IN:5010.32 (10")(N) INV IN:5010.65 (6")(NE) INV OUT:5010.15 (12")(W) ST 3D-1 (PC) (48") (CURB INLET) TBC: 5013.61 RIM: 5013.10 INV IN: 5009.95 (12")(E) INV OUT: 5009.95 (12")(W) ST 3D-2 (PC) (48"∅) (SOLID COVER) RIM:5012.56 INV IN:5009.88 (12")(E) INV OUT:5009.88 (12")(S) INV OUT:5009.88 (8")(W) ST 3B-3 (ID) (15"∅) RIM:5013.60 INV IN:5010.77 (8")(S) INV OUT:5010.77 (8")(N) ST 3B-2 (DB) (24"∅) RIM:5013.60 INV IN:5011.10 (6")(SE) INV OUT:5010.94 (8")(N) ST 3B-1 (ID) (15"∅) RIM:5013.60 INV OUT:5011.22 (6")(NW) OVERFLOW RETENTION POND #2-2 4:1 SIDE SLOPES TOP: 5006.50 BOTTOM: 5005.00 GW: 5004.90 STORMTECH SYSTEM #3 MODEL: SC160LP BOTTOM OF STONE: 5009.30 SHGW: 5007.30 GABRIEL AVEMEAH LANE BLDG C F.F.E.:5014.60 43' of 8" HP PIPE @ 0.70% 11' of 6" HP PIPE @ 1.81% 37' of 12" HP PIPE @ 0.62% 27' of 8" HP PIPE @ 0.70% 7' of 12" HP PIPE @ 1.04% 59' of 10" HP PIPE @ 0.60% 23' of 10" HP PIPE @ 0.60% 24' of 6" HP PIPE @ 1.24% 19' of 8" HP PIPE @ 0.70% 27' of 10" HP PIPE @ 0.60% 12' of 6" HP PIPE @ 1.04% 29' of 12" HP PIPE @ 0.69% 7' of 12" HP PIPE @ 1.00% 41' of 8" HP PIPE @ 0.70% 24' of 8" HP PIPE @ 0.70% 12' of 6" HP PIPE @ 1.00%MATCH LINE12" CULVERT TO HYDRAULICALLY CONNECT PONDS MATCH LINEST 8-2 (PC) (48"∅) (SOLID COVER) RIM:5013.66 INV IN:5010.28 (12")(SE) INV OUT:5010.28 (8")(W) INV OUT:5010.28 (8")(N) ST 8-1 (PC) (48") (CURB INLET) TBC: 5013.92 RIM: 5013.41 INV OUT: 5010.83 (12")(NW) ST 8-3 (PC) (48"∅) (S0LID COVER) RIM:5013.40 INV OUT:5010.28 (8")(E) ST 9-1 (PC) (36"x24") (CURB INLET) TBC: 5010.71 RIM: 5010.20 INV OUT: 5007.70 (12")(E) ST 9-2 (PC) (48") (CURB INLET) TBC: 5010.71 RIM: 5010.20 INV IN: 5007.53 (12")(W) INV OUT: 5007.33 (15")(N) 107' of 12" SDR 35 @ 0.52% 33' of 12" SDR 35 @ 0.50% 92' of 15" SDR 35 @ 0.52% STORMTECH SYSTEM #8 MODEL: SC160LP BOTTOM OF STONE: 5009.70 SHGW: 5007.65 REFER TO APPROVED INFRASTRUCTURE PLANS FOR DETAILS 18" WIDE STORM CHASE. REFER TO APPROVED INFRASTRUCTURE PLANS FOR DETAILS 18" WIDE STORM CHASE. REFER TO APPROVED INFRASTRUCTURE PLANS FOR DETAILS INSTALL FES INV OUT:5006.85 OVERFLOW RETENTION POND #2-1 4:1 SIDE SLOPES TOP: 5006.50 BOTTOM: 5004.50 GW: 5004.25 STORM SYSTEM #9 (RETENTION POND) 4:1 SIDE SLOPES TOP: 5008.00 BOTTOM: 5006.80 GW: 5006.60 REFER TO APPROVED INFRASTRUCTURE PLANS FOR DETAILS STORM SYSTEM #8 (RETENTION POND) 4:1 SIDE SLOPES TOP: 5013.00 BOTTOM: 5012.10 GW: 50010.10 REFER TO APPROVED INFRASTRUCTURE PLANS FOR DETAILS REFER TO APPROVED INFRASTRUCTURE PLAN SET FOR BOULEVARD SWALE DETAILS ST 3A-9 (ID) (15"∅) RIM:5014.00 INV OUT:5010.72 (6")(E)21' of 6" HP PIPE @ 1.00% 54' of 8" HP PIPE @ 0.70% ST 3A-10 (15"∅) RIM:5013.69 INV OUT:5010.79 (8")(W) ST 3B-8 (ID) (15"∅) RIM:5014.03 INV IN:5010.70 (8")(W) INV OUT:5010.70 (8")(E)8' of 8" HP PIPE @ 0.70%ST 3B-7 (ID) (15"∅) RIM:5014.20 INV OUT:5010.62 (8")(S) ST 3A-3 (ID) (15"∅) RIM:5014.52 INV OUT:5010.84 (10")(S) INV OUT:5010.84 (10")(N) 25' of 10" HP PIPE @ -0.60% F2 STORM FACILITIES - CENTER 749-01Alpine Job #: THIS SHEET IS INTENDED TO BE PRINTED IN COLOR TO FULLY UNDERSTAND THE INFORMATION BEING PRESENTED. 2025 ENCOMPASS DESIGN INC.C AN AFFORDABLE HOUSING DEVELOPMENT:ROCKY MOUNTAIN FLATSBOZEMAN, MONTANA1535 liberty lane suite 110b missoula, montana 59808 phone: 406.540.4437 24.115edinc Job #: SITE PLAN REVIEW: 05/29/2025 REV. 02: SP RESUBMITTAL #2 20'0 40' SCALE 1" = 20' N STORM STRUCTURE NOTES 1.ABBREVIATIONS IN STORM STRUCTURE LABELS INDICATE THE FOLLOWING TYPES OF STRUCTURES (ID)ADS NYLOPLAST INLINE DRAIN (DB)ADS NYLOPLAST DRAIN BASIN (PC)PRECAST CONCRETE 2.ALL STRUCTURES ARE ASSUMED TO HAVE SLOTTED PEDESTRIAN GRATES UNLESS OTHERWISE INDICATED IN STRUCTURE LABELS 8''W 8''W 8''W 8''W 8''W 8''W6''W8''W8''W8''SS8''SS8''SS8''SSX X X X X X X X X X X X X X X X XXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXW VW VHYDGASGASUGPUGPUGPUGPUGPUGPUGPUGPELECELECELECELECELECELECELECELECELECELECGASGASGASGASGASGASGASGASGASGASELECELECELECELEC ELEC ELEC STSTSTSTST STSTSTSTSTSTSTSTSTSTCO CO ST ST ST D S D S DS D S DS D S DS DS DS DS DS DS DS DS DS DS DS ST ST ST STST ST ST ST ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC 8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''WW V W VW V SSHYDHYD HY DW VW VW V SS ST ST ST ST STSTST ST STST STSTSTSTSTSTSTSTSTST8''SS 8''SS W V FW V FW VW V8''SS ELEC ELECWBO WBO W B OWBO ELEC ELEC ELEC ELECWBO EDGERTON BLVDBLDG B F.F.E.:5013.40 MEAH LANE MATCH LINEMATCH LINEMATCH LINEMEAH LANE MATCH LINEST 2A-5 (ID) (15"∅) RIM:5012.77 INV IN:5008.54 (10")(S) INV OUT:5008.54 (10")(N) 19' of 10" HP PIPE @ 0.80% 24' of 8" HP PIPE @ 0.90% ST 2A-2 (ID) (15"∅) RIM:5012.42 INV IN:5009.29 (8")(E) INV OUT:5009.29 (8")(W) 46' of 8" HP PIPE @ 0.90% ST 2A-1 (ID) (15"∅) RIM:5012.81 INV OUT:5009.70 (8")(W) STORMTECH SYSTEM #2-3 MODEL: SC160LP BOTTOM OF SYSTEM STONE: 5009.00 SHGW: 5007.00 STORMTECH SYSTEM #2-1 MODEL: SC160LP BOTTOM OF SYSTEM STONE: 5007.10 SHGW: 5004.8 STORMTECH SYSTEM #2-2 MODEL: SC160LP BOTTOM OF SYSTEM STONE: 5006.10 GW: 5003.90 ST 2D-1 (PC) (48") (CURB INLET) TBC: 5012.66 RIM: 5012.15 INV OUT: 5009.70 (10")(N) ST 2D-2 (PC) (48"∅) (SOLID COVER) RIM:5012.35 INV IN:5009.58 (10")(S) INV OUT:5009.58 (8")(E) INV OUT:5009.58 (8")(N) ST 2A-7 (ID) (15"∅) (SOLID COVER) RIM:5011.15 INV OUT:5008.65 (8")(S) ST 2A-8 (PC) (48"∅) (SOLID COVER) RIM:5010.50 INV IN:5007.68 (12")(W) INV OUT:5007.68 (8")(E) INV OUT:5007.68 (8")(N) ST 2A-9 (PC) (48"∅) (SOLID COVER) RIM:5010.46 INV OUT:5007.68 (8")(W) ST 2C-1 (PC) (48") (CURB INLET) TBC: 5009.61 RIM: 5009.10 INV OUT: 5006.73 (10")(N) ST 2C-2 (PC) (48"∅) (SOLID COVER) RIM:5009.31 INV IN:5006.68 (8")(W) INV IN:5006.68 (10")(S) INV IN:5006.68 (8")(N) ST 2B-2 (PC) (48"∅) (SOLID COVER) RIM:5009.31 INV IN:5006.68 (8")(E) INV IN:5006.68 (10")(SE) INV IN:5006.68 (8")(N)ST 2B-1 (PC) (48") (CURB INLET) TBC: 5009.61 RIM: 5009.10 INV OUT: 5006.73 (10")(NW) ST 2A-6 (DB) (24"∅) RIM:5011.91 INV IN:5008.08 (10")(S) INV IN:5008.25 (8")(N) INV OUT:5007.92 (12")(E) ST 2A-4 (DB) (24"∅) RIM:5012.50 INV IN:5008.87 (8")(SE) INV OUT:5008.70 (10")(N) ST 2A-3 (DB) (24"∅) RIM:5012.50 INV IN:5009.07 (8")(E) INV OUT:5008.97 (8")(NW) 10' of 10" HP PIPE @ 0.50% 11' of 10" HP PIPE @ 0.50% 35' of 12" HP PIPE @ 0.70% 38' of 8" HP PIPE @ 1.03% 57' of 10" HP PIPE @ 0.80% 12' of 8" HP PIPE @ 0.90% 17' of 10" HP PIPE @ 0.70% ST 7-1 (PC) (36"x24") (CURB INLET) TBC: 5012.86 RIM: 5012.35 INV OUT: 5009.20 (12")(N) ST 7-2 (PC) (48") (CURB INLET) TBC: 5012.86 RIM: 5012.35 INV IN: 5009.00 (12")(S) INV OUT: 5008.75 (15")(N) ST 7-4 (PC) (48"∅) (SOLID COVER) RIM:5010.69 INV OUT:5007.68 (8")(W)ST 7-3 (PC) (48"∅) (SOLID COVER) RIM:5010.46 INV IN:5007.68 (15")(S) INV OUT:5007.68 (8")(E) INV OUT:5007.68 (8")(N) 33' of 12" RCP PIPE @ 0.61% 196' of 15" SDR 35 @ 0.54% STORMTECH SYSTEM #2-1 MODEL: SC160LP BOTTOM OF SYSTEM STONE: 5007.10 SHGW: 5005.00 REFER TO APPROVED INFRASTRUCTURE PLANS FOR DETAILS ST 3A-9 (ID) (15"∅) RIM:5014.00 INV OUT:5010.72 (6")(E)21' of 6" HP PIPE @ 1.00% ST 3A-3 (ID) (15"∅) RIM:5014.52 INV OUT:5010.84 (10")(S) INV OUT:5010.84 (10")(N) 25' of 10" HP PIPE @ -0.60% F3 STORM FACILITIES - EAST 749-01Alpine Job #: THIS SHEET IS INTENDED TO BE PRINTED IN COLOR TO FULLY UNDERSTAND THE INFORMATION BEING PRESENTED. 2025 ENCOMPASS DESIGN INC.C AN AFFORDABLE HOUSING DEVELOPMENT:ROCKY MOUNTAIN FLATSBOZEMAN, MONTANA1535 liberty lane suite 110b missoula, montana 59808 phone: 406.540.4437 24.115edinc Job #: SITE PLAN REVIEW: 05/29/2025 REV. 02: SP RESUBMITTAL #2 20'0 40' SCALE 1" = 20' N STORM STRUCTURE NOTES 1.ABBREVIATIONS IN STORM STRUCTURE LABELS INDICATE THE FOLLOWING TYPES OF STRUCTURES (ID)ADS NYLOPLAST INLINE DRAIN (DB)ADS NYLOPLAST DRAIN BASIN (PC)PRECAST CONCRETE 2.ALL STRUCTURES ARE ASSUMED TO HAVE SLOTTED PEDESTRIAN GRATES UNLESS OTHERWISE INDICATED IN STRUCTURE LABELS 749-01Alpine Job #: THIS SHEET IS INTENDED TO BE PRINTED IN COLOR TO FULLY UNDERSTAND THE INFORMATION BEING PRESENTED. 2025 ENCOMPASS DESIGN INC.C AN AFFORDABLE HOUSING DEVELOPMENT:ROCKY MOUNTAIN FLATSBOZEMAN, MONTANA1535 liberty lane suite 110b missoula, montana 59808 phone: 406.540.4437 24.115edinc Job #: SITE PLAN REVIEW: 05/29/2025 REV. 02: SP RESUBMITTAL #2 F4 DETAILS MATERIAL LOCATION DESCRIPTION AASHTO MATERIAL CLASSIFICATIONS COMPACTION / DENSITY REQUIREMENT D FINAL FILL: FILL MATERIAL FOR LAYER 'D' STARTS FROM THE TOP OF THE 'C' LAYER TO THE BOTTOM OF FLEXIBLE PAVEMENT OR UNPAVED FINISHED GRADE ABOVE. NOTE THAT PAVEMENT SUBBASE MAY BE PART OF THE 'D' LAYER ANY SOIL/ROCK MATERIALS, NATIVE SOILS, OR PER ENGINEER'S PLANS. CHECK PLANS FOR PAVEMENT SUBGRADE REQUIREMENTS.N/A PREPARE PER SITE DESIGN ENGINEER'S PLANS. PAVED INSTALLATIONS MAY HAVE STRINGENT MATERIAL AND PREPARATION REQUIREMENTS. C INITIAL FILL: FILL MATERIAL FOR LAYER 'C' STARTS FROM THE TOP OF THE EMBEDMENT STONE ('B' LAYER) TO 14" (355 mm) ABOVE THE TOP OF THE CHAMBER. NOTE THAT PAVEMENT SUBBASE MAY BE A PART OF THE 'C' LAYER. GRANULAR WELL-GRADED SOIL/AGGREGATE MIXTURES, <35% FINES OR PROCESSED AGGREGATE. MOST PAVEMENT SUBBASE MATERIALS CAN BE USED IN LIEU OF THIS LAYER. AASHTO M145¹ A-1, A-2-4, A-3 OR AASHTO M43¹ 3, 357, 4, 467, 5, 56, 57, 6, 67, 68, 7, 78, 8, 89, 9, 10 BEGIN COMPACTIONS AFTER 12" (300 mm) OF MATERIAL OVER THE CHAMBERS IS REACHED. COMPACT ADDITIONAL LAYERS IN 6" (150 mm) MAX LIFTS TO A MIN. 95% PROCTOR DENSITY FOR WELL GRADED MATERIAL AND 95% RELATIVE DENSITY FOR PROCESSED AGGREGATE MATERIALS. ROLLER GROSS VEHICLE WEIGHT NOT TO EXCEED 12,000 lbs (53 kN). DYNAMIC FORCE NOT TO EXCEED 20,000 lbs (89 kN). B EMBEDMENT STONE: FILL SURROUNDING THE CHAMBERS FROM THE FOUNDATION STONE ('A' LAYER) TO THE 'C' LAYER ABOVE.CLEAN, CRUSHED, ANGULAR STONE AASHTO M43¹ 3, 357, 4, 467, 5, 56, 57 NO COMPACTION REQUIRED. A FOUNDATION STONE: FILL BELOW CHAMBERS FROM THE SUBGRADE UP TO THE FOOT (BOTTOM) OF THE CHAMBER.CLEAN, CRUSHED, ANGULAR STONE AASHTO M43¹ 3, 357, 4, 467, 5, 56, 57 PLATE COMPACT OR ROLL TO ACHIEVE A FLAT SURFACE.2,3 PLEASE NOTE: 1.THE LISTED AASHTO DESIGNATIONS ARE FOR GRADATIONS ONLY. THE STONE MUST ALSO BE CLEAN, CRUSHED, ANGULAR. FOR EXAMPLE, A SPECIFICATION FOR #4 STONE WOULD STATE: "CLEAN, CRUSHED, ANGULAR NO. 4 (AASHTO M43) STONE". 2.STORMTECH COMPACTION REQUIREMENTS ARE MET FOR 'A' LOCATION MATERIALS WHEN PLACED AND COMPACTED IN 6" (150 mm) (MAX) LIFTS USING TWO FULL COVERAGES WITH A VIBRATORY COMPACTOR. 3.WHERE INFILTRATION SURFACES MAY BE COMPROMISED BY COMPACTION, FOR STANDARD DESIGN LOAD CONDITIONS, A FLAT SURFACE MAY BE ACHIEVED BY RAKING OR DRAGGING WITHOUT COMPACTION EQUIPMENT. FOR SPECIAL LOAD DESIGNS, CONTACT STORMTECH FOR COMPACTION REQUIREMENTS. 4.ONCE LAYER 'C' IS PLACED, ANY SOIL/MATERIAL CAN BE PLACED IN LAYER 'D' UP TO THE FINISHED GRADE. MOST PAVEMENT SUBBASE SOILS CAN BE USED TO REPLACE THE MATERIAL REQUIREMENTS OF LAYER 'C' OR 'D' AT THE SITE DESIGN ENGINEER'S DISCRETION. ACCEPTABLE FILL MATERIALS: STORMTECH SC-160LP CHAMBER SYSTEMS NOTES: 1.CHAMBERS SHALL MEET THE REQUIREMENTS OF ASTM F2418, "STANDARD SPECIFICATION FOR POLYPROPYLENE (PP) CORRUGATED WALL STORMWATER COLLECTION CHAMBERS". 2.CHAMBERS SHALL BE DESIGNED, TESTED AND ALLOWABLE LOAD CONFIGURATIONS DETERMINED IN ACCORDANCE WITH ASTM F2787, "STANDARD PRACTICE FOR STRUCTURAL DESIGN OF THERMOPLASTIC CORRUGATED WALL STORMWATER COLLECTION CHAMBERS". LOAD CONFIGURATIONS SHALL INCLUDE: 1) INSTANTANEOUS (<1 MIN) AASHTO DESIGN TRUCK LIVE LOAD ON MINIMUM COVER 2) MAXIMUM PERMANENT (75-YR) COVER LOAD AND 3) ALLOWABLE COVER WITH PARKED (1-WEEK) AASHTO DESIGN TRUCK. 3.THE SITE DESIGN ENGINEER IS RESPONSIBLE FOR ASSESSING THE BEARING RESISTANCE (ALLOWABLE BEARING CAPACITY) OF THE SUBGRADE SOILS AND THE DEPTH OF FOUNDATION STONE WITH CONSIDERATION FOR THE RANGE OF EXPECTED SOIL MOISTURE CONDITIONS. 4.PERIMETER STONE MUST BE EXTENDED HORIZONTALLY TO THE EXCAVATION WALL FOR BOTH VERTICAL AND SLOPED EXCAVATION WALLS. 5.REQUIREMENTS FOR HANDLING AND INSTALLATION: ·TO MAINTAIN THE WIDTH OF CHAMBERS DURING SHIPPING AND HANDLING, CHAMBERS SHALL HAVE INTEGRAL, INTERLOCKING STACKING LUGS ·TO ENSURE A SECURE JOINT DURING INSTALLATION AND BACKFILL, THE HEIGHT OF THE CHAMBER JOINT SHALL NOT BE LESS THAN 1.5” ·TO ENSURE THE INTEGRITY OF THE ARCH SHAPE DURING INSTALLATION, a) THE ARCH STIFFNESS CONSTANT SHALL BE GREATER THAN OR EQUAL TO 400 LBS/FT/%. THE ASC IS DEFINED IN SECTION 6.2.8 OF ASTM F2418. AND b) TO RESIST CHAMBER DEFORMATION DURING INSTALLATION AT ELEVATED TEMPERATURES (ABOVE 73° F / 23° C), CHAMBERS SHALL BE PRODUCED FROM REFLECTIVE GOLD OR YELLOW COLORS. D C B A 6" N12 8" N12 SC-160StormTech 6" N12 8" N12 SC-160StormTech 6" N12 8" N12 SC-160StormTech 6" N12 8" N12 SC-160StormTech 6" N1 8" N12 SC-160StormTech PAVEMENT LAYER (DESIGNED BY SITE DESIGN ENGINEER) SUBGRADE SOILS (SEE NOTE 3) PERIMETER STONE (SEE NOTE 4) EXCAVATION WALL (CAN BE SLOPED OR VERTICAL) SC-160LP END CAP NO SPACING REQUIRED BETWEEN CHAMBERS 12" (300 mm) 14" (350 mm) MIN* 10' (3.0 m) MAX 6" (150 mm) MIN 12" (300 mm) MIN 25" (635 mm) 12" (300 mm) TYP DEPTH OF BASE STONE TO BE DETERMINED BY SITE DESIGN ENGINEER 6" (150 mm) MIN ADS GEOSYNTHETICS 601T NON-WOVEN GEOTEXTILE ALL AROUND CLEAN, CRUSHED, ANGULAR STONE IN A & B LAYERS SC-160LP ISOLATOR ROW PLUS DETAIL NTS CATCH BASIN OR MANHOLE SC-160LP CHAMBERSTORMTECH HIGHLY RECOMMENDS FLEXSTORM INSERTS IN ANY UPSTREAM STRUCTURES WITH OPEN GRATES 8" (200 mm) HDPE ACCESS PIPE REQUIRED USE 8" OPEN END CAP PART #: SC160IEPP08 SC-160LP END CAP OPTIONAL INSPECTION PORT ONE LAYER OF ADSPLUS125 WOVEN GEOTEXTILE BETWEEN FOUNDATION STONE AND CHAMBERS 4' (1.2 m) MIN WIDE CONTINUOUS FABRIC WITHOUT SEAMS SUMP DEPTH TBD BY SITE DESIGN ENGINEER (24" [600 mm] MIN RECOMMENDED) INSPECTION & MAINTENANCE STEP 1)INSPECT ISOLATOR ROW PLUS FOR SEDIMENT A.INSPECTION PORTS (IF PRESENT) A.1.REMOVE/OPEN LID ON NYLOPLAST INLINE DRAIN A.2.REMOVE AND CLEAN FLEXSTORM FILTER IF INSTALLED A.3.USING A FLASHLIGHT AND STADIA ROD, MEASURE DEPTH OF SEDIMENT AND RECORD ON MAINTENANCE LOG A.4.LOWER A CAMERA INTO ISOLATOR ROW PLUS FOR VISUAL INSPECTION OF SEDIMENT LEVELS (OPTIONAL) A.5.IF SEDIMENT IS AT, OR ABOVE, 3" (80 mm) PROCEED TO STEP 2. IF NOT, PROCEED TO STEP 3. B.ALL ISOLATOR PLUS ROWS B.1.REMOVE COVER FROM STRUCTURE AT UPSTREAM END OF ISOLATOR ROW PLUS B.2.USING A FLASHLIGHT, INSPECT DOWN THE ISOLATOR ROW PLUS THROUGH OUTLET PIPE i)MIRRORS ON POLES OR CAMERAS MAY BE USED TO AVOID A CONFINED SPACE ENTRY ii)FOLLOW OSHA REGULATIONS FOR CONFINED SPACE ENTRY IF ENTERING MANHOLE B.3.IF SEDIMENT IS AT, OR ABOVE, 3" (80 mm) PROCEED TO STEP 2. IF NOT, PROCEED TO STEP 3. STEP 2)CLEAN OUT ISOLATOR ROW PLUS USING THE JETVAC PROCESS A.A FIXED CULVERT CLEANING NOZZLE WITH REAR FACING SPREAD OF 45" (1.1 m) OR MORE IS PREFERRED B.APPLY MULTIPLE PASSES OF JETVAC UNTIL BACKFLUSH WATER IS CLEAN C.VACUUM STRUCTURE SUMP AS REQUIRED STEP 3)REPLACE ALL COVERS, GRATES, FILTERS, AND LIDS; RECORD OBSERVATIONS AND ACTIONS. STEP 4)INSPECT AND CLEAN BASINS AND MANHOLES UPSTREAM OF THE STORMTECH SYSTEM. NOTES 1.INSPECT EVERY 6 MONTHS DURING THE FIRST YEAR OF OPERATION. ADJUST THE INSPECTION INTERVAL BASED ON PREVIOUS OBSERVATIONS OF SEDIMENT ACCUMULATION AND HIGH WATER ELEVATIONS. 2.CONDUCT JETTING AND VACTORING ANNUALLY OR WHEN INSPECTION SHOWS THAT MAINTENANCE IS NECESSARY. SC-160LP 6" INSPECTION PORT DETAIL NTS * THE PART# 2712AG6IPKIT CAN BE USED TO ORDER ALL NECESSARY COMPONENTS FOR A SOLID LID INSPECTION PORT INSTALLATION 6" (150 mm) INSERTA TEE PART# 6P26FBSTIP* INSERTA TEE TO BE CENTERED ON CORRUGATION CREST FLEXSTORM CATCH IT PART# 6212NYFX WITH USE OF OPEN GRATE PAVEMENT CONCRETE COLLAR CONCRETE COLLAR NOT REQUIRED FOR UNPAVED APPLICATION 12" (300 mm) NYLOPLAST INLINE DRAIN BODY W/SOLID HINGED COVER OR GRATE PART# 2712AG6IP* SOLID COVER: 1299CGC* GRATE: 1299CGS 6" (150 mm) SDR35 PIPE SC-160LP CHAMBER 18" (450 mm) MIN WIDTH CONCRETE SLAB 8" (200 mm) MIN THICKNESS PART #STUB A SC160EPP 6" (150 mm)0.66" (16 mm) 8" (200 mm)0.80" (20 mm) SC160EPP08 8" (200 mm)0.96" (24 mm) ALL STUBS ARE PLACED AT BOTTOM OF END CAP SUCH THAT THE OUTSIDE DIAMETER OF THE STUB IS FLUSH WITH THE BOTTOM OF THE END CAP. FOR ADDITIONAL INFORMATION CONTACT STORMTECH AT 1-888-892-2694. NOTE: ALL DIMENSIONS ARE NOMINAL NOMINAL CHAMBER SPECIFICATIONS SIZE (W X H X INSTALLED LENGTH)25.0" X 12.0" X 85.4" (635 mm X 305 mm X 2169 mm) CHAMBER STORAGE 6.85 CUBIC FEET (0.19 m³) MINIMUM INSTALLED STORAGE*16.0 CUBIC FEET (0.45 m³) WEIGHT 24.0 lbs.(10.9 kg) *ASSUMES 6" (152 mm) ABOVE, 6" (152 mm) BELOW, AND STONE BETWEEN CHAMBERS WITH 40% STONE POROSITY. BUILD ROW IN THIS DIRECTION START END SC-160LP TECHNICAL SPECIFICATION NTS SC-160StormTech 6" N12 8" N12 SC-160StormTech OVERLAP NEXT CHAMBER HERE (OVER SMALL CORRUGATION) 25.0" (635 mm) 12.0" (305 mm) 90.7" (2304 mm) ACTUAL LENGTH 85.4" (2169 mm) INSTALLED LENGTH 4.4" (112 mm) A 11.7" (297 mm) 18.6" (472 mm) STORMTECH SC-160 LP PROFILE2SCALE: NTS STORMTECH SC-160 LP PROFILE ISOLATOR ROW & INSPECTION PORT DETAIL1SCALE: NTS STORMTECH SC-160 LP TECHNICAL DETAILS3SCALE: NTS CONCEPTUAL ELEVATIONS MAXIMUM ALLOWABLE GRADE (TOP OF PAVEMENT/UNPAVED):11.50 MINIMUM ALLOWABLE GRADE (UNPAVED WITH TRAFFIC):3.17 MINIMUM ALLOWABLE GRADE (UNPAVED NO TRAFFIC):2.67 MINIMUM ALLOWABLE GRADE (TOP OF RIGID CONCRETE PAVEMENT):2.67 MINIMUM ALLOWABLE GRADE (BASE OF FLEXIBLE PAVEMENT):2.67 TOP OF STONE:2.00 TOP OF SC-160LP CHAMBER:1.50 8" x 8" BOTTOM MANIFOLD INVERT:0.58 8" x 8" BOTTOM MANIFOLD INVERT:0.58 8" ISOLATOR ROW PLUS INVERT:0.58 8" ISOLATOR ROW PLUS INVERT:0.58 BOTTOM OF SC-160LP CHAMBER:0.50 BOTTOM OF STONE:0.00 PROPOSED LAYOUT 144 STORMTECH SC-160LP CHAMBERS 18 STORMTECH SC-160LP END CAPS 6 STONE ABOVE (in) 6 STONE BELOW (in) 40 STONE VOID 2612 INSTALLED SYSTEM VOLUME (CF) (PERIMETER STONE INCLUDED) (COVER STONE INCLUDED) (BASE STONE INCLUDED) 2524 SYSTEM AREA (SF) 288.4 SYSTEM PERIMETER (ft) MAX FLOWINVERT*DESCRIPTIONITEM ON LAYOUTPART TYPE 0.96"8" x 8" BOTTOM MANIFOLD, MOLDED FITTINGSAMANIFOLD 0.96"8" x 8" BOTTOM MANIFOLD, MOLDED FITTINGSBMANIFOLD 2.2 CFS IN(DESIGN BY ENGINEER / PROVIDED BY OTHERS)CCONCRETE STRUCTURE W/WEIR 2.2 CFS IN(DESIGN BY ENGINEER / PROVIDED BY OTHERS)DCONCRETE STRUCTURE W/WEIR ISOLATOR ROW PLUS (SEE DETAIL) PLACE MINIMUM 12.50' OF ADSPLUS625 WOVEN GEOTEXTILE OVER BEDDING STONE AND UNDERNEATH CHAMBER FEET FOR SCOUR PROTECTION AT ALL CHAMBER INLET ROWS BED LIMITS 123.43'20.75'114.33'18.75'NOTES •THE SITE DESIGN ENGINEER MUST REVIEW ELEVATIONS AND IF NECESSARY ADJUST GRADING TO ENSURE THE CHAMBER COVER REQUIREMENTS ARE MET. •NOT FOR CONSTRUCTION: THIS LAYOUT IS FOR DIMENSIONAL PURPOSES ONLY TO PROVE CONCEPT & THE REQUIRED STORAGE VOLUME CAN BE ACHIEVED ON SITE. *INVERT ABOVE BASE OF CHAMBER AB D C STORMTECH SC-160 LP SYSTEM 14SCALE: NTS *TO BOTTOM OF FLEXIBLE PAVEMENT. FOR UNPAVED INSTALLATIONS WHERE RUTTING FROM VEHICLES MAY OCCUR, INCREASE COVER TO 20" (510 mm). Xref ..\..\..\..\..\Standards\Civil 3D\Base Maps\City of Bozeman\Bozeman Vicinity Map 2024.dwg 749-01Alpine Job #: THIS SHEET IS INTENDED TO BE PRINTED IN COLOR TO FULLY UNDERSTAND THE INFORMATION BEING PRESENTED. 2025 ENCOMPASS DESIGN INC.C AN AFFORDABLE HOUSING DEVELOPMENT:ROCKY MOUNTAIN FLATSBOZEMAN, MONTANA1535 liberty lane suite 110b missoula, montana 59808 phone: 406.540.4437 24.115edinc Job #: SITE PLAN REVIEW: 05/29/2025 REV. 02: SP RESUBMITTAL #2 F5 DETAILS ISOLATOR ROW PLUS (SEE DETAIL) PLACE MINIMUM 12.50' OF ADSPLUS625 WOVEN GEOTEXTILE OVER BEDDING STONE AND UNDERNEATH CHAMBER FEET FOR SCOUR PROTECTION AT ALL CHAMBER INLET ROWS BED LIMITS NOTES •THE SITE DESIGN ENGINEER MUST REVIEW ELEVATIONS AND IF NECESSARY ADJUST GRADING TO ENSURE THE CHAMBER COVER REQUIREMENTS ARE MET. •NOT FOR CONSTRUCTION: THIS LAYOUT IS FOR DIMENSIONAL PURPOSES ONLY TO PROVE CONCEPT & THE REQUIRED STORAGE VOLUME CAN BE ACHIEVED ON SITE. STORMTECH SC-160 LP SYSTEM 2-22SCALE: NTS CONCEPTUAL ELEVATIONS MAXIMUM ALLOWABLE GRADE (TOP OF PAVEMENT/UNPAVED):11.50 MINIMUM ALLOWABLE GRADE (UNPAVED WITH TRAFFIC):3.17 MINIMUM ALLOWABLE GRADE (UNPAVED NO TRAFFIC):2.67 MINIMUM ALLOWABLE GRADE (TOP OF RIGID CONCRETE PAVEMENT):2.67 MINIMUM ALLOWABLE GRADE (BASE OF FLEXIBLE PAVEMENT):2.67 TOP OF STONE:2.00 TOP OF SC-160LP CHAMBER:1.50 8" x 8" BOTTOM MANIFOLD INVERT:0.58 8" x 8" BOTTOM MANIFOLD INVERT:0.58 8" ISOLATOR ROW PLUS INVERT:0.58 8" ISOLATOR ROW PLUS INVERT:0.58 BOTTOM OF SC-160LP CHAMBER:0.50 BOTTOM OF STONE:0.00 PROPOSED LAYOUT STORMTECH SC-160LP CHAMBERS STORMTECH SC-160LP END CAPS STONE ABOVE (in) STONE BELOW (in) STONE VOID INSTALLED SYSTEM VOLUME (CF) (PERIMETER STONE INCLUDED) (COVER STONE INCLUDED) (BASE STONE INCLUDED) SYSTEM AREA (SF) SYSTEM PERIMETER (ft) MAX FLOWINVERT*DESCRIPTIONITEM ON LAYOUTPART TYPE 0.96"8" x 8" BOTTOM MANIFOLD, MOLDED FITTINGSAMANIFOLD 0.96"8" x 8" BOTTOM MANIFOLD, MOLDED FITTINGSBMANIFOLD 1.5 CFS IN(DESIGN BY ENGINEER / PROVIDED BY OTHERS)CCONCRETE STRUCTURE W/WEIR 1.5 CFS IN(DESIGN BY ENGINEER / PROVIDED BY OTHERS)DCONCRETE STRUCTURE W/WEIR *INVERT ABOVE BASE OF CHAMBER 94.96'16.58'85.87'14.58'B A D C CONCEPTUAL ELEVATIONS MAXIMUM ALLOWABLE GRADE (TOP OF PAVEMENT/UNPAVED):11.50 MINIMUM ALLOWABLE GRADE (UNPAVED WITH TRAFFIC):3.17 MINIMUM ALLOWABLE GRADE (UNPAVED NO TRAFFIC):2.67 MINIMUM ALLOWABLE GRADE (TOP OF RIGID CONCRETE PAVEMENT):2.67 MINIMUM ALLOWABLE GRADE (BASE OF FLEXIBLE PAVEMENT):2.67 TOP OF STONE:2.00 TOP OF SC-160LP CHAMBER:1.50 8" ISOLATOR ROW PLUS INVERT:0.58 8" ISOLATOR ROW PLUS INVERT:0.58 12" x 8" BOTTOM MANIFOLD INVERT (8" PIPE):0.58 12" x 8" BOTTOM MANIFOLD INVERT (8" PIPE):0.58 BOTTOM OF SC-160LP CHAMBER:0.50 12" x 8" BOTTOM MANIFOLD INVERT (12" PIPE):0.40 12" x 8" BOTTOM MANIFOLD INVERT (12" PIPE):0.40 BOTTOM OF STONE:0.00 PROPOSED LAYOUT 168 STORMTECH SC-160LP CHAMBERS 24 STORMTECH SC-160LP END CAPS STONE ABOVE (in) STONE BELOW (in) 40 STONE VOID 3044 INSTALLED SYSTEM VOLUME (CF) (PERIMETER STONE INCLUDED) (COVER STONE INCLUDED) (BASE STONE INCLUDED) 2942 SYSTEM AREA (SF) 301.7 SYSTEM PERIMETER (ft) MAX FLOWINVERT*DESCRIPTIONITEM ON LAYOUTPART TYPE -1.17" 0.96" 12" x 8" REDUCING CONCENTRIC MOLDED FITTINGS (12" PIPE) 12" x 8" REDUCING CONCENTRIC MOLDED FITTINGS (8" PIPE)AMANIFOLD -1.17" 0.96" 12" x 8" REDUCING CONCENTRIC MOLDED FITTINGS (12" PIPE) 12" x 8" REDUCING CONCENTRIC MOLDED FITTINGS (8" PIPE)BMANIFOLD 3.0 CFS IN(DESIGN BY ENGINEER / PROVIDED BY OTHERS)CCONCRETE STRUCTURE W/WEIR 3.0 CFS IN(DESIGN BY ENGINEER / PROVIDED BY OTHERS)DCONCRETE STRUCTURE W/WEIR ISOLATOR ROW PLUS (SEE DETAIL) PLACE MINIMUM 12.50' OF ADSPLUS625 WOVEN GEOTEXTILE OVER BEDDING STONE AND UNDERNEATH CHAMBER FEET FOR SCOUR PROTECTION AT ALL CHAMBER INLET ROWS BED LIMITS 123.87'27.00'114.33'25.00'NOTES •THE SITE DESIGN ENGINEER MUST REVIEW ELEVATIONS AND IF NECESSARY ADJUST GRADING TO ENSURE THE CHAMBER COVER REQUIREMENTS ARE MET. •NOT FOR CONSTRUCTION: THIS LAYOUT IS FOR DIMENSIONAL PURPOSES ONLY TO PROVE CONCEPT & THE REQUIRED STORAGE VOLUME CAN BE ACHIEVED ON SITE. *INVERT ABOVE BASE OF CHAMBER AB D C STORMTECH SC-160 LP SYSTEM 34SCALE: NTS ISOLATOR ROW PLUS (SEE DETAIL) PLACE MINIMUM 12.50' OF ADSPLUS625 WOVEN GEOTEXTILE OVER BEDDING STONE AND UNDERNEATH CHAMBER FEET FOR SCOUR PROTECTION AT ALL CHAMBER INLET ROWS BED LIMITS NOTES •THE SITE DESIGN ENGINEER MUST REVIEW ELEVATIONS AND IF NECESSARY ADJUST GRADING TO ENSURE THE CHAMBER COVER REQUIREMENTS ARE MET. •NOT FOR CONSTRUCTION: THIS LAYOUT IS FOR DIMENSIONAL PURPOSES ONLY TO PROVE CONCEPT & THE REQUIRED STORAGE VOLUME CAN BE ACHIEVED ON SITE. 70.06'24.92'64.52'22.92'A C B CONCEPTUAL ELEVATIONS MAXIMUM ALLOWABLE GRADE (TOP OF PAVEMENT/UNPAVED):11.50 MINIMUM ALLOWABLE GRADE (UNPAVED WITH TRAFFIC):3.17 MINIMUM ALLOWABLE GRADE (UNPAVED NO TRAFFIC):2.67 MINIMUM ALLOWABLE GRADE (TOP OF RIGID CONCRETE PAVEMENT):2.67 MINIMUM ALLOWABLE GRADE (BASE OF FLEXIBLE PAVEMENT):2.67 TOP OF STONE:2.00 TOP OF SC-160LP CHAMBER:1.50 8" x 8" BOTTOM MANIFOLD INVERT:0.58 8" ISOLATOR ROW PLUS INVERT:0.58 8" ISOLATOR ROW PLUS INVERT:0.58 BOTTOM OF SC-160LP CHAMBER:0.50 BOTTOM OF STONE:0.00 PROPOSED LAYOUT 95 STORMTECH SC-160LP CHAMBERS 26 STORMTECH SC-160LP END CAPS 6 STONE ABOVE (in) 6 STONE BELOW (in) 40 STONE VOID 1761 INSTALLED SYSTEM VOLUME (CF) (PERIMETER STONE INCLUDED) (COVER STONE INCLUDED) (BASE STONE INCLUDED) 1713 SYSTEM AREA (SF) 190.0 SYSTEM PERIMETER (ft) MAX FLOWINVERT*DESCRIPTIONITEM ON LAYOUTPART TYPE 0.96"8" x 8" BOTTOM MANIFOLD, MOLDED FITTINGSAMANIFOLD (DESIGN BY ENGINEER / PROVIDED BY OTHERS)BCONCRETE STRUCTURE W/WEIR 2.2 CFS IN(DESIGN BY ENGINEER / PROVIDED BY OTHERS)CCONCRETE STRUCTURE W/WEIR *INVERT ABOVE BASE OF CHAMBER STORMTECH SC-160 LP SYSTEM 2-11SCALE: NTS 82 14 6 6 40 1544 1508 223.1 CONCEPTUAL ELEVATIONS MAXIMUM ALLOWABLE GRADE (TOP OF PAVEMENT/UNPAVED):11.50 MINIMUM ALLOWABLE GRADE (UNPAVED WITH TRAFFIC):3.17 MINIMUM ALLOWABLE GRADE (UNPAVED NO TRAFFIC):2.67 MINIMUM ALLOWABLE GRADE (TOP OF RIGID CONCRETE PAVEMENT):2.67 MINIMUM ALLOWABLE GRADE (BASE OF FLEXIBLE PAVEMENT):2.67 TOP OF STONE:2.00 TOP OF SC-160LP CHAMBER:1.50 8" ISOLATOR ROW PLUS INVERT:0.58 12" x 8" BOTTOM MANIFOLD INVERT (8" PIPE):0.58 BOTTOM OF SC-160LP CHAMBER:0.50 12" x 8" BOTTOM MANIFOLD INVERT (12" PIPE):0.40 BOTTOM OF STONE:0.00 PROPOSED LAYOUT 28 STORMTECH SC-160LP CHAMBERS 8 STORMTECH SC-160LP END CAPS 6 STONE ABOVE (in) 6 STONE BELOW (in) 40 STONE VOID 579 INSTALLED SYSTEM VOLUME (CF) (PERIMETER STONE INCLUDED) (COVER STONE INCLUDED) (BASE STONE INCLUDED) 579 SYSTEM AREA (SF) 132.8 SYSTEM PERIMETER (ft) MAX FLOWINVERT*DESCRIPTIONITEM ON LAYOUTPART TYPE -1.17" 0.96" 12" x 8" REDUCING CONCENTRIC MOLDED FITTINGS (12" PIPE) 12" x 8" REDUCING CONCENTRIC MOLDED FITTINGS (8" PIPE)AMANIFOLD 1.5 CFS IN(DESIGN BY ENGINEER / PROVIDED BY OTHERS)BCONCRETE STRUCTURE W/WEIR ISOLATOR ROW PLUS (SEE DETAIL) PLACE MINIMUM 12.50' OF ADSPLUS625 WOVEN GEOTEXTILE OVER BEDDING STONE AND UNDERNEATH CHAMBER FEET FOR SCOUR PROTECTION AT ALL CHAMBER INLET ROWS BED LIMITS 56.05'10.33'50.28'8.33'NOTES •THE SITE DESIGN ENGINEER MUST REVIEW ELEVATIONS AND IF NECESSARY ADJUST GRADING TO ENSURE THE CHAMBER COVER REQUIREMENTS ARE MET. •NOT FOR CONSTRUCTION: THIS LAYOUT IS FOR DIMENSIONAL PURPOSES ONLY TO PROVE CONCEPT & THE REQUIRED STORAGE VOLUME CAN BE ACHIEVED ON SITE. *INVERT ABOVE BASE OF CHAMBER B A STORMTECH SC-160 LP SYSTEM 2-33SCALE: NTS CONCEPTUAL ELEVATIONS MAXIMUM ALLOWABLE GRADE (TOP OF PAVEMENT/UNPAVED):11.50 MINIMUM ALLOWABLE GRADE (UNPAVED WITH TRAFFIC):3.17 MINIMUM ALLOWABLE GRADE (UNPAVED NO TRAFFIC):2.67 MINIMUM ALLOWABLE GRADE (TOP OF RIGID CONCRETE PAVEMENT):2.67 MINIMUM ALLOWABLE GRADE (BASE OF FLEXIBLE PAVEMENT):2.67 TOP OF STONE:2.00 TOP OF SC-160LP CHAMBER:1.50 8" ISOLATOR ROW PLUS INVERT:0.58 12" x 8" BOTTOM MANIFOLD INVERT (8" PIPE):0.58 BOTTOM OF SC-160LP CHAMBER:0.50 12" x 8" BOTTOM MANIFOLD INVERT (12" PIPE):0.40 BOTTOM OF STONE:0.00 PROPOSED LAYOUT 88 STORMTECH SC-160LP CHAMBERS 20 STORMTECH SC-160LP END CAPS 6 STONE ABOVE (in) 6 STONE BELOW (in) 40 STONE VOID 1612 INSTALLED SYSTEM VOLUME (CF) (PERIMETER STONE INCLUDED) (COVER STONE INCLUDED) (BASE STONE INCLUDED) 1562 SYSTEM AREA (SF) 200.5 SYSTEM PERIMETER (ft) MAX FLOWINVERT*DESCRIPTIONITEM ON LAYOUTPART TYPE -1.17" 0.96" 12" x 8" REDUCING CONCENTRIC MOLDED FITTINGS (12" PIPE) 12" x 8" REDUCING CONCENTRIC MOLDED FITTINGS (8" PIPE)AMANIFOLD 2.2 CFS IN(DESIGN BY ENGINEER / PROVIDED BY OTHERS)BCONCRETE STRUCTURE W/WEIR 77.40'22.83'71.63'20.83'NOTES•THE SITE DESIGN ENGINEER MUST REVIEW ELEVATIONS AND IF NECESSARY ADJUST GRADING TO ENSURE THE CHAMBER COVER REQUIREMENTS ARE MET.•NOT FOR CONSTRUCTION: THIS LAYOUT IS FOR DIMENSIONAL PURPOSES ONLY TO PROVE CONCEPT & THE REQUIRED STORAGE VOLUME CAN BE ACHIEVED ON SITE. ISOLATOR ROW PLUS (SEE DETAIL) PLACE MINIMUM 12.50' OF ADSPLUS625 WOVEN GEOTEXTILE OVER BEDDING STONE AND UNDERNEATH CHAMBER FEET FOR SCOUR PROTECTION AT ALL CHAMBER INLET ROWS BED LIMITS A B STORMTECH SC-160 LP SYSTEM 55SCALE: NTS CONCEPTUAL ELEVATIONS MAXIMUM ALLOWABLE GRADE (TOP OF PAVEMENT/UNPAVED):11.50 MINIMUM ALLOWABLE GRADE (UNPAVED WITH TRAFFIC):3.17 MINIMUM ALLOWABLE GRADE (UNPAVED NO TRAFFIC):2.67 MINIMUM ALLOWABLE GRADE (TOP OF RIGID CONCRETE PAVEMENT):2.67 MINIMUM ALLOWABLE GRADE (BASE OF FLEXIBLE PAVEMENT):2.67 TOP OF STONE:2.00 TOP OF SC-160LP CHAMBER:1.50 8" ISOLATOR ROW PLUS INVERT:0.58 8" ISOLATOR ROW PLUS INVERT:0.58 12" x 8" BOTTOM MANIFOLD INVERT (8" PIPE):0.58 BOTTOM OF SC-160LP CHAMBER:0.50 12" x 8" BOTTOM MANIFOLD INVERT (12" PIPE):0.40 BOTTOM OF STONE:0.00 PROPOSED LAYOUT 80 STORMTECH SC-160LP CHAMBERS 20 STORMTECH SC-160LP END CAPS 6 STONE ABOVE (in) 6 STONE BELOW (in) 40 STONE VOID 1474 INSTALLED SYSTEM VOLUME (CF) (PERIMETER STONE INCLUDED) (COVER STONE INCLUDED) (BASE STONE INCLUDED) 1431 SYSTEM AREA (SF) 172.0 SYSTEM PERIMETER (ft) MAX FLOWINVERT*DESCRIPTIONITEM ON LAYOUTPART TYPE -1.17" 0.96" 12" x 8" REDUCING CONCENTRIC MOLDED FITTINGS (12" PIPE) 12" x 8" REDUCING CONCENTRIC MOLDED FITTINGS (8" PIPE)AMANIFOLD (DESIGN BY ENGINEER / PROVIDED BY OTHERS)BCONCRETE STRUCTURE W/WEIR 3.0 CFS IN(DESIGN BY ENGINEER / PROVIDED BY OTHERS)CCONCRETE STRUCTURE W/WEIR ISOLATOR ROW PLUS (SEE DETAIL) PLACE MINIMUM 12.50' OF ADSPLUS625 WOVEN GEOTEXTILE OVER BEDDING STONE AND UNDERNEATH CHAMBER FEET FOR SCOUR PROTECTION AT ALL CHAMBER INLET ROWS BED LIMITS 63.17'22.83'57.40'20.83'NOTES •THE SITE DESIGN ENGINEER MUST REVIEW ELEVATIONS AND IF NECESSARY ADJUST GRADING TO ENSURE THE CHAMBER COVER REQUIREMENTS ARE MET. •NOT FOR CONSTRUCTION: THIS LAYOUT IS FOR DIMENSIONAL PURPOSES ONLY TO PROVE CONCEPT & THE REQUIRED STORAGE VOLUME CAN BE ACHIEVED ON SITE. *INVERT ABOVE BASE OF CHAMBER A C B STORMTECH SC-160 LP SYSTEM 76SCALE: NTS 749-01Alpine Job #: THIS SHEET IS INTENDED TO BE PRINTED IN COLOR TO FULLY UNDERSTAND THE INFORMATION BEING PRESENTED. 2025 ENCOMPASS DESIGN INC.C AN AFFORDABLE HOUSING DEVELOPMENT:ROCKY MOUNTAIN FLATSBOZEMAN, MONTANA1535 liberty lane suite 110b missoula, montana 59808 phone: 406.540.4437 24.115edinc Job #: SITE PLAN REVIEW: 05/29/2025 REV. 02: SP RESUBMITTAL #2 F6 DETAILS STORMTECH SC-160 LP SYSTEM 81SCALE: NTS CONCEPTUAL ELEVATIONS MAXIMUM ALLOWABLE GRADE (TOP OF PAVEMENT/UNPAVED):11.50 MINIMUM ALLOWABLE GRADE (UNPAVED WITH TRAFFIC):3.17 MINIMUM ALLOWABLE GRADE (UNPAVED NO TRAFFIC):2.67 MINIMUM ALLOWABLE GRADE (TOP OF RIGID CONCRETE PAVEMENT):2.67 MINIMUM ALLOWABLE GRADE (BASE OF FLEXIBLE PAVEMENT):2.67 TOP OF STONE:2.00 TOP OF SC-160LP CHAMBER:1.50 8" ISOLATOR ROW PLUS INVERT:0.58 8" ISOLATOR ROW PLUS INVERT:0.58 12" x 8" BOTTOM MANIFOLD INVERT (8" PIPE):0.58 BOTTOM OF SC-160LP CHAMBER:0.50 12" x 8" BOTTOM MANIFOLD INVERT (12" PIPE):0.40 BOTTOM OF STONE:0.00 PROPOSED LAYOUT 36 STORMTECH SC-160LP CHAMBERS 12 STORMTECH SC-160LP END CAPS 6 STONE ABOVE (in) 6 STONE BELOW (in) 40 STONE VOID 706 INSTALLED SYSTEM VOLUME (CF) (PERIMETER STONE INCLUDED) (COVER STONE INCLUDED) (BASE STONE INCLUDED) 698 SYSTEM AREA (SF) 126.9 SYSTEM PERIMETER (ft) MAX FLOWINVERT*DESCRIPTIONITEM ON LAYOUTPART TYPE -1.17" 0.96" 12" x 8" REDUCING CONCENTRIC MOLDED FITTINGS (12" PIPE) 12" x 8" REDUCING CONCENTRIC MOLDED FITTINGS (8" PIPE)AMANIFOLD 1.5 CFS IN(DESIGN BY ENGINEER / PROVIDED BY OTHERS)BCONCRETE STRUCTURE W/WEIR (DESIGN BY ENGINEER / PROVIDED BY OTHERS)CCONCRETE STRUCTURE W/WEIR ISOLATOR ROW PLUS (SEE DETAIL) PLACE MINIMUM 12.50' OF ADSPLUS625 WOVEN GEOTEXTILE OVER BEDDING STONE AND UNDERNEATH CHAMBER FEET FOR SCOUR PROTECTION AT ALL CHAMBER INLET ROWS BED LIMITS 48.94'14.50'43.17'12.50'NOTES •THE SITE DESIGN ENGINEER MUST REVIEW ELEVATIONS AND IF NECESSARY ADJUST GRADING TO ENSURE THE CHAMBER COVER REQUIREMENTS ARE MET. •NOT FOR CONSTRUCTION: THIS LAYOUT IS FOR DIMENSIONAL PURPOSES ONLY TO PROVE CONCEPT & THE REQUIRED STORAGE VOLUME CAN BE ACHIEVED ON SITE. *INVERT ABOVE BASE OF CHAMBER A BC COMBO MANHOLE & CURB INLET DETAIL5SCALE: NTS NYLOPLAST DRAIN BASIN DETAIL2SCALE: NTS NOTES 1.8-30" (200-750 mm) GRATES/SOLID COVERS SHALL BE DUCTILE IRON PER ASTM A536 GRADE 70-50-05 2.12-30" (300-750 mm) FRAMES SHALL BE DUCTILE IRON PER ASTM A536 GRADE 70-50-05 3.DRAIN BASIN TO BE CUSTOM MANUFACTURED ACCORDING TO PLAN DETAILS 4.DRAINAGE CONNECTION STUB JOINT TIGHTNESS SHALL CONFORM TO ASTM D3212 FOR CORRUGATED HDPE (ADS & HANCOR DUAL WALL) & SDR 35 PVC 5.FOR COMPLETE DESIGN AND PRODUCT INFORMATION: WWW.NYLOPLAST-US.COM 6.TO ORDER CALL: 800-821-6710 A PART #GRATE/SOLID COVER OPTIONS 8" (200 mm)2808AG PEDESTRIAN LIGHT DUTY STANDARD LIGHT DUTY SOLID LIGHT DUTY 10" (250 mm)2810AG PEDESTRIAN LIGHT DUTY STANDARD LIGHT DUTY SOLID LIGHT DUTY 12" (300 mm)2812AG PEDESTRIAN AASHTO H-10 STANDARD AASHTO H-20 SOLID AASHTO H-20 15" (375 mm)2815AG PEDESTRIAN AASHTO H-10 STANDARD AASHTO H-20 SOLID AASHTO H-20 18" (450 mm)2818AG PEDESTRIAN AASHTO H-10 STANDARD AASHTO H-20 SOLID AASHTO H-20 24" (600 mm)2824AG PEDESTRIAN AASHTO H-10 STANDARD AASHTO H-20 SOLID AASHTO H-20 30" (750 mm)2830AG PEDESTRIAN AASHTO H-20 STANDARD AASHTO H-20 SOLID AASHTO H-20 INTEGRATED DUCTILE IRON FRAME & GRATE/SOLID TO MATCH BASIN O.D. GRATE / COVER TYPE VARIES PER BASIN. REFER TO PLAN SHEETS. VARIOUS TYPES OF INLET AND OUTLET ADAPTERS AVAILABLE: 4-30" (100-750 mm) FOR CORRUGATED HDPE WATERTIGHT JOINT (CORRUGATED HDPE SHOWN) BACKFILL MATERIAL BELOW AND TO SIDES OF STRUCTURE SHALL BE ASTM D2321 CLASS I OR II CRUSHED STONE OR GRAVEL AND BE PLACED UNIFORMLY IN 12" (305 mm) LIFTS AND COMPACTED TO MIN OF 90% TRAFFIC LOADS: CONCRETE DIMENSIONS ARE FOR GUIDELINE PUPOSES ONLY. ACTUAL CONCRETE SLAB MUST BE DESIGNED GIVING CONSIDERATION FOR LOCAL SOIL CONDITIONS, TRAFFIC LOADING & OTHER APPLICABLE DESIGN FACTORS ADAPTER ANGLES VARIABLE 0°- 360° ACCORDING TO PLANS 18" (457 mm) MIN WIDTH A AASHTO H-20 CONCRETE SLAB 8" (203 mm) MIN THICKNESS SUMP DEPTH PER PLAN (18" TYPICAL) 4" (102 mm) MIN ON 8-24" (200-600 mm) 6" (152 mm) MIN ON 30" (750 mm) 12" (610 mm) MIN (FOR AASHTO H-20) INVERT ACCORDING TO PLANS MINIMUM PIPE BURIAL DEPTH PER PIPE MANUFACTURER RECOMMENDATION INVERT ACCORDING TO PLANS 15" 1 - 8" - 30" DOME GRATES SHALL BE DUCTILE IRON PER ASTM A536 GRADE 70-50-05. 2 - DRAINAGE CONNECTION STUB JOINT TIGHTNESS SHALL CONFORM TO ASTM D3212 FOR CORRUGATED HDPE (ADS N-12/HANCOR DUAL WALL), N-12 HP, & PVC SEWER (4" - 24"). 3 - 8" - 30" DOME GRATES HAVE NO LOAD RATING (3) VARIOUS TYPES OF INLET & OUTLET ADAPTERS AVAILABLE: 4" - 30" FOR CORRUGATED HDPE (ADS N-12/HANCOR DUAL WALL, ADS/HANCOR SINGLE WALL), N-12 HP, PVC SEWER (EX: SDR 35), PVC DWV (EX: SCH 40), PVC C900/C905, CORRUGATED & RIBBED PVC WATERTIGHT JOINT (CORRUGATED HDPE SHOWN) THE BACKFILL MATERIAL SHALL BE CRUSHED STONE OR OTHER GRANULAR MATERIAL MEETING THE REQUIREMENTS OF CLASS I, CLASS II, OR CLASS III MATERIAL AS DEFINED IN ASTM D2321. BEDDING & BACKFILL FOR SURFACE DRAINAGE INLETS SHALL BE PLACED & COMPACTED UNIFORMLY IN ACCORDANCE WITH ASTM D2321. NYLOPLAST INLINE DRAIN WITH FLAT GRATE DETAIL3SCALE: NTS REFERENCE: ADS NYLOPLAST DWG. NO. 7003-110-057 (1,2) INTERGRATED DUCITLE IRON FRAME & GRATE TO MATCH BASIN O.D. 6" DIA. PIPE STORM DRAIN MANHOLE DETAIL6SCALE: NTS SQUARE STORM DRAIN INLET DETAIL7SCALE: NTS CONCRETE STORM CHASE DETAIL8SCALE: NTS STORM POND SECTION DETAIL4 SCALE: NTS4:1 MAX SIDE SLOPEDEPTH VARIES POND DIMENSIONS PER PLAN FINISH GRADE POND WITH 6" TOPSOIL AND SEED STORM SEWER LINE STORM DRAIN SERVICE LINE9SCALE: NTS SOURCE: COB. STD. DWG. NO: 02720-10 90° ELBOW ALIGN WITH DOWNSPOUT FROM ARCH PLANS 18" MIN. DOWNSPOUT LOCATION PER ARCH PLANS FINISH GRADE SURFACE COMPACTED BACKFILL (SEE SPECS.) BUILDING FOUNDATION 45° ELBOW 6" SERVICE LINE 2% MIN. SERVICE LINE SLOPE IN LINE TEE FITTING FOR NEW INSTALLATIONS. INSERT-A-TEE, OR AS APPROVED BY ENGINEER Rocky Mountain Flats – Stormwater Facilities Operation & Maintenance Plan Page 5 May 26, 2025 ATTACHMENT C ADS Stormtech Isolator Row O&M Manual Isolator® Row O&M Manual 2 Looking down the Isolator Row from the manhole opening, woven geotextile Fabric is shown between the chamber and stone base. StormTech Isolator Row with Overflow Spillway (not to scale) The Isolator® Row Introduction An important component of any Stormwater Pollution Prevention Plan is inspection and maintenance. The StormTech Isolator Row is a technique to inexpensively enhance Total Suspended Solids (TSS) and Total Phosphorus (TP) removal with easy access for inspection and maintenance. The Isolator RowThe Isolator Row is a row of StormTech chambers, either SC-160, SC-310, SC-310-3, SC-740, DC-780, MC-3500 or MC-7200 models, that is surrounded with filter fabric and connected to a closely located manhole for easy access. The fabric-wrapped chambers provide for sediment settling and filtration as stormwater rises in the Isolator Row and passes through the filter fabric. The open bottom chambers and perforated sidewalls (SC-310, SC- 310-3 and SC-740 models) allow stormwater to flow both vertically and horizontally out of the chambers. Sediments are captured in the Isolator Row protecting the adjacent stone and chambers storage areas from sediment accumulation. ADS geotextile fabric is placed between the stone and the Isolator Row chambers. The woven geotextile provides a media for stormwater filtration, a durable surface for maintenance, prevents scour of the underlying stone and remains intact during high pressure jetting. A non-woven fabric is placed over the chambers to provide a filter media for flows passing through the chamber’s sidewall. The non-woven fabric is not required over the SC-160, DC-780, MC-3500 or MC-7200 models as these chambers do not have perforated side walls. The Isolator Row is designed to capture the “first flush” runoff and offers the versatility to be sized on a volume basis or a flow-rate basis. An upstream manhole provides access to the Isolator Row and includes a high/low concept such that stormwater flow rates or volumes that exceed the capacity of the Isolator Row bypass through a manifold to the other chambers. This is achieved with an elevated bypass manifold or a high-flow weir. This creates a differential between the Isolator Row row of chambers and the manifold to the rest of the system, thus allowing for settlement time in the Isolator Row. After Stormwater flows through the Isolator Row and into the rest of the chamber system it is either exfiltrated into the soils below or passed at a controlled rate through an outlet manifold and outlet control structure. The Isolator Row may be part of a treatment train system. The treatment train design and pretreatment device selection by the design engineer is often driven by regulatory requirements. Whether pretreatment is used or not, StormTech recommend using the Isolator Row to minimize maintenance requirements and maintenance costs. Note: See the StormTech Design Manual for detailed information on designing inlets for a StormTech system, including the Isolator Row. ECCENTRICHEADER MANHOLEWITHOVERFLOWWEIR STORMTECHISOLATOR ROW OPTIONAL PRE-TREATMENT OPTIONAL ACCESS STORMTECH CHAMBERS 3 Inspection The frequency of inspection and maintenance varies by location. A routine inspection schedule needs to be established for each individual location based upon site specific variables. The type of land use (i.e. industrial, commercial, residential), anticipated pollutant load, percent imperviousness, climate, etc. all play a critical role in determining the actual frequency of inspection and maintenance practices. At a minimum, StormTech recommends annual inspections. Initially, the Isolator Row should be inspected every 6 months for the first year of operation. For subsequent years, the inspection should be adjusted based upon previous observation of sediment deposition. The Isolator Row incorporates a combination of standard manhole(s) and strategically located inspection ports (as needed). The inspection ports allow for easy access to the system from the surface, eliminating the need to perform a confined space entry for inspection purposes. If upon visual inspection it is found that sediment has accumulated, a stadia rod should be inserted to determine the depth of sediment. When the average depth of sediment exceeds 3 inches throughout the length of the Isolator Row, clean-out should be performed. Maintenance The Isolator Row was designed to reduce the cost of periodic maintenance. By “isolating” sediments to just one row, costs are dramatically reduced by eliminating the need to clean out each row of the entire storage bed. If inspection indicates the potential need for maintenance, access is provided via a manhole(s) located on the end(s) of the row for cleanout. If entry into the manhole is required, please follow local and OSHA rules for a confined space entries. Maintenance is accomplished with the JetVac process. The JetVac process utilizes a high pressure water nozzle to propel itself down the Isolator Row while scouring and suspending sediments. As the nozzle is retrieved, the captured pollutants are flushed back into the manhole for vacuuming. Most sewer and pipe maintenance companies have vacuum/JetVac combination vehicles. Selection of an appropriate JetVac nozzle will improve maintenance efficiency. Fixed nozzles designed for culverts or large diameter pipe cleaning are preferable. Rear facing jets with an effective spread of at least 45” are best. JetVac reels can vary in length. For ease of maintenance, ADS recommends Isolator Row lengths up to 200" (61 m). The JetVac process shall only be performed on StormTech Isolator Rows that have AASHTO class 1 woven geotextile (as specified by StormTech) over their angular base stone. Isolator Row Inspection/Maintenance StormTech Isolator Row (not to scale) Note: Non-woven fabric is only required over the inlet pipe connection into the end cap for SC-160LP, DC-780, MC-3500 and MC-7200 chamber models and is not required over the entire Isolator Row. Isolator Row Step By Step Maintenance Procedures Step 1 Inspect Isolator Row for sediment. A) Inspection ports (if present) i. Remove lid from floor box frame ii. Remove cap from inspection riser iii. Using a flashlight and stadia rod,measure depth of sediment and record results on maintenance log. iv. If sediment is at or above 3 inch depth, proceed to Step 2. If not, proceed to Step 3. B) All Isolator Row i. Remove cover from manhole at upstream end of Isolator Row ii. Using a flashlight, inspect down Isolator Row through outlet pipe 1. Mirrors on poles or cameras may be used to avoid a confined space entry 2. Follow OSHA regulations for confined space entry if entering manhole iii. If sediment is at or above the lower row of sidewall holes (approximately 3 inches), proceed to Step 2. If not, proceed to Step 3. Step 2 Clean out Isolator Row using the JetVac process. A) A fixed floor cleaning nozzle with rear facing nozzle spread of 45 inches or more is preferable B) Apply multiple passes of JetVac until backflush water is clean C) Vacuum manhole sump as required Step 3 Replace all caps, lids and covers, record observations and actions. Step 4 Inspect & clean catch basins and manholes upstream of the StormTech system. ADS “Terms and Conditions of Sale” are available on the ADS website, www.ads-pipe.com The ADS logo and the Green Stripe are registered trademarks of Advanced Drainage Systems, Inc. Stormtech® and the Isolator® Row are registered trademarks of StormTech, Inc. © 2022 Advanced Drainage Systems, Inc. #11011 2/22 CS )( Sample Maintenance Log Date Stadia Rod Readings Sedi- ment Depth (1)–(2) Observations/Actions InspectorFixed point to chamber bottom (1) Fixed point to top of sediment (2) 3/15/11 6.3 ft none New installation. Fixed point is CI frame at grade DJM 9/24/11 6.2 0.1 ft Some grit felt SM 6/20/13 5.8 0.5 ft Mucky feel, debris visible in manhole and in Isolator Row, maintenance due NV 7/7/13 6.3 ft 0 System jetted and vacuumed DJM adspipe.com 800-821-6710 Rocky Mountain Flats – Stormwater Facilities Operation & Maintenance Plan Page 6 May 26, 2025 ATTACHMENT D Sample Inspection Form Chapter 6 - Storm Drainage Design 6-44 City of Bozeman Design and Construction Standards Stormwater Facility Inspection Form Section 1: General Information Facility ID: Facility Type: Choose an item. Date/Time: Click or tap to enter a date. Owner: Contact: Inspector’s Name, contact info: Choose an item. Location/Access info: Type of Inspection: ☐ Routine, Dry Weather ☐ Routine, Wet Weather ☐ Complaint Driven ☐ Other: __________________ Section 2: Weather and Discharge Information Most recent precipitation or melt: Temperature: Is a stormwater discharge occurring? ☐ Yes ☐ No If yes, what is the source and quality of discharge? Is an illegal discharge occurring? ☐ Yes ☐ No If yes, what is the source and quality of discharge? Section 3: Facility Maintenance Priority ☐ Low: Stormwater facility appears to be functioning as designed. Continue scheduled maintenance. ☐ Medium: Stormwater facility requires minor to moderate sediment and vegetation maintenance to mitigate the risk of flooding, waterway pollution, and infrastructure failure. ☐ High: Stormwater facility requires significant sediment dredging, vegetation removal, and/or infrastructure repairs to restore function. Notes, Findings & Recommendations: Inspector’s Signature: ________________________________ Date: ___________________ Chapter 6 - Storm Drainage Design 6-45 City of Bozeman Design and Construction Standards Section 4: Qualitative Analysis Components # Items Conditions Results Notes and Required Actions General Degraded, missing, or inadequate Yes 1.1 Accessibility maintenance access? No ☐☐ Trash, sediment, and waste within 1.2 Debris ☐Yes and around the facility? ☐ No Overgrown or dead cattails, Yes 1.3 Vegetation woody shrubs, weeds, grass, and ☐ trees? ☐ No Infrastructure Damaged inlet pipe, outlet pipe, Yes1.4 ☐ Condition outfall structure, or fencing? ☐ No Facility Condition Pretreatment Bay Clogged, obstructed, or filled 2.1 ☐ Yes or Facility pretreatment forebay or facility? ☐ No 2.2 Storage Bay Clogged or filled storage bay? ☐ Yes ☐ No Stagnant water with infiltration Groundwater or Yes 2.3 greater than 48 hours post-rain ☐ Standing Water event? ☐ No 2.4 Flow Path Clogged or obstructed flow path? ☐ Yes ☐ No Barren or exposed surfaces on Yes 2.5 Side Slopes ☐ Facility’s side slopes and bottom? ☐ No Maintenance Maintenance Plan Is there a written plan specific to ☐ Yes 3.1 or Agreement this facility? ☐ No Yes 3.2 Implementation Is there evidence of maintenance? ☐ ☐ No Chapter 6 - Storm Drainage Design 6-46 City of Bozeman Design and Construction Standards Section 5: Quantitative Analysis Vegetation Cover type % Within facility Notes Bare ground Aquatics Grasses/Herbaceou Trees >3” DBH Shrubs Total 100 Elevation Analysis Location Reading (ft) Elevation (ft) Notes SRV#CP Control Point SRV#1 Inlet SRV#2 Outlet SRV#3 Center SRV#4 North of Center SRV#5 East of Center SRV#6 South of Center SRV#7 West of center SRV#8 Berm or overflow SRV#9 Summary Chapter 6 - Storm Drainage Design 6-47 City of Bozeman Design and Construction Standards Section 6: Facility Maintenance Inspection Exhibit Chapter 6 - Storm Drainage Design 6-48 City of Bozeman Design and Construction Standards Photo 1 description Photo 2 description Section 7: Photo Log Appendix F Stormwater Design Report for The Homestead at Buffalo Run STORM WATER DESIGN REPORT FOR THE HOMESTEAD AT BUFFALO RUN BOZEMAN GALLATIN COUNTY MONTANA Prepared By: Morrison-Maierle, Inc. 2880 Technology Blvd. West P.O. Box 1113 Bozeman, Montana 59771-1113 Engineer: Lee Hageman, P.E. Date: July 26, 2022 (Revision 3) May 24, 2022 (Revision 2) October 15, 2021 (Original) File:6475.005 7/26/2022 THE HOMESTEAD AT BUFFALO RUN STORM WATER DESIGN REPORT _________________________________________________________________________ Page 2 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Table of Contents 1 Introduction ............................................................................................................................ 3 2 Proposed Development ......................................................................................................... 3 2.1 Project Location and Description .................................................................................... 3 2.2 Development Horizon ..................................................................................................... 3 3 Existing Area Conditions ........................................................................................................ 3 3.1 Existing Land Cover and Slopes .................................................................................... 3 3.2 NRCS Soils ..................................................................................................................... 4 3.3 Site Groundwater Levels ................................................................................................ 4 3.4 Existing Drainage Features ............................................................................................ 4 4 Major Drainage Basins .......................................................................................................... 4 5 Methodologies ....................................................................................................................... 5 5.1 Design Methodology ....................................................................................................... 5 5.2 Design Storm Analyses .................................................................................................. 7 5.3 Storm Drain Capture and Conveyance ........................................................................... 7 5.4 Storm Water Treatment Facilities ................................................................................. 11 5.5 Overflow ....................................................................................................................... 17 5.6 Irrigation Ditches ........................................................................................................... 18 6 Maintenance ........................................................................................................................ 19 7 Conclusions ......................................................................................................................... 19 List of Exhibits Exhibit A Vicinity Map Exhibit B Post-Development Drainage Basins List of Appendices Appendix A NRCS Soil Report Appendix B Groundwater Data Appendix C Storm Water Calculations Appendix D Operation and Maintenance Manual Appendix E Irrigation Ditch Information _________________________________________________________________________ Page 3 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT 1 INTRODUCTION This report provides a basis of storm drain design for the Homestead at Buffalo Run Site Plan (Buffalo Run) project and is submitted in conjunction with the site plan. The storm drain system serving Buffalo Run was designed and shall be installed in accordance with the following:  The City of Bozeman Design Standards and Specifications Policy (dated May 1, 2017) o Including Addendum Numbers 1 thru 6  Montana Public Works Standard Specifications (MPWSS) – Current Edition  The City of Bozeman Modifications to MPWSS 2 PROPOSED DEVELOPMENT 2.1 Project Location and Description The Buffalo Run Site Plan is located off of Kurk Drive between S 31st Ave and Fowler Lane. The property is a 20.33-acre tract of land situated in the N ½ SW ¼ SW ¼ of Section 23, located in Township 2 South, Range 5 East in Gallatin County, Montana. This project has been annexed and zoned into the City of Bozeman, Montana. The property is currently zoned R-4. See Exhibit A for location details. Buffalo Run Bozeman, LLC (BRB) plans to construct a 237-unit multi-family apartment community and a clubhouse as part of this development. The project is intended to be developed, owned, and operated by a single ownership group. 2.2 Development Horizon The project will begin development a soon as the required approvals are in place, tentatively scheduled for 2022. 3 EXISTING AREA CONDITIONS 3.1 Existing Land Cover and Slopes The existing property is primarily vacant, agricultural land but also includes a house, lawn, shop facility, and driveway surfacing. Additionally, the current site includes an existing pond. The existing slopes range from 0% to 4% and generally drain from south to north. An irrigation ditch exists on both sides of Fowler lane on the west side of the property. Additionally, an upstream seepage ditch feeds the existing pond and discharges into an irrigation ditch that bisects the property. These existing facilities are described further in the sections below, along with how they are planning to be addressed for this development. _________________________________________________________________________ Page 4 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT 3.2 NRCS Soils Data on existing site soils is provided in the Gallatin County Area, Montana Soil Survey dated July 20, 2019 through Web Soil Survey (WSS) operated by the United States Department of Agriculture (USDA) Natural Resources Conservation Service (NRCS). According to information obtained from WSS, the Phase 1 contains three basic soil types – Hyalite- Beaverton Complex, Turner Loam, and Meadowcreek Loam. See Appendix A for the complete Soil Resource Report. 3.3 Site Groundwater Levels Groundwater levels beneath the proposed subdivision experience seasonal variations but are generally quite high. The groundwater levels onsite range between approximately 1 and 5 feet below existing grade based on well monitoring performed from March 2020 to September of 2021. See complete groundwater data in Appendix B, including a map showing the locations of each well. High groundwater was a major design factor in the design of the infrastructure and required a substantial amount of fill be placed within the site. The site fill permitted the proposed drainage pipe to be designed to include sufficient cover and slope to convey the required design storm to the proposed subsurface storm treatment structures. Subsurface storm treatment structures were designed with bottom elevations above the seasonal high ground water level to ensure they will drain as required. Stormwater treatment structures designated onsite were designed with sufficient storage to retain the entire stormwater volume from contributing stormwater basins during the design storm. The contributing stormwater basin to the existing pond onsite was minimized as possible, with sufficient storage above the seasonally high groundwater elevation. 3.4 Existing Drainage Features As previously noted, two irrigation ditches exist within the property. One ditch lies within east side of the existing Fowler Lane easement and functions as a barrow/drainage ditch as well as conveyance facility for some irrigation water. An additional ditch bisects the property and is a lateral from the east Fowler Lane borrow ditch. This ditch conveys irrigation water for “waste and seepage” water rights holders. 4 MAJOR DRAINAGE BASINS Post-development runoff from the public rights-of-way (ROWs) and interior lots were used to size the proposed storm water treatment facilities. The site is split into twenty-three (23) major post-development drainage basins based on the receiving treatment facility. These major basins are further subdivided into a total of 41 subbasins to evaluate gutter spread and inlet capture for each sub-basin. Basin X-1 drains offsite due to site constraints with grading tie-ins and limitations from groundwater elevations, but the area was minimized to the extent feasible feasible. Basins were delineated based on proposed contours of the site. Please refer to Exhibit B for a visual representation of the major drainage basins and sub-basins used for the analysis. The pre-development drainage basin considered the longest time of concentration and conservatively estimated the runoff coefficient to be 0.2. _________________________________________________________________________ Page 5 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT 5 METHODOLOGIES This section documents the methodologies and assumptions used to conduct the storm water runoff analyses for the project. Drainage plan methodologies and analyses are based on the City of Bozeman’s Design Standards and Specifications Policy. 5.1 Design Methodology The storm water management system for the proposed development utilizes a system of curb, gutter, inlets, piping, and curb cut and surface drainage features to capture and convey stormwater. Subsurface retention structures (i.e., Stormtech®), Low-Impact-Design (LID) Stormwater Basins, and a Hydrodynamic Separator are proposed to treat storm water runoff. Summaries of runoff estimates, inlet and piping capacities, and treatment volumes are provided in the sections that follow. The stormwater design utilizes retention storage for the post- development condition, and the volume of stormwater created during the 10-year design storm is less than the pre-development condition. The pre-development condition assumed a runoff coefficient of 0.2 based on undeveloped pastureland to be conservative. A summary of the pre- and post-development runoff volume calculations is proved in the table below. Table 1: Pre- versus Pos-Development Conditions ENTIRE SITE Sub-basin Area (acres) Runoff Coefficient Tc (min) Stormwater Discharge Volume during 10-yr Storm (ft3) Treatment Facility Treatment Facility Type Pre-Development Buffalo Run - Pre 20.33 0.20 48.80 12,103 NONE NONE Post-Development Buffalo Run - Post (Combined) 20.33 0.73 Varies 4,135 VARIOUS VARIOUS NOTE: There is a net decrease in stormwater discharge during the 10-yr, 2-hr design storm due to use of retention facilities throughout the site that capture the entire 10-yr storm volume Post-Development – Site and Roads Onsite basins (interior parking and buildings) were designed to capture and retain the design storm to the extent feasible. Public road corridors were designed to capture and convey stormwater runoff separately from onsite areas using underground storage units to the extent practicable. Post-Development - Fowler Stormwater design along Fowler was performed in coordination with the City of to provide an immediate solution for the current development while also considering the future buildout of the Fowler Lane corridor. The current interim solution includes a mix of surface capture and _________________________________________________________________________ Page 6 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT treatment for the eastern side of the ROW and inlet capture, hydrodynamic separation treatment, and discharge to the existing eastern barrow ditch along Fowler. The trunk main is proposed to convey any captured stormwater from the east side of fowler and convey it to a hydrodynamic separation treatment unit prior to discharging back to the barrow ditch. Future Buildout Considerations – Fowler Lane Future buildout of Fowler Lane was considered by proposing a larger stormwater trunk main with sufficient capacity to convey future flows within the Fowler Lane corridor. The capacity analysis for this main considered the City of Bozeman’s 25-yr/2-hr design storm at the ultimate buildout of the Fowler ROW (62’ TBC-TBC) from Blackwood Road to the north end of the project site. An 18” PVC storm main is proposed to be installed along the entire property frontage to provide extension capabilities along the Fowler corridor. This trunk main is intended to convey treated stormwater to a future regional stormwater treatment facility, as indicated by the City of Bozeman. Based on the planned corridor dimensions above, a future runoff coefficient was estimated to be 0.77, which was adjusted to 0.85 by multiplying by the frequency factor. The time of concentration was conservatively assumed to be 9 minutes for a total area of approximately 3 acres. Based on these assumptions, the expected peak flow 6.64 cfs. An 18” A-2000 PVC storm main installed at 1.5% has a capacity of 15.3 cfs at a design depth of 75% (d/D). Calculations for the future trunk main have been provided in Appendix C. The hydrodynamic separation treatment unit that is proposed to be installed immediately upstream of the outfall of the trunk main into the existing east Fowler Lane barrow ditch. The hydrodynamic separator was designed in coordination with Contech Engineered Solutions LLC and was sized with sufficient capacity to treat the stormwater quality (SWQ) volume (first 0.5 inches) for the full buildout condition for the Fowler Corridor with the 62’ road section and 100’ ROW. The CDS 2020-5 unit specified treats the SWQ volume and was designed by the manufacturer to meet the State of Montana’s requirements to remove trash, oil, and 80% of TSS with a d50 = 125-micron gradation. Based on the full buildout conditions of the Fowler Corridor, the specified unit will adequately treat the design storm flow rate of 1.14 CFS and allow bypass of the 25-year peak flow rate of 6.64 CFS. This unit was oversized and is capable of treating a SWQ flow rate up to 1.6 cfs. In the interim, this facility will be oversized for the expected flows, and will actually provide improved treatment of the stormwater quality volume until the full buildout condition. Interim LID Ponds – Fowler Lane The eastern portion of the Fowler ROW frontage of the BRB property during the 38’ TBC-TBC configuration shall be treated using LID stormwater ponds. These ponds are designed with sufficient capacity to treat the 10-yr storage volume expected and include an overflow pipe which feeds into the trunk stormwater main and hydrodynamic separator. Stormwater shall be collected using curb cuts and a curbed conveyance channel. A curbed sediment trap area shall be installed at the outfall to the concrete channel to provide a preferred location for sediment deposition for ease of maintenance. These LID ponds shall be stabilized using a drought-resistant grass mixture as specified on the plans and shall be protected from scour after installation by using straw matting. _________________________________________________________________________ Page 7 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Installation of these LID storm ponds provides capture volume the design storm and will reduce flow received by Fowler Lane. The pre-development condition of Fowler Lane along the property frontage with a 24-foot gravel surface was estimated to discharge approximately 1.21 cfs during the 25-year conveyance design storm. The post-development discharge for the 38-ft asphalt and curb section for Fowler Lane was estimated to be 1.05 cfs. LID Ponds – Kurk Drive LID ponds were incorporated at the east end of Kurk Drive to capture runoff east of the intersection with Buffalo Run Avenue as subsurface treatment was unfeasible due to groundwater levels and the requirement to tie into the existing asphalt section grades at the Meadow Creek Subdivision’s west boundary. These LID ponds shall include a rip-rap inlet section and shall include a section of landscape rock in the main basin area that provides additional storage. The intent is for these LID ponds to be low maintenance and not require irrigation. 5.2 Design Storm Analyses Storm water runoff analyses were performed using the Rational Method. The analyses included evaluations of the 10-year, 2-hour design storm for sizing of retention facilities and the 25-year design storm recurrence interval for inlet and piping system design. Calculations were performed using excel spreadsheets for time of concentration, peak flows, retention volumes, pipe flows, velocities, and inlet gutter spread calculations. Bentley Flowmaster software was also used to evaluate pipe capacity and velocity. Detailed calculations are included in Appendix C. For the Hydrodynamic separator, the water quality volume of 0.5 inches was used by the manufacturer to design a facility that meets the State of Montana’s requirement for stormwater treatment for a Type II 24-hr storm. 5.3 Storm Drain Capture and Conveyance The storm drain piping system for the proposed development is designed to have maximum reliability of operation, minimal maintenance requirements, and to ensure that inlets function to their design capacities while meeting necessary area drainage requirements. The 25-year design storm has been selected as the basis for design for these conveyance facilities as that is the City of Bozeman requirement from the Design Standards and Specifications Policy (Standards). Time of concentrations for each sub-basin were calculated using the TR-55 method. These time of concentration values were used to calculate peak flows for the 25-year storm and size conveyance facilities. Time of concentration calculations are included in Appendix C. Inlets were placed at all low points in the curb line and at required intervals to limit gutter flow depth to 0.15’ below the top of the curb (spread widths less than 9.5 feet). Inlets and pipes were designed to convey peak flows from a 25-year design storm. A summary spreadsheet for each sub-basin is provided in Appendix C for each inlet. A summary table is provided below for quick reference: _________________________________________________________________________ Page 8 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Table 2: Basin Peak Flow and Capture Summary Sub- basin Basin Peak Flow (cfs) Runon (cfs) Comb. Peak Flow (cfs) Capture Facility # of Inlets Spread @ Upstr. of Capt. Facility (ft) Capt. Flow (cfs) Byp. Flow (cfs) Bypass Dest. F-West 1.02 0.00 1.02 INLET - GRADE 1 4.77 0.75 0.26 F-West- bypass F-West- bypass 0.03 0.26 0.29 INLET - GRADE 1 2.60 0.27 0.02 OFFSITE F-2.1 0.21 0.00 0.21 CURB CUT 1 2.15 0.21 0.00 F-2.2 F-2.2 0.25 0.00 0.25 CURB CUT 1 2.39 0.24 0.01 F-2.3 F-2.3 0.39 0.00 0.39 CURB CUT 1 3.04 0.35 0.04 F-2.4 F-2.4 0.26 0.00 0.26 CURB CUT 1 2.46 0.25 0.01 OFFSITE K-NW 0.47 0.00 0.47 INLET - GRADE 1 3.14 0.42 0.06 OFFSITE K-NW- BYPASS 0.04 0.06 0.09 INLET - GRADE 1 0.00 0.09 0.00 OFFSITE K-SW 0.56 0.00 0.56 INLET - GRADE 1 3.40 0.47 0.08 OFFSITE K-SW- BYPASS 0.03 0.08 0.11 INLET - GRADE 1 0.00 0.11 0.00 OFFSITE K-0 0.32 0.00 0.32 INLET - SAG 1 2.43 0.32 0.00 NONE K-1 0.47 0.00 0.47 INLET - SAG 1 3.15 0.47 0.00 NONE K-2 0.66 0.00 0.66 INLET - SAG 1 3.61 0.66 0.00 NONE K-3 0.90 0.00 0.90 INLET - SAG 1 4.45 0.90 0.00 NONE K-4 0.40 0.00 0.40 INLET - SAG 1 2.90 0.40 0.00 NONE K-5 0.68 0.00 0.68 INLET - SAG 1 4.11 0.68 0.00 NONE K-6 0.28 0.00 0.28 INLET - GRADE 1 2.37 0.27 0.01 OFFSITE KC-1 0.46 0.44 0.90 INLET - GRADE 1 5.02 0.69 0.22 OFFSITE B-1 1.01 0.00 1.01 INLET - GRADE 1 5.19 0.75 0.26 B-3 B-2 0.63 0.00 0.63 INLET - GRADE 1 4.20 0.52 0.11 B-4 _________________________________________________________________________ Page 9 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Table 2: Basin Peak Flow and Capture Summary Sub- basin Basin Peak Flow (cfs) Runon (cfs) Comb. Peak Flow (cfs) Capture Facility # of Inlets Spread @ Upstr. of Capt. Facility (ft) Capt. Flow (cfs) Byp. Flow (cfs) Bypass Dest. B-3 0.81 0.26 1.07 INLET - SAG 1 5.01 1.07 0.00 NONE B-4 0.87 0.12 0.98 INLET - SAG 1 4.72 0.98 0.00 NONE C-1 1.23 0.00 1.23 INLET - GRADE 1 5.69 0.87 0.36 C-3 C-2 0.59 0.00 0.59 INLET - GRADE 1 4.13 0.49 0.11 C-4 C-3 0.83 0.36 1.18 INLET - GRADE 1 5.67 0.85 0.33 KC-1 C-4 0.51 0.10 0.61 INLET - GRADE 1 4.26 0.50 0.11 KC-1 PF-1A 2.34 0.00 2.34 INLET - SAG 2 11.40 2.34 0.00 NONE PF-1B 2.07 0.00 2.07 INLET - SAG 2 14.89 2.07 0.00 NONE PF-2 3.69 0.00 3.69 INLET - SAG 3 18.69 3.69 0.00 NONE PF-3A 4.11 0.00 4.11 INLET - SAG 3 22.44 4.11 0.00 NONE PF-3B 4.12 0.00 4.12 INLET - SAG 3 25.02 4.12 0.00 NONE PF-4A 3.30 0.00 3.31 INLET - SAG 4 19.84 3.31 0.00 NONE PF-4B 3.94 0.00 3.94 INLET - SAG 4 21.68 3.94 0.00 NONE PF-M1 0.65 0.00 0.65 INLET - GRADE 1 9.23 0.59 0.07 PF-M2 PF-M2 0.15 0.06 0.21 INLET - GRADE 1 6.09 0.21 0.00 PF-4A P-1 1.54 0.00 1.54 N/A N/A N/A N/A N/A NONE D-1 0.31 0.00 0.31 N/A N/A N/A N/A N/A NONE X-1 0.48 0.00 0.48 N/A N/A N/A N/A N/A OFFSITE X-2N 0.26 0.00 0.26 INLET - SAG 1 0.00 0.26 0.00 NONE X-2S 0.23 0.00 0.23 INLET - SAG 1 0.00 0.23 0.00 NONE Fowler- PreDev 1.21 0.00 1.21 N/A N/A N/A N/A N/A NONE ________________________________________________________________________ Page 10 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Storm drain piping was designed to have a minimum velocity of 3.0 feet per second (fps) at the design depth of flow, or when flowing full, to prevent sediment deposits. Due to the minimum storm main and lateral sizing requirements in the city, some basins do not have sufficient inflow to achieve 3.0 fps during the 25-year design storm at the beginning of the reaches. Slopes were increased as much as feasible to increase velocities while maximizing cover depths at the required minimum pipe sizes. Due to the high groundwater at the site, the minimum cover depth per the COB Standards could not be met, however the piping selected has been designed with adequate cover to meet HS-20 loading requirements (or equivalent HL-93 loading). Piping crossing major traffic areas is proposed to be made of reinforced concrete. A list of conveyance pipes proposed for the site is included below. Table 3: Pipe Conveyance Summary Table Pipe Name Pipe Diameter (in) Pipe Slope (%) 25-yr Storm Peak Design Flow (cfs) Capacity of Pipe @ 0.75 d/D Flow Scenario (cfs) Basins Contributing K-NW-1 12 0.50 0.42 2.99 K-NW K-NW-Lateral 15 0.50 0.51 5.41 K-NW, K-NW-Bypass K-SW-1 15 0.50 0.98 5.41 K-NW, K-NW-Bypass, K-SW K-SW-2 15 0.50 1.09 5.41 K-NW, K-NW-Bypass, K-SW, K-SW-Bypass F-West- Bypass 12 0.50 0.27 2.99 F-West-Bypass F-West- Lateral 15 0.50 1.02 5.41 F-West, F-West-Bypass Fowler-South 18 1.50 1.02 15.25 F-West, F-West-Bypass Fowler-North 18 1.50 2.11 15.25 K-NW, K-NW-Bypass, K-SW, K-SW-Bypass, F-West, F- West-Bypass R-1 Lateral 12 0.30 0.32 1.78 K-0 R-1.1 15 0.30 0.79 4.19 K-0, K-1 R-1.2 15 0.30 0.79 4.19 K-0, K-1 B-3 Lateral 12 0.30 1.07 1.78 B-3 B-4 Lateral 12 0.30 0.98 1.78 B-4 R-2.1 15 0.30 2.05 3.23 B-3, B-4 R-2.2 15 0.30 2.05 4.19 B-3, B-4 K-2 Lateral 12 0.30 0.66 1.78 K-2 R-2.3 15 0.30 2.71 3.23 B-3, B-4, K-2 R-2.4 15 0.30 3.61 4.19 B-3, B-4, K-2, K-3 K-4 Lateral 12 0.30 0.40 1.78 K-4 ________________________________________________________________________ Page 11 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Table 3: Pipe Conveyance Summary Table Pipe Name Pipe Diameter (in) Pipe Slope (%) 25-yr Storm Peak Design Flow (cfs) Capacity of Pipe @ 0.75 d/D Flow Scenario (cfs) Basins Contributing R-3.1 15 0.30 1.08 3.23 K-4, K-5 R-3.2 15 0.30 1.08 4.19 K-4, K-5 B-1 Lateral 12 0.50 0.75 2.30 B-1 R-4.1 12 0.50 1.27 2.99 B-1, B-2 C-2 Lateral 12 0.30 0.49 2.31 C-2 R-5.1 12 0.30 1.36 2.31 C-1, C-2 C-3 Lateral 12 0.75 0.85 3.66 C-3 R-6.1 12 0.75 1.35 3.66 C-3, C-4 K-6 Lateral 12 0.30 0.69 1.78 K-6 R-6.2 12 0.30 0.96 2.31 K-6, KC-1 PF-2 15 0.40 3.69 3.73 PF-2 PF-3A 15 0.50 4.11 4.17 PF-3A PF-3B 15 0.50 4.12 4.17 PF-3B PF-M.1 12 0.50 0.59 2.99 PF-M1 PF-M.2 12 1.00 0.80 4.22 PF-M2 5.4 Storm Water Treatment Facilities Most stormwater treatment will be performed using subsurface Stormtech® systems. An existing pond will provide treatment for a small portion of the site that currently drains to it. Additionally, a small depression will serve as a stormwater retention area for a portion of the southwest part of the site. LID ponds shall be used in areas described above, and a hydrodynamic separator shall treat some stormwater from Fowler Lane and the westernmost portion of Kurk Drive. These facilities are further described below. Road Corridor Treatment Storm runoff from internal roads is captured in separate stormwater treatment facilities designated with an “R-“. These facilities will have easements associated with each for access and maintenance by the City of Bozeman. Storm facilities R-4 and R-5 shall have vehicular access using the proposed pedestrian ramps which have been oversized to have a 12-foot width. Facility R-6 shall be provided via the concrete boulevard section and proposed sidewalk. These facilities were designed to capture 100% of the 10-year design storm volume and are located above seasonally high groundwater. ________________________________________________________________________ Page 12 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Living Unit Facility Treatment Treatment of stormwater from interior buildings, lawns, and parking shall be performed using treatment facilities beneath parking lots proposed for those dwelling units. These facilities will be owned and maintained by the property owner in accordance with the operation and maintenance manual. These facilities were designed to capture 100% of the 10-year design storm volume and are located above seasonally high groundwater. Hydrodynamic Separator Unit A hydrodynamic separation treatment unit is proposed to be installed near the end of the proposed 18” storm trunk main, at the intersection of Kurk Drive and Fowler Lane. This unit shall initially receive flows from the east side of Fowler Lane and the west end of Kurk Drive and is designed to treat the initial stormwater quality volume while providing means of bypassing the 25-year City of Bozeman design storm. The hydrodynamic separator was designed in coordination with Contech Engineered Solutions LLC and was sized with sufficient capacity to treat the stormwater quality volume for the full buildout condition for the Fowler Corridor with the 62’ road section and 100’ ROW. The CDS 2020-5 unit specified treats the stormwater quality volume of 0.5 inches and was designed by the manufacturer to meet the State of Montana’s requirements to remove trash, oil, and 80% of TSS with a d50 = 125-micron gradation. Treatment is accomplished using a combination of vortex action and screening to remove stormwater pollutants including sediment, oil/hydrocarbons, and trash and debris. Debris and sediment are captured within a sump which shall be evacuated using a vacuum truck periodically. Eastern Fowler Lane LID Basins The eastern portion of the ROW within the current 38’ TBC-TBC configuration will be performed using a series of LID stormwater ponds. Stormwater shall be collected using curb cuts and a curbed conveyance channel. A curbed sediment trap area shall be installed at the outfall to the concrete channel to provide a preferred location for sediment deposition for ease of maintenance. These LID ponds shall be stabilized using a drought-resistant grass mixture as specified on the plans and shall be protected from scour after installation by using straw matting. These facilities were designed to capture 100% of the 10-year design storm volume and are located above seasonally high groundwater. The LID stormwater basins have very mild slopes to minimize danger to the public. The stormwater basins were limited in length due to the proposed running slope of the road. This resulted in a series of shallow depressions within the east boulevard that treat stormwater runoff from the proposed road surface and surrounding landscape and pedestrian facilities within the right-of-way. An overflow drain has been provided to convey water to the 18” trunk storm main which conveys water to the hydrodynamic separator unit. ________________________________________________________________________ Page 13 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Kurk Drive LID Basins Due to the existing high groundwater and grading constraints near the tie-in point at the east end of Kurk Drive (east of the intersection of Buffalo Run Avenue), capture and treatment of stormwater east of the last inlets on Kurk Drive is being proposed using a series of Low-Impact- Design (LID) stormwater ponds. These LID basins are designed to capture and treat the initial stormwater facility volume for Basins X-2N and X-2S and are maximized to the extent possible to provide volume to treat the 10-year storm event. A sag in the road section shall prevent water from leaving the site during the design storm. Park Area The park runoff coefficient is proposed to decrease for the post-development condition and the time of concentration will remain similar to pre-development condition the area will be planted and maintained with denser grasses than the current pasture. No facility is required for the park since there will be less runoff during the post-development condition. A summary table for the park is included below. Table 4: Pre- and Post-Development Summary for Park EAST PARK Sub-basin Area (acres) Runoff Coefficient Tc (min) Stormwater Discharge Volume during 10-yr Storm (ft3) Treatment Facility Treatment Facility Type Pre-Development Park- PreDev 1.96 0.20 27.87 1,169.28 NONE NONE Post-Development Park 1.96 0.17 48.80 1,016.40 NONE NONE NOTE: There is a net decrease in stormwater discharge during the 10-yr, 2-hr design storm due to installation of denser grasses that overall decrease the runoff coefficient for the area. The addition of impervious areas is included in this calculation but is offset by the amount of dense grasses which decrease the imperviousness. Design Storm and Treatment All treatment facilities were designed to store runoff from a 10-year 2-hour storm event. See the tables below for treatment areas, storage volumes, and elevations. Exhibit B is provided to illustrate post-development drainage basins and their designated treatment facilities. Treatment facilities were designed with bottom elevations above the seasonal-high groundwater level. Proposed elevations of treatment structures and estimated high groundwater elevations are specified in Table 5 below. High groundwater elevations are based on data collected at monitoring wells for the project (Appendix B). ________________________________________________________________________ Page 14 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Table 5: Storm Basin Summary Sub- basin Area (acres) Runoff Coefficient First 1/2" Facility (ft3) Retention Storage (ft3) Treatment Facility Treatment Facility Type F-West 0.27 0.90 438.30 718.81 CDS HYDRODYNAMIC F-West- bypass 0.01 0.90 13.13 21.53 CDS HYDRODYNAMIC F-2.1 0.18 0.51 169.35 277.73 F-2.1 L.I.D. BASIN F-2.2 0.24 0.47 202.02 331.31 F-2.2 L.I.D. BASIN F-2.3 0.41 0.42 313.58 514.28 F-2.3 L.I.D. BASIN F-2.4 0.23 0.50 213.33 349.85 F-2.4 L.I.D. BASIN K-NW 0.16 0.75 212.41 348.35 CDS HYDRODYNAMIC K-NW- BYPASS 0.01 0.75 15.47 25.37 CDS HYDRODYNAMIC K-SW 0.22 0.75 300.75 493.23 CDS HYDRODYNAMIC K-SW- BYPASS 0.01 0.75 13.75 22.55 CDS HYDRODYNAMIC K-0 0.15 0.65 178.02 291.95 R-1 STORMTECH K-1 0.21 0.65 252.58 414.23 R-1 STORMTECH K-2 0.36 0.65 423.45 694.45 R-2 STORMTECH K-3 0.56 0.60 605.53 993.06 R-2 STORMTECH K-4 0.20 0.65 232.05 380.56 R-3 STORMTECH K-5 0.33 0.70 419.85 688.56 R-3 STORMTECH K-6 0.09 0.75 122.19 200.39 R-6 STORMTECH KC-1 0.22 0.70 282.48 463.27 R-6 STORMTECH B-1 0.36 0.75 490.44 804.32 R-4 STORMTECH B-2 0.34 0.75 456.91 749.33 R-4 STORMTECH B-3 0.44 0.65 523.03 857.77 R-2 STORMTECH B-4 0.43 0.68 533.18 874.41 R-2 STORMTECH C-1 0.51 0.75 688.34 1128.88 R-5 STORMTECH C-2 0.27 0.75 363.84 596.70 R-5 STORMTECH C-3 0.43 0.70 551.31 904.15 R-6 STORMTECH C-4 0.28 0.70 350.09 574.14 R-6 STORMTECH PF-1A 0.62 0.90 1008.26 1653.55 S-1A STORMTECH PF-1B 0.70 0.85 1086.37 1781.65 S-1B STORMTECH PF-2 1.41 0.90 2301.49 3774.44 S-2 STORMTECH PF-3A 1.60 0.80 2318.87 3802.94 S-3A STORMTECH PF-3B 1.83 0.85 2820.09 4624.94 S-3B STORMTECH ________________________________________________________________________ Page 15 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Table 5: Storm Basin Summary Sub- basin Area (acres) Runoff Coefficient First 1/2" Facility (ft3) Retention Storage (ft3) Treatment Facility Treatment Facility Type PF-4A 1.93 0.80 2804.33 4599.11 S-4A STORMTECH PF-4B 2.38 0.80 3459.33 5673.31 S-4B STORMTECH PF-M1 0.25 0.80 360.63 591.44 S-M STORMTECH PF-M2 0.04 0.95 67.45 110.62 S-M STORMTECH P-1 1.14 0.70 1446.03 2371.48 POND DEPRESSION D-1 0.49 0.90 798.00 1308.72 DEPRESSION DEPRESSION X-1 0.20 0.65 238.17 390.60 N/A N/A X-2N 0.11 0.65 127.02 208.31 LID-K-N L.I.D. BASIN X-2S 0.13 0.65 147.82 242.43 LID-K-S L.I.D. BASIN Park 1.98 0.18 660.82 1083.74 N/A N/A Table 6: Treatment Facility Summary Treatment Facility Type Retention Volume Required (cf) Retention Volume Provided (cf) R-1 STORMTECH 706 848 R-2 STORMTECH 3,764 4,412 R-3 STORMTECH 1,069 1,336 R-4 STORMTECH 1,210 1,463 R-5 STORMTECH 1,291 1,454 R-6 STORMTECH 901 929 S-1A STORMTECH 1,654 1,732 S-1B STORMTECH 1,782 1,857 S-2 STORMTECH 3,774 3,899 S-3A STORMTECH 3,803 3,982 S-3B STORMTECH 4,625 4,722 S-4A STORMTECH 4,600 4,901 S-4B STORMTECH 5,673 5,800 S-M STORMTECH 642 710 F-2.1 L.I.D BASIN 272 536 F-2.2 L.I.D BASIN 318 537 ________________________________________________________________________ Page 16 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Table 6: Treatment Facility Summary Treatment Facility Type Retention Volume Required (cf) Retention Volume Provided (cf) F-2.3 L.I.D BASIN 463 537 F-2.4 L.I.D BASIN 332 562 LID-K-N L.I.D BASIN 208 371 (230 surface + 141 gravel) LID-K-S L.I.D BASIN 242 254 (134 surface + 120 gravel) CDS HYDRODYNAMIC 1,326 N/A - WATER QUAL P-1 POND 2,371 12,269 D-1 DEPRESSION 1,309 2,019 Totals 42,336 55,063 ________________________________________________________________________ Page 17 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Table 7: Stormwater Facility Elevation and Groundwater Elevation Treatment Facility Bottom Elevation (ft-amsl) Estimated High Groundwater (ft-amsl) R-1 4,997.60 4,997.08 R-2 4,997.41 4,996.82 R-3 4,997.76 4,996.85 R-4 5,000.73 4,999.75 R-5 5,001.59 5,000.63 R-6 4,996.75 4,996.47 S-1A 4,996.05 4,995.75 S-1B 4,997.82 4,996.82 S-2 5,001.73 5,001.14 S-3A 5,002.31 5,001.59 S-3B 5,002.84 5,002.26 S-4A 4,998.25 4,997.23 S-4B 4,998.83 4,997.20 S-M 4,999.44 4,998.24 F-2.1 5,003.61 5,001.00 F-2.2 5,001.07 5,000.00 F-2.3 4,998.51 4,996.00 F-2.4 4,996.50 4,994.00 LID-K-N 4,997.28 4,995.78 LID-K-S 4,997.28 4,996.32 CDS N/A N/A P-1 EXISTING 4,999.06 D-1 5,001.00 5,000.50 5.5 Overflow Overflow from the Fowler Lane LID ponds shall be captured using the proposed overflow drain, conveyed via the proposed stormwater trunk main, and discharged into the Fowler Lane barrow ditch. The conveyance ditch that currently serves as an outlet to the existing onsite pond is proposed to be removed. To protect the proposed structures from damage, an outflow system is being proposed. The system includes a level control structure and Stormtech system that will provide treatment for pond effluent. This will allow the water to percolate back into the subsurface soils if available. In the event that the Stormtech system is unable to handle the peak flows, an overflow manifold and structure will be installed downstream that will allow stormwater to discharge to the proposed trunk storm main along Fowler Lane. It bears emphasizing that this outfall into the storm drain main is a backup measure and is not expected to be a frequent occurrence. Pond overflow will be conveyed through the hydrodynamic separator for treatment and discharge to the existing Fowler barrow ditch. ________________________________________________________________________ Page 18 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT 5.6 Irrigation Ditches The irrigation ditch which currently exists within the east barrow ditch of Fowler Lane is proposed to be redirected south of the property. This redirection is proposed just north of Blackwood Road and shall allow this water to be combined within an improved ditch cross section within the western side of the Fowler Lane right-of-way. This approach was determined to be preferable based on meetings with water rights owners who call water from the ditches. The ditch cross sections have been designed to ensure adequate flow is provided for the existing water rights users, plus provide additional capacity for stormwater flows expected in the ditches from the run-on basin upstream. The new west ditch shall remain combined until just south of Stucky Road where a diversion is provided to re-direct stormwater to an existing culvert that conveys water to Montana State University. Existing irrigation laterals and diversions that currently direct water to properties east of Fowler Lane will be preserved. This will require replacement of existing culverts beneath Fowler Lane. A design memo has been attached as Appendix E which details the design considerations and calculations for sizing the irrigation conveyance facilities along Fowler Lane. Conveying irrigation water within a ditch on the west side of Fowler Lane will allow water, sewer, and storm drain facilities to be installed within the proposed road corridor while maintaining required separation of facilities. Additionally, this methodology establishes the west side ditch as the future location for irrigation facilities within the Fowler corridor as development progresses. Stormwater conveyance and treatment will be located on the eastern side of the Fowler corridor and align with the City’s desire for a future regional stormwater facility to be installed in the future. The waste and seepage ditch that feeds the existing pond is proposed to be abandoned upstream of the project. Owners of BRB and the immediately adjacent upstream and downstream water rights holders for this right have expressed they do not wish to maintain the ditch since they are anticipating developing their properties. Additionally, the Middle Creek Ditch company has expressed they would prefer that this lateral be abandoned. BRB will continue coordinating a plan with the water rights owners and ditch company to divert the seepage ditch back into the Fowler Ditch where appropriate. Owners wishing to abandon their share of the waste and seepage right shall file paperwork with the state terminating water rights. BRB has been in contact with these owners and shall continue to ensure that necessary agreements and paperwork are in place prior to construction. BRB and its delegates have been coordinating with the existing irrigation ditch companies and other water rights holders that have vested water rights for the irrigation waters discussed above. Draft agreements have been provided to all vested parties, and BRB has received signed copies of the agreements from some of these. The executed agreements received so far have been provided with the submittal documents. All proposed development will maintain a minimum 50-ft setback from any designated wetland boundaries if preserving, except where mitigated through required permitting using piping or other means of conveyance. ________________________________________________________________________ Page 19 of 19 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT 6 MAINTENANCE Storm drain inlets, catch basins, and piping will be inspected at least once per year and following large storm events. Any necessary repair or maintenance should be prioritized and scheduled through the spring, summer, and fall. These items may include inspecting for any damage, removing blockages, cleaning and flushing the length of pipes, establishing vegetation on bare slopes at or near inlets, and sediment removal. Maintenance of retention basins is essential. General objectives of maintenance are to prevent clogging, standing water and the growth of weeds and wetland plants. This requires frequent unclogging of the outlets, inlets, and mowing. Removal of sediment with heavy equipment may also be necessary in 10 to 20 years. An Operation and Maintenance Manual is included in Appendix D. Fowler Lane LID ponds and hydrodynamic separator shall be maintained by the City of Bozeman. Facilities servicing the onsite public streets shall be maintained by BRB. Access easements are proposed to the City for these facilities. BRB shall be responsible for maintenance of all onsite stormwater facilities serving the parking lots and building sites. 7 CONCLUSIONS Runoff from the Buffalo Run development will be captured, conveyed, and treated according to City of Bozeman Standards with any alterations approved. The facilities are designed to provide maximum reliability of operation and minimal maintenance requirements. Access routes to any storm facilities not accessible from the road have been provided as required. Additionally, the stormwater design has considered future buildout of Fowler Lane to prevent significant reworking when the corridor is expanded in the future. Exhibit A Vicinity Map BUFFALO RUNBozeman, MontanaLand Planning 䘆 Landscape Architecture 䘆 Development Consulting475 W. 12th Avenue - Suite E - Denver, Colorado 80204-3688 - (303) 893-4288CONTEXT MAPNTSMarch 05, 2020 Exhibit B Post-Development Drainage Basins W A B C D E G F IJ K L M1 A/B 2 A/B 3 A/B 8 A/B 9 A/B 10 A/B 11 A/B 13 A/B 14 A/B 4 A/B 5 A/B 6 A/B 7 A/B 12 A/B N H O CLUBHOUSE 12S12S12S12S12S12S12S12S12S12S12S12S12S12S12S12S12S12S12S16W16W16W16W16W16W16W16W16W16W16W16W16W16W16W-2 .2 5%-1.53%-2.06%-2. 6 6 % -2.67 % D D D D D D D D D D D D D D D D SDSDSDSDSDSDSDSDSDSDSDSDSDSDSDD D D D D S-1A S-1B R-1 S-2 S-4A S-4B R-4 R-3 R-5 S-3A S-3B P-1 R-2 R-6 S-M D-1 D DD ST-POND 2022COPYRIGHT © MORRISON-MAIERLE, INC., SHEET NUMBER PROJECT NUMBER DRAWING NUMBER DATEDESCRIPTIONNO.BY \\MMI\SHARE\BOZEMAN\PROJECTS\6475\005 - BUFFALO RUN - SITE PLAN\ACAD\EXHIBITS\STORMWATER\6475.005_STORMWATER-POSTDEV.DWG PLOTTED BY:LEE HAGEMANON May/24/2022 REVISIONS DRAWN BY: DSGN. BY: APPR. BY: DATE: Q.C. REVIEW DATE: BY: 2880 Technology Blvd West Bozeman, MT 59718 406.587.0721 www.m-m.net engineers surveyors planners scientists MorrisonMaierle VERIFY SCALE AND COLOR! THIS SHEET MAY BE REDUCED AND IS INTENDED TO BE IN COLOR. THE BAR BELOW WILL MEASURE ONE INCH AT ORIGINAL DESIGN SCALE AND RED, GREEN, AND BLUE WILL BE VISIBLE IFREPRODUCED CORRECTLY. MODIFY SCALE ACCORDINGLY! THE HOMESTEAD AT BUFFALO RUN BOZEMAN MONTANA POST-DEVELOPMENT STORMWATER MAP 6475.005 EX-B LRH LRH MEE 05/2022 50 10025500 SCALE IN FEET 1.FACILITIES ARE DESIGNED AS RETENTION FOR THE REQUIRED 10-YR / 2-HR DESIGN STORM PER COB. 2.SUBSURFACE DRAINAGE FOR DOWNSPOUTS ARE NOT CURRENTLY PROPOSED. GENERAL NOTES LEGEND TREATMENT BASIN OUTLINE (COLOR VARIES) SUBBASINF2.3R-2D-1R-4R-5S-1AS-1BS-2S-3AS-3BS-4AS-4BPARKP-1R-1KURK DRIVE HOMESTEAD AVEBUFFALO RUN AVEFOWLER LANEX-105/16/2022 R-6F2.2F2.1F2.4R-3S-MCDS TREATMENT UNIT CDS X-2N X-2S Appendix B Groundwater Data [][][][][][][][][][][] E P E W W W W W DYH G G I II I I S S S I S MW MW T T W WV WV WV WV SAN MANHOLE RIM=5000.88 INV S=4989.86 INV E=4989.66 WV WV WV WV BRAWNER D I A N E L . R E V T R U S T D A T E D 0 7 / 2 3 / 1 4 C.O.S. 207 4 MEADOW C R E E K P A R T N E R S L L C MEADOW C R E E K S U B D I V I S I O N P H A S E 1 NEESE UR S U L A N12 S12 SW14 SW14 SECTIO N 2 3 T 2 S R 5 E KOUNTZ D A Y L E H . M A R I T A L T R U S T S12 SE14 SECTION 2 2 T 2 S R 5 E BRAWNER D I A N E L . R E V T R U S T D A T E D 0 7 / 2 3 / 1 4 C.O.S 1861 MW MW MW MW MW WV VERIFY SCALE! THESE PRINTS MAY BE REDUCED. LINE BELOW MEASURES ONE INCH ON ORIGINAL DRAWING. MODIFY SCALE ACCORDINGLY! 2021COPYRIGHT © MORRISON-MAIERLE, INC., SHEET NUMBER PROJECT NUMBER DRAWING NUMBER DATEDESCRIPTIONNO.BY N:\6475\005 - BUFFALO RUN - SITE PLAN\ACAD\EXHIBITS\MONITORING\6475.005_MONITORINGWELLSEXHIBIT.DWGREVISIONS DRAWN BY: DSGN. BY: APPR. BY: DATE: Q.C. REVIEW DATE: BY: 2880 Technology Blvd West Bozeman, MT 59718 406.587.0721 www.m-m.net engineers surveyors planners scientists MorrisonMaierle PLOTTED BY:LEE HAGEMAN ON Oct/14/2021 THE HOMESTEAD AT BUFFALO RUN BOZEMAN MONTANA GROUNDWATER WELL MONITORING MAP 6475.005 GW-1 LRH 10/2021 60 12030600 SCALE IN FEET GW WELL #1 GW WELL #2 GW WELL #3 GW WELL #4 GW WELL #5 NOTE: MONITORING WELLS INSTALLED BY RAWHIDE ENGINEERING ON 3/5/2020 4/6/2020 4/13/2020 4/21/2020 4/27/2020 5/4/2020 5/11/2020 5/18/2020 5/26/2020 6/3/2020 6/8/2020 6/15/2020 6/22/2020 6/29/2020 7/6/2020 7/13/2020 7/20/2020 7/27/2020 8/3/2020 8/10/2020 8/17/2020 8/24/2020 8/31/2020 9/8/2020 9/14/2020 9/21/2020 9/28/2020 10/5/2020 10/13/2020 10/20/2020 10/27/2020 11/3/2020 11/10/2020 11/17/2020 11/24/2020 12/1/2020 12/7/2020 12/14/2020 12/22/2020 12/28/202012.06 2.16 2.34 2.72 3.18 3.70 4.05 3.78 2.86 2.21 1.58 1.26 0.70 1.06 1.80 2.00 1.73 2.26 1.96 2.30 2.80 3.75 3.55 3.75 3.86 3.70 3.56 4.05 4.09 4.26 4.20 4.40 4.50 4.54 4.72 4.85 5.06 5.17 5.2222.52 2.80 2.97 3.41 3.95 4.44 4.77 4.47 3.69 2.95 2.29 1.99 1.92 2.14 2.77 2.82 2.34 3.88 2.37 3.28 3.61 3.82 4.37 3.82 4.68 4.70 4.48 4.87 4.97 5.02 4.87 5.04 5.13 5.14 5.30 5.40 5.55 5.66 5.6833.99 4.28 4.39 4.65 4.94 5.33 3.90 3.31 3.29 3.32 3.37 3.40 3.25 3.40 3.65 3.81 3.82 3.81 4.20 3.58 3.69 3.95 4.20 3.95 4.51 4.20 3.92 4.85 4.73 4.71 4.37 4.72 4.79 4.93 5.24 5.50 5.65 5.63 5.6743.18 3.37 3.50 3.84 4.27 4.68 4.68 3.78 2.44 2.38 2.17 2.05 1.65 1.80 2.33 2.63 2.68 4.12 3.22 2.48 2.43 2.84 3.74 2.84 4.18 3.28 3.53 4.43 4.40 4.65 4.44 4.90 4.86 4.93 5.20 5.40 5.60 5.73 5.7651.90 2.19 2.32 2.68 3.09 3.53 3.67 3.02 1.91 1.76 1.41 1.30 0.86 1.12 1.66 1.90 1.91 2.09 1.58 1.74 1.91 2.26 3.00 2.26 3.40 2.99 2.84 3.56 3.59 3.74 3.51 3.71 3.84 3.88 4.09 4.27 4.47 4.58 4.591/6/2021 1/12/2021 1/20/2021 1/28/2021 2/3/2021 2/12/2021 2/19/2021 2/26/2021 3/5/2021 3/12/2021 3/19/2021 3/26/2021 4/2/2021 4/9/2021 4/16/2021 4/24/2021 4/30/2021 5/7/2021 5/14/2021 5/21/2021 5/26/2021 6/2/2021 6/9/2021 6/16/2021 6/24/2021 6/30/2021 7/8/2021 7/14/2021 7/21/2021 7/28/2021 8/3/202115.33 5.39 5.44 5.55 5.63 5.72 5.77 5.66 5.66 4.59 3.27 2.96 3.06 3.19 3.44 3.76 3.83 4.1 3.62 3.81 3.48 3.28 3.36 3.03 2.26 2.46 2.66 2.74 3.56 3.91 3.8925.75 5.79 5.82 5.9 5.98 6.03 6.07 5.96 5.99 4.82 3.63 3.46 3.67 3.84 4.05 4.42 4.46 4.74 4.21 4.54 4.16 5 4.15 3.62 2.85 3.17 3.58 3.67 4.47 4.88 4.9735.91 5.97 6.09 6.28 6.36 6.49 6.53 6.49 6.51 4.7 3.41 3.61 3.91 4.36 4.57 4.89 4.8 5.29 4.75 4.07 3.65 3.28 3.54 3.44 3.57 3.47 4.00 4.12 4.33 4.58 4.4345.92 5.99 6.07 6.19 6.3 6.43 6.49 6.44 6.47 5.28 3.37 3.55 3.78 4.02 4.23 4.62 4.67 4.94 4.49 4.37 3.92 3.44 3.57 3.6 3.31 3.08 3.59 3.66 3.67 4.39 4.3754.73 4.81 4.87 4.99 5.09 5.19 5.22 5.14 5.19 3.97 2.45 2.49 2.7 2.9 3.12 3.46 3.5 3.77 3.33 3.41 4.00 2.68 2.81 2.75 2.33 2.35 2.7 2.76 3.41 3.63 3.64‐0.19 0.33 0.2‐0.08 0.33 0.77‐0.2‐0.2‐0.08‐0.82‐0.35 0.02 3.89‐0.33 0.38‐0.84 0.85 0.53 0.77‐0.32‐0.41‐0.09‐0.8‐0.41‐0.09 4.970.68 0.42 0.37‐0.26 0.1‐0.13 0.1‐0.53‐0.12‐0.21‐0.25 0.15 4.430.12 0.45 0.48‐0.13‐0.03 0.29 0.23‐0.51‐0.07‐0.01‐0.72 0.02 4.37‐0.08‐0.59 1.32‐0.13 0.06 0.42‐0.02‐0.35‐0.06‐0.65‐0.22‐0.01 3.640.04 0.198 0.306 0.05 0.198 0.424‐0.042‐0.4‐0.084‐0.498‐0.39 0.018 4.26WellDATES OF MEASUREMENT 6475.002 ‐ Buffalo Run ‐ Weekly Water Levels (FT) (Depths below Ground)Well 6475.002 ‐ Buffalo Run ‐ Weekly Water Levels (FT) (Depths below Ground)DATES OF MEASUREMENT0.000.501.001.502.002.503.003.504.004.505.005.506.006.507.003/10/2020 6/18/2020 9/26/2020 1/4/2021 4/14/2021 7/23/2021 10/31/2021Depth Below Ground (ft)DateGround Water Depth Below GroundWELL 1WELL 2WELL 3WELL 4WELL 5 Appendix C Storm Water Calculations Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Asphalt & Curb 11,688 0.268 0.90 0.241 0.90 1.10 0.99 0.99 0.266 Landscape 0 0.000 0.20 0.000 Totals 11,688 0.268 0.241 0.266 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 22.00 1.4% n/a 0.86 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 619.00 1.6% 2.69 3.84 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 5.0 min <= Sum less than 5 minutes; therefore, use time of concentration of 5 minute QRUNON:0.000 cfs QPOST‐DEV(BASIN):1.016 cfs QTOTAL:1.016 cfs Inlet Type:Combination QINTERCEPTED:0.755 cfs QBYPASS:0.261 cfs Gutter Spread Width: 4.77 ft Depth of Flow in Gutter: 2.3 in Buffalo Run | Post-Development Subbasin F-West - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 1 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Asphalt & Curb 350 0.008 0.90 0.007 0.90 1.10 0.99 0.99 0.008 Totals 350 0.008 0.007 0.008 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 22.00 1.4% n/a 0.78 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 15.00 1.6% 2.12 0.12 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 5.0 min <= Sum less than 5 minutes; therefore, use time of concentration of 5 minute QRUNON:0.261 cfs QPOST‐DEV(BASIN):0.030 cfs QTOTAL:0.291 cfs Inlet Type:Curb Only QINTERCEPTED:0.286 cfs QBYPASS:0.006 cfs Gutter Spread Width: 2.60 ft Depth of Flow in Gutter: 1.5 in Buffalo Run | Post-Development Subbasin F-West-bypass - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 2 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Asphalt & Path 3,508 0.081 0.90 0.072 0.51 1.10 0.56 0.56 0.103 Landscaped 4,536 0.104 0.20 0.021 Totals 8,044 0.185 0.093 0.103 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 58.00 2.1% n/a 12.71 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 63.34 1.6% 2.00 0.53 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 13.2 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.211 cfs QTOTAL:0.211 cfs Inlet Type:Curb Only QINTERCEPTED:0.210 cfs QBYPASS:0.000 cfs Gutter Spread Width: 2.15 ft Depth of Flow in Gutter: 1.4 in Buffalo Run | Post-Development Subbasin F-2.1 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 3 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Asphalt & Path 3,985 0.091 0.90 0.082 0.47 1.10 0.52 0.52 0.122 Landscaped 6,310 0.145 0.20 0.029 Totals 10,295 0.236 0.111 0.122 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 58.00 2.1% n/a 12.53 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 93.50 1.6% 2.06 0.76 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 13.3 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.251 cfs QTOTAL:0.251 cfs Inlet Type:Curb Only QINTERCEPTED:0.250 cfs QBYPASS:0.001 cfs Gutter Spread Width: 2.39 ft Depth of Flow in Gutter: 1.4 in Buffalo Run | Post-Development Subbasin F-2.2 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 4 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Asphalt & Path 5,690 0.131 0.90 0.118 0.42 1.10 0.47 0.47 0.190 Landscaped 12,025 0.276 0.20 0.055 Totals 17,715 0.407 0.173 0.190 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 58.00 2.1% n/a 12.53 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 93.15 1.6% 2.23 0.70 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 13.2 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.390 cfs QTOTAL:0.390 cfs Inlet Type:Curb Only QINTERCEPTED:0.362 cfs QBYPASS:0.028 cfs Gutter Spread Width: 3.04 ft Depth of Flow in Gutter: 1.7 in Buffalo Run | Post-Development Subbasin F-2.3 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 5 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Asphalt & Path 4,404 0.101 0.90 0.091 0.50 1.10 0.55 0.55 0.129 Landscaped 5,781 0.133 0.20 0.027 Totals 10,185 0.234 0.118 0.129 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 58.00 2.1% n/a 12.53 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 93.50 1.6% 2.08 0.75 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 13.3 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.265 cfs QTOTAL:0.265 cfs Inlet Type:Curb Only QINTERCEPTED:0.261 cfs QBYPASS:0.004 cfs Gutter Spread Width: 2.46 ft Depth of Flow in Gutter: 1.5 in Buffalo Run | Post-Development Subbasin F-2.4 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 6 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 6,797 0.156 0.75 0.117 0.75 1.10 0.83 0.83 0.129 Totals 6,797 0.156 0.117 0.129 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 13.50 1.5% n/a 4.10 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 184.00 2.1% 2.58 1.19 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 5.3 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.475 cfs QTOTAL:0.475 cfs Inlet Type:Combination QINTERCEPTED:0.418 cfs QBYPASS:0.058 cfs Gutter Spread Width: 3.14 ft Depth of Flow in Gutter: 1.7 in Buffalo Run | Post-Development Subbasin K-NW - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 7 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 495 0.011 0.75 0.009 0.75 1.10 0.83 0.83 0.009 Totals 495 0.011 0.009 0.009 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 13.50 1.5% n/a 4.10 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 10.00 2.1% 1.33 0.00 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 5.0 min <= Sum less than 5 minutes; therefore, use time of concentration of 5 minute QRUNON:0.058 cfs QPOST‐DEV(BASIN):0.036 cfs QTOTAL:0.093 cfs Inlet Type:Combination QINTERCEPTED:0.093 cfs QBYPASS:0.000 cfs Gutter Spread Width: 0.00 ft Depth of Flow in Gutter: N/A Buffalo Run | Post-Development Subbasin K-NW-BYPASS - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 8 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 9,624 0.221 0.75 0.166 0.75 1.10 0.83 0.83 0.182 Totals 9,624 0.221 0.166 0.182 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 20.00 1.5% n/a 5.93 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 184.00 2.1% 2.66 1.15 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 7.1 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.558 cfs QTOTAL:0.558 cfs Inlet Type:Combination QINTERCEPTED:0.475 cfs QBYPASS:0.082 cfs Gutter Spread Width: 3.40 ft Depth of Flow in Gutter: 1.8 in Buffalo Run | Post-Development Subbasin K-SW - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 9 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 440 0.010 0.75 0.008 0.75 1.10 0.83 0.83 0.008 Totals 440 0.010 0.008 0.008 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 20.00 1.5% n/a 5.93 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 10.00 2.1% 1.58 0.00 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 5.9 min QRUNON:0.082 cfs QPOST‐DEV(BASIN):0.029 cfs QTOTAL:0.111 cfs Inlet Type:Combination QINTERCEPTED:0.111 cfs QBYPASS:0.000 cfs Gutter Spread Width: 0.00 ft Depth of Flow in Gutter: N/A Buffalo Run | Post-Development Subbasin K-SW-BYPASS - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 10 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 6,573 0.151 0.65 0.098 0.65 1.10 0.72 0.72 0.108 Totals 6,573 0.151 0.098 0.108 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 20.00 1.5% n/a 5.93 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 89.00 0.3% 1.09 1.36 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 7.3 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.324 cfs QTOTAL:0.324 cfs Inlet Type:Sag QINTERCEPTED:0.324 cfs QBYPASS:0.000 cfs Gutter Spread Width: 2.43 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin K-0 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 11 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 9,326 0.214 0.65 0.139 0.65 1.10 0.72 0.72 0.153 Totals 9,326 0.214 0.139 0.153 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 20.00 1.5% n/a 5.93 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 85.00 0.3% 1.18 1.20 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 7.1 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.467 cfs QTOTAL:0.467 cfs Inlet Type:Sag QINTERCEPTED:0.467 cfs QBYPASS:0.000 cfs Gutter Spread Width: 3.15 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin K-1 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 12 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 15,635 0.359 0.65 0.233 0.65 1.10 0.72 0.72 0.257 Totals 15,635 0.359 0.233 0.257 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 23.50 1.4% n/a 6.70 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 255.00 0.6% 1.61 2.64 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 9.3 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.658 cfs QTOTAL:0.658 cfs Inlet Type:Sag QINTERCEPTED:0.659 cfs QBYPASS:0.000 cfs Gutter Spread Width: 4.99 ft Gutter Spread Width: 3.61 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin K-2 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 13 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 24,221 0.556 0.60 0.334 0.60 1.10 0.66 0.66 0.367 Totals 24,221 0.556 0.334 0.367 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 30.00 1.5% n/a 7.55 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 255.00 0.6% 1.72 2.47 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 10.0 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.900 cfs QTOTAL:0.900 cfs Inlet Type:Sag QINTERCEPTED:0.900 cfs QBYPASS:0.000 cfs Gutter Spread Width: 5.69 ft Gutter Spread Width: 4.45 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin K-3 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 14 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 8,568 0.197 0.65 0.128 0.65 1.10 0.72 0.72 0.141 Totals 8,568 0.197 0.128 0.141 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 24.00 1.5% n/a 6.63 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 134.00 0.7% 1.60 1.40 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 8.0 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.397 cfs QTOTAL:0.397 cfs Inlet Type:Sag QINTERCEPTED:0.397 cfs QBYPASS:0.000 cfs Gutter Spread Width: 3.76 ft Gutter Spread Width: 2.90 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin K-4 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 15 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 14,395 0.330 0.70 0.231 0.70 1.10 0.77 0.77 0.254 Totals 14,395 0.330 0.231 0.254 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 30.00 1.5% n/a 7.55 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 134.00 0.7% 1.78 1.25 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 8.8 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.678 cfs QTOTAL:0.678 cfs Inlet Type:Sag QINTERCEPTED:0.678 cfs QBYPASS:0.000 cfs Gutter Spread Width: 4.79 ft Gutter Spread Width: 4.11 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin K-5 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 16 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 3,910 0.090 0.75 0.067 0.75 1.10 0.83 0.83 0.074 Totals 3,910 0.090 0.067 0.074 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 15.00 1.5% n/a 0.63 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 90.00 2.1% 2.36 0.64 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 5.0 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.283 cfs QTOTAL:0.283 cfs Inlet Type:Combination QINTERCEPTED:0.271 cfs QBYPASS:0.013 cfs Gutter Spread Width: 2.37 ft Depth of Flow in Gutter: 1.4 in Buffalo Run | Post-Development Subbasin K-6 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS <= Sum less than 5 minutes; therefore, use time of concentration of 5 minutes N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 17 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 15,694 0.360 0.75 0.270 0.75 1.10 0.83 0.83 0.297 Totals 15,694 0.360 0.270 0.297 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 14.00 2.1% n/a 4.01 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 270.00 1.1% 2.31 1.95 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 6.0 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):1.017 cfs QTOTAL:1.017 cfs Inlet Type:Combination QINTERCEPTED:0.754 cfs QBYPASS:0.263 cfs Gutter Spread Width: 5.19 ft Depth of Flow in Gutter: 2.5 in Buffalo Run | Post-Development Subbasin B-1 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 18 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 14,621 0.336 0.75 0.252 0.75 1.10 0.83 0.83 0.277 Totals 14,621 0.336 0.252 0.277 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 36.00 1.0% n/a 9.47 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 231.00 1.1% 2.09 1.84 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 11.3 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.628 cfs QTOTAL:0.628 cfs Inlet Type:Combination QINTERCEPTED:0.512 cfs QBYPASS:0.116 cfs Gutter Spread Width: 4.20 ft Depth of Flow in Gutter: 2.1 in Buffalo Run | Post-Development Subbasin B-2 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 19 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 19,312 0.443 0.65 0.288 0.65 1.10 0.72 0.72 0.317 Totals 19,312 0.443 0.288 0.317 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 30.00 1.8% n/a 7.17 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 306.00 1.0% 2.30 2.22 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 9.4 min QRUNON:0.263 cfs QPOST‐DEV(BASIN):0.810 cfs QTOTAL:1.073 cfs Inlet Type:Sag QINTERCEPTED:1.073 cfs QBYPASS:0.000 cfs Gutter Spread Width: 5.01 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin B-3 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 20 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 18,818 0.432 0.68 0.294 0.68 1.10 0.75 0.75 0.323 Totals 18,818 0.432 0.294 0.323 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 25.00 1.8% n/a 6.45 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 306.00 1.0% 2.25 2.26 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 8.7 min QRUNON:0.116 cfs QPOST‐DEV(BASIN):0.866 cfs QTOTAL:0.982 cfs Inlet Type:Sag QINTERCEPTED:0.982 cfs QBYPASS:0.000 cfs Gutter Spread Width: 4.72 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin B-4 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 21 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 22,027 0.506 0.75 0.379 0.75 1.10 0.83 0.83 0.417 Totals 22,027 0.506 0.379 0.417 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 21.00 1.9% n/a 5.56 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 270.00 1.0% 2.37 1.90 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 7.5 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):1.235 cfs QTOTAL:1.235 cfs Inlet Type:Combination QINTERCEPTED:0.879 cfs QBYPASS:0.356 cfs Gutter Spread Width: 5.69 ft Depth of Flow in Gutter: 2.6 in Buffalo Run | Post-Development Subbasin C-1 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 22 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 11,643 0.267 0.75 0.200 0.75 1.10 0.83 0.83 0.221 Totals 11,643 0.267 0.200 0.221 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 28.00 1.9% n/a 6.55 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 264.00 1.0% 2.03 2.17 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 8.7 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.591 cfs QTOTAL:0.591 cfs Inlet Type:Combination QINTERCEPTED:0.487 cfs QBYPASS:0.104 cfs Gutter Spread Width: 4.13 ft Depth of Flow in Gutter: 2.1 in Buffalo Run | Post-Development Subbasin C-2 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 23 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 18,902 0.434 0.70 0.304 0.70 1.10 0.77 0.77 0.334 Totals 18,902 0.434 0.304 0.334 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 25.00 1.6% n/a 6.65 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 442.00 1.0% 2.28 3.23 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 9.9 min QRUNON:0.356 cfs QPOST‐DEV(BASIN):0.827 cfs QTOTAL:1.183 cfs Inlet Type:Combination QINTERCEPTED:0.851 cfs QBYPASS:0.332 cfs Gutter Spread Width: 5.67 ft Buffalo Run | Post-Development Subbasin C-3 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 24 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 12,003 0.276 0.70 0.193 0.70 1.10 0.77 0.77 0.212 Totals 12,003 0.276 0.193 0.212 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 23.50 1.4% n/a 6.70 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 442.00 1.0% 1.99 3.71 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 10.4 min QRUNON:0.104 cfs QPOST‐DEV(BASIN):0.508 cfs QTOTAL:0.612 cfs Inlet Type:Combination QINTERCEPTED:0.501 cfs QBYPASS:0.111 cfs Gutter Spread Width: 4.26 ft Depth of Flow in Gutter: 2.1 in Buffalo Run | Post-Development Subbasin C-4 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 25 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 9,685 0.222 0.70 0.156 0.70 1.10 0.77 0.77 0.171 Totals 9,685 0.222 0.156 0.171 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 41.00 2.1% n/a 7.92 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 102.00 1.0% 2.18 0.78 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 8.7 min QRUNON:0.443 cfs QPOST‐DEV(BASIN):0.459 cfs QTOTAL:0.903 cfs Inlet Type:Combination QINTERCEPTED:0.686 cfs QBYPASS:0.216 cfs Gutter Spread Width: 5.02 ft Depth of Flow in Gutter: 2.4 in Buffalo Run | Post-Development Subbasin KC-1 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 26 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 26,887 0.617 0.90 0.556 0.90 1.10 0.99 0.99 0.611 Totals 26,887 0.617 0.556 0.611 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 134.00 1.8% n/a 2.47 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 89.00 1.9% 2.91 0.51 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 5.0 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):2.338 cfs QTOTAL:2.338 cfs Inlet Type:Sag QINTERCEPTED:2.338 cfs QBYPASS:0.000 cfs Gutter Spread Width: 11.40 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin PF-1A - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS <= Sum less than 5 minutes; therefore, use time of concentration of 5 minutes N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 27 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 30,674 0.704 0.85 0.599 0.85 1.10 0.94 0.94 0.658 Totals 30,674 0.704 0.599 0.658 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 134.00 1.3% n/a 6.76 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 0.00 1.6% 3.12 0.00 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 6.8 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):2.077 cfs QTOTAL:2.077 cfs Inlet Type:Sag QINTERCEPTED:2.077 cfs QBYPASS:0.000 cfs Gutter Spread Width: 14.89 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin PF-1B - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 28 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 61,373 1.409 0.90 1.268 0.90 1.10 0.99 0.99 1.395 Totals 61,373 1.409 1.268 1.395 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 46.00 1.6% n/a 5.86 Shallow Concentrated Flow 321.00 0.7% 1.78 3.01 Gutter 0.00 1.6% 3.56 0.00 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 8.9 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):3.700 cfs QTOTAL:3.700 cfs Inlet Type:Sag QINTERCEPTED:3.700 cfs QBYPASS:0.000 cfs Gutter Spread Width: 18.69 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin PF-2 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 29 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 69,566 1.597 0.80 1.278 0.80 1.10 0.88 0.88 1.405 Totals 69,566 1.597 1.278 1.405 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 175.00 2.5% n/a 7.59 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 0.00 1.6% 3.66 0.00 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 7.6 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):4.118 cfs QTOTAL:4.118 cfs Inlet Type:Sag QINTERCEPTED:4.118 cfs QBYPASS:0.000 cfs Gutter Spread Width: 22.44 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin PF-3A - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 30 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 79,626 1.828 0.85 1.554 0.85 1.10 0.94 0.94 1.709 Totals 79,626 1.828 1.554 1.709 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 107.00 0.7% n/a 10.33 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 0.00 1.6% 3.65 0.00 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 10.3 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):4.109 cfs QTOTAL:4.109 cfs Inlet Type:Sag QINTERCEPTED:4.109 cfs QBYPASS:0.000 cfs Gutter Spread Width: 25.02 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin PF-3B - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 31 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 84,130 1.931 0.80 1.545 0.80 1.10 0.88 0.88 1.700 Totals 84,130 1.931 1.545 1.700 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 95.00 1.8% n/a 13.26 Shallow Concentrated Flow 158.00 1.3% 2.38 1.11 Gutter 0.00 1.6% 3.47 0.00 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 14.4 min QRUNON:0.001 cfs QPOST‐DEV(BASIN):3.309 cfs QTOTAL:3.311 cfs Inlet Type:Sag QINTERCEPTED:3.311 cfs QBYPASS:0.000 cfs Gutter Spread Width: 19.84 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin PF-4A - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 32 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 103,780 2.382 0.80 1.906 0.80 1.10 0.88 0.88 2.097 Totals 103,780 2.382 1.906 2.097 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 102.00 0.9% n/a 13.39 Shallow Concentrated Flow 221.00 1.0% 2.03 1.82 Gutter 0.00 1.6% 3.62 0.00 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 15.2 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):3.937 cfs QTOTAL:3.937 cfs Inlet Type:Sag QINTERCEPTED:3.937 cfs QBYPASS:0.000 cfs Gutter Spread Width: 21.68 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin PF-4B - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 33 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 10,819 0.248 0.80 0.199 0.80 1.10 0.88 0.88 0.219 Totals 10,819 0.248 0.199 0.219 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 169.00 2.7% n/a 6.84 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 60.00 1.8% 1.74 0.58 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 7.4 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.650 cfs QTOTAL:0.650 cfs Inlet Type:Grate Only QINTERCEPTED:0.586 cfs QBYPASS:0.063 cfs Gutter Spread Width: 9.23 ft Depth of Flow in Gutter: 1.0 in Buffalo Run | Post-Development Subbasin PF-M1 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 34 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 1,704 0.039 0.95 0.037 0.95 1.10 1.05 1.00 0.039 Totals 1,704 0.039 0.037 0.039 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 68.00 2.7% n/a 1.11 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 10.00 1.8% 1.31 0.13 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 5.0 min <= Sum less than 5 minutes; therefore, use time of concentration of 5 minute QRUNON:0.063 cfs QPOST‐DEV(BASIN):0.150 cfs QTOTAL:0.213 cfs Inlet Type:Grate Only QINTERCEPTED:0.212 cfs QBYPASS:0.001 cfs Gutter Spread Width: 6.09 ft Depth of Flow in Gutter: 0.6 in Buffalo Run | Post-Development Subbasin PF-M2 - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 35 of 43 Design Storm Frequency =25 Years PRE-DEVELOPMENT BASIN CHARACTERISTICS Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 49,578 1.138 0.60 0.683 0.60 1.10 0.66 0.66 0.751 Totals 49,578 1.138 0.683 0.751 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (%) (ft/2)(min) Sheet Flow 80.00 1.0% n/a 14.2 Shallow Concentrated Flow 60.00 1.0% 0.15 6.6 20.8 POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 49,578 1.138 0.70 0.797 0.70 1.10 0.77 0.77 0.876 Totals 49,578 1.138 0.797 0.876 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 90.00 3.6% n/a 16.92 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 16.9 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):1.537 cfs QTOTAL:1.537 cfs POST‐DEVELOPMENT FLOW RATES Buffalo Run | Post-Development Subbasin P-1 - Time of Concentration PRE‐DEVELOPMENT FLOW RATE FOR DESIGN STORM 1.154 cfs N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 36 of 43 Design Storm Frequency =25 Years PRE-DEVELOPMENT BASIN CHARACTERISTICS Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 21,280 0.489 0.20 0.098 0.20 1.10 0.22 0.22 0.107 Totals 21,280 0.489 0.098 0.107 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (%) (ft/2)(min) Sheet Flow 147.00 3.4% n/a 12.8 Shallow Concentrated Flow 0.00 0.0% 0.00 0.0 12.8 POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Impervious Building/Sidewalk 6,174 0.142 0.90 0.128 0.40 1.10 0.44 0.44 0.217 Grass 15,106 0.347 0.20 0.069 Totals 21,280 0.489 0.197 0.217 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 98.00 1.4% n/a 14.22 Shallow Concentrated Flow 110.00 1.9% 0.21 8.83 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 23.0 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.312 cfs QTOTAL:0.312 cfs POST‐DEVELOPMENT FLOW RATES Buffalo Run | Post-Development Subbasin D-1 - Time of Concentration PRE‐DEVELOPMENT FLOW RATE FOR DESIGN STORM 0.226 cfs N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 37 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 8,794 0.202 0.65 0.131 0.65 1.10 0.72 0.72 0.144 Totals 8,794 0.202 0.131 0.144 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 38.00 3.4% n/a 5.64 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 70.00 1.5% 2.26 0.52 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 6.2 min QRUNON:0.004 cfs QPOST‐DEV(BASIN):0.483 cfs QTOTAL:0.487 cfs Buffalo Run | Post-Development Subbasin X-1 - Time of Concentration POST‐DEVELOPMENT FLOW RATES N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 38 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 4,690 0.108 0.65 0.070 0.65 1.10 0.72 0.72 0.077 Totals 4,690 0.108 0.070 0.077 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 21.00 2.3% n/a 5.18 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 84.00 0.8% 1.53 0.91 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 6.1 min QRUNON:0.013 cfs QPOST‐DEV(BASIN):0.260 cfs QTOTAL:0.272 cfs Buffalo Run | Post-Development Subbasin X-2N - Time of Concentration POST‐DEVELOPMENT FLOW RATES N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 39 of 43 Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 5,458 0.125 0.65 0.081 0.65 1.10 0.72 0.72 0.090 Totals 5,458 0.125 0.081 0.090 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 52.00 2.3% n/a 8.80 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 79.00 0.8% 1.68 0.78 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 9.6 min QRUNON:0.216 cfs QPOST‐DEV(BASIN):0.226 cfs QTOTAL:0.442 cfs Buffalo Run | Post-Development Subbasin X-2S - Time of Concentration POST‐DEVELOPMENT FLOW RATES N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 40 of 43 Design Storm Frequency =25 Years PRE-DEVELOPMENT BASIN CHARACTERISTICS Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Pasture 85,557 1.964 0.20 0.393 0.20 1.10 0.22 0.22 0.432 Totals 85,557 1.964 0.393 0.432 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (%) (ft/2)(min) Sheet Flow 300.00 1.9% n/a 22.0 Shallow Concentrated Flow - Pasture 304.00 1.6% 0.87 5.8 27.9 POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Lawn 61,500 1.412 0.10 0.141 0.17 1.10 0.19 0.19 0.376 Dog Park - Grass 16,905 0.388 0.15 0.058 Concrete Basketball Court & Sidewalk 6,324 0.145 0.90 0.131 Gravel Path 828 0.019 0.60 0.011 Totals 85,557 1.964 0.341 0.376 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 300.00 1.9% n/a 20.09 Shallow Concentrated Flow - Dense Grass 324.00 1.6% 0.19 28.70 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 48.8 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):0.334 cfs QTOTAL:0.334 cfs Buffalo Run | Post-Development Subbasin PARK - Time of Concentration POST‐DEVELOPMENT FLOW RATES PRE‐DEVELOPMENT FLOW RATE FOR DESIGN STORM 0.551 cfs N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 41 of 43 Design Storm Frequency =25 Years PRE-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Gravel 15,960 0.366 0.80 0.293 0.44 1.10 0.48 0.48 0.443 Ditches / Pasture 23,940 0.550 0.20 0.110 Totals 39,900 0.916 0.403 0.443 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 24.30 32.1% n/a 2.73 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 0.00 1.6% 3.84 0.00 Trapezoid/Triangular Channel 660.00 1.5% 1.92 5.73 8.5 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):1.211 cfs QTOTAL:1.211 cfs Buffalo Run | Pre-Development Subbasin PREDEV-FOWLER - Time of Concentration PRE‐DEVELOPMENT FLOW RATES N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 42 of 43 Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Tuesday, Jan 11 2022 B-3 Combination Inlet Location = Sag Curb Length (ft) = 3.00 Throat Height (in) = 6.00 Grate Area (sqft) = 4.50 Grate Width (ft) = 1.50 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.030 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 1.07 Highlighted Q Total (cfs) = 1.07 Q Capt (cfs) = 1.07 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.40 Efficiency (%) = 100 Gutter Spread (ft) = 5.01 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Tuesday, Jan 11 2022 B-4 Combination Inlet Location = Sag Curb Length (ft) = 3.00 Throat Height (in) = 6.00 Grate Area (sqft) = 4.50 Grate Width (ft) = 1.50 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.030 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 0.98 Highlighted Q Total (cfs) = 0.98 Q Capt (cfs) = 0.98 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.29 Efficiency (%) = 100 Gutter Spread (ft) = 4.72 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Tuesday, May 17 2022 K-0 Combination Inlet Location = Sag Curb Length (ft) = 3.00 Throat Height (in) = 6.00 Grate Area (sqft) = 4.50 Grate Width (ft) = 1.50 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.030 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 0.32 Highlighted Q Total (cfs) = 0.32 Q Capt (cfs) = 0.32 Q Bypass (cfs) = -0- Depth at Inlet (in) = 1.39 Efficiency (%) = 100 Gutter Spread (ft) = 2.20 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Tuesday, May 17 2022 K-1 Combination Inlet Location = Sag Curb Length (ft) = 3.00 Throat Height (in) = 6.00 Grate Area (sqft) = 4.50 Grate Width (ft) = 1.50 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.030 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 0.47 Highlighted Q Total (cfs) = 0.47 Q Capt (cfs) = 0.47 Q Bypass (cfs) = -0- Depth at Inlet (in) = 1.62 Efficiency (%) = 100 Gutter Spread (ft) = 2.86 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Thursday, Dec 30 2021 K-2 Combination Inlet Location = Sag Curb Length (ft) = 3.00 Throat Height (in) = 6.00 Grate Area (sqft) = 4.50 Grate Width (ft) = 1.50 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.030 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 0.66 Highlighted Q Total (cfs) = 0.66 Q Capt (cfs) = 0.66 Q Bypass (cfs) = -0- Depth at Inlet (in) = 1.89 Efficiency (%) = 100 Gutter Spread (ft) = 3.61 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Thursday, Dec 30 2021 K-3 Combination Inlet Location = Sag Curb Length (ft) = 3.00 Throat Height (in) = 6.00 Grate Area (sqft) = 4.50 Grate Width (ft) = 1.50 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.030 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 0.90 Highlighted Q Total (cfs) = 0.90 Q Capt (cfs) = 0.90 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.20 Efficiency (%) = 100 Gutter Spread (ft) = 4.45 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Tuesday, May 17 2022 K-4 Combination Inlet Location = Sag Curb Length (ft) = 3.00 Throat Height (in) = 6.00 Grate Area (sqft) = 4.50 Grate Width (ft) = 1.50 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.030 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 0.40 Highlighted Q Total (cfs) = 0.40 Q Capt (cfs) = 0.40 Q Bypass (cfs) = -0- Depth at Inlet (in) = 1.52 Efficiency (%) = 100 Gutter Spread (ft) = 2.56 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Tuesday, May 17 2022 K-5 Combination Inlet Location = Sag Curb Length (ft) = 3.00 Throat Height (in) = 6.00 Grate Area (sqft) = 4.50 Grate Width (ft) = 1.50 Grate Length (ft) = 3.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.030 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 0.68 Highlighted Q Total (cfs) = 0.68 Q Capt (cfs) = 0.68 Q Bypass (cfs) = -0- Depth at Inlet (in) = 1.92 Efficiency (%) = 100 Gutter Spread (ft) = 3.68 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Dec 29 2021 PF-1A Combination Inlet Location = Sag Curb Length (ft) = 6.00 Throat Height (in) = 6.00 Grate Area (sqft) = 4.50 Grate Width (ft) = 1.50 Grate Length (ft) = 6.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.015 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 2.34 Highlighted Q Total (cfs) = 2.34 Q Capt (cfs) = 2.34 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.92 Efficiency (%) = 100 Gutter Spread (ft) = 11.40 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Dec 29 2021 PF-1B Combination Inlet Location = Sag Curb Length (ft) = 6.00 Throat Height (in) = 6.00 Grate Area (sqft) = 4.50 Grate Width (ft) = 1.50 Grate Length (ft) = 6.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.010 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 2.08 Highlighted Q Total (cfs) = 2.08 Q Capt (cfs) = 2.08 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.74 Efficiency (%) = 100 Gutter Spread (ft) = 14.89 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Friday, Oct 15 2021 PF-2 Combination Inlet Location = Sag Curb Length (ft) = 9.00 Throat Height (in) = 6.00 Grate Area (sqft) = 13.50 Grate Width (ft) = 1.50 Grate Length (ft) = 9.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.010 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 3.69 Highlighted Q Total (cfs) = 3.69 Q Capt (cfs) = 3.69 Q Bypass (cfs) = -0- Depth at Inlet (in) = 3.20 Efficiency (%) = 100 Gutter Spread (ft) = 18.69 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Dec 29 2021 PF-3A Combination Inlet Location = Sag Curb Length (ft) = 9.00 Throat Height (in) = 6.00 Grate Area (sqft) = 13.50 Grate Width (ft) = 1.50 Grate Length (ft) = 9.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.009 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 4.12 Highlighted Q Total (cfs) = 4.12 Q Capt (cfs) = 4.12 Q Bypass (cfs) = -0- Depth at Inlet (in) = 3.40 Efficiency (%) = 100 Gutter Spread (ft) = 22.44 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Wednesday, Dec 29 2021 PF-3B Combination Inlet Location = Sag Curb Length (ft) = 9.00 Throat Height (in) = 6.00 Grate Area (sqft) = 13.50 Grate Width (ft) = 1.50 Grate Length (ft) = 9.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.008 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 4.11 Highlighted Q Total (cfs) = 4.11 Q Capt (cfs) = 4.11 Q Bypass (cfs) = -0- Depth at Inlet (in) = 3.39 Efficiency (%) = 100 Gutter Spread (ft) = 25.02 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Tuesday, May 17 2022 PF-4A Combination Inlet Location = Sag Curb Length (ft) = 12.00 Throat Height (in) = 6.00 Grate Area (sqft) = 13.50 Grate Width (ft) = 1.50 Grate Length (ft) = 12.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.007 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 3.31 Highlighted Q Total (cfs) = 3.31 Q Capt (cfs) = 3.31 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.67 Efficiency (%) = 100 Gutter Spread (ft) = 19.84 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Friday, Oct 15 2021 PF-4B Combination Inlet Location = Sag Curb Length (ft) = 9.00 Throat Height (in) = 6.00 Grate Area (sqft) = 13.50 Grate Width (ft) = 1.50 Grate Length (ft) = 9.00 Gutter Slope, Sw (ft/ft) = 0.063 Slope, Sx (ft/ft) = 0.009 Local Depr (in) = -0- Gutter Width (ft) = 1.50 Gutter Slope (%) = -0- Gutter n-value = -0- Calculations Compute by: Known Q Q (cfs) = 3.94 Highlighted Q Total (cfs) = 3.94 Q Capt (cfs) = 3.94 Q Bypass (cfs) = -0- Depth at Inlet (in) = 3.31 Efficiency (%) = 100 Gutter Spread (ft) = 21.68 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Design Storm Frequency =25 Years POST-DEVELOPMENT Weighted Adjusted Runoff Runoff Runoff Frequency Coefficient Surface Area, A Area, A Coefficient Coefficient1 Factor C' = Cwd x Cf Description (ft2) (acres) C C x A Cwd Cf Cwd x Cf → Cwd x Cf ≤ 1.00 C' x A Combined Pervious/Impervious 64,750 1.486 0.77 1.145 0.77 1.10 0.85 0.85 1.259 Totals 64,750 1.486 1.145 1.259 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft) (ft/ft) (ft/2)(min) Sheet Flow 15.00 2.2% n/a 2.74 Shallow Concentrated Flow 0.00 0.0% 0.00 0.00 Gutter 1274.00 1.5% 3.42 6.22 Trapezoid/Triangular Channel 0.00 0.0% 0.00 0.00 9.0 min QRUNON:0.000 cfs QPOST‐DEV(BASIN):3.317 cfs QTOTAL:3.317 cfs Inlet Type:Combination QINTERCEPTED:1.835 cfs QBYPASS:1.484 cfs Gutter Spread Width: 7.90 ft Depth of Flow in Gutter: 3.4 in Buffalo Run | Post-Development Subbasin BlackwoodToKurkHalfofSection - Time of Concentration POST‐DEVELOPMENT FLOW RATES INLET CALCULATIONS N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 5/17/2022 1 of 1 75% Full Flow Capacity (d/D) of 18" A-2000 PVC @1.50% Project Description Manning FormulaFriction Method DischargeSolve For Input Data 0.010Roughness Coefficient %1.500Channel Slope in13.5Normal Depth in18.0Diameter Results cfs15.25Discharge ft²1.4Flow Area ft3.1Wetted Perimeter in5.4Hydraulic Radius ft1.30Top Width in16.9Critical Depth %75.0Percent Full %1.078Critical Slope ft/s10.73Velocity ft1.79Velocity Head ft2.91Specific Energy 1.808Froude Number cfs17.99Maximum Discharge cfs16.72Discharge Full %1.247Slope Full SupercriticalFlow Type GVF Input Data in0.0Downstream Depth ft0.0Length 0Number Of Steps GVF Output Data in0.0Upstream Depth N/AProfile Description ft0.00Profile Headloss %0.0Average End Depth Over Rise %75.0Normal Depth Over Rise ft/sInfinityDownstream Velocity ft/sInfinityUpstream Velocity in13.5Normal Depth in16.9Critical Depth %1.500Channel Slope %1.078Critical Slope Page 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 5/17/2022 FlowMaster[10.02.00.01]Bentley Systems, Inc. Haestad Methods Solution CenterThe Homestead at Buffalo Run_rev2.fm8 FUTURE FOWLER TRUNK MAIN Appendix D Operation and Maintenance Manual N:\6475\005 - Buffalo Run - Site Plan\04 Design\Reports\StormReport\Appendices\App-D_O&MManual\6475.005_O&MPlan.docx 1 of 4 The Homestead at Buffalo Run Storm Water Maintenance Plan May 2022 The Homestead at Buffalo Run (Buffalo Run) has a site-wide storm drainage system that is being constructed to capture, convey, and treat, storm and snowmelt runoff through the site to receiving waters, in accordance with City of Bozeman requirements. Typically, runoff collects in street gutters, enters the piped drainage system (storm drain) through curb inlets, drop inlets, manholes and culverts, and is stored and treated using underground retention and surface treatment basins. Some surface water drainage features are included for the road corridors where underground treatment was not feasible. These areas are proposed to be treated using Low Impact Development pond areas within the road boulevards which are shallow depressions and include natural vegetation for treatment. The Buffalo Run storm drain system will owned and operated by Buffalo Run Bozeman, LLC (BRB) and includes all storm drain and surface water treatment and conveyance facilities within the private property, including interior parking facilities. Systems around the site perimeter that treat runoff from internal public access and utility easements (roadways) for Kurk Drive, Homestead Avenue, and Buffalo Run Avenue, will be owned by City of Bozeman, but maintained by BRB. These public infrastructure conveyance and treatment facilities will have dedicated easements to the City of Bozeman. The following interior public road stormwater treatment facilities will be maintained by Buffalo Run Bozeman, LLC (BRB): • Facility R-1 o Kurk Drive (west of Avenue B) • Facility R-2 o Portion of Kurk Drive o North portion of Avenue B • Facility R-3 o Portion of Kurk Drive (east of midblock crossing) • Facility R-4 o Southern portion of Avenue B (south of midblock crossing) • Facility R-5 o Southern portion of Buffalo Run Avenue (south of midblock crossing) • Facility R-6 o Northern portion of Buffalo Run Avenue o Kurk Drive and Buffalo Run Avenue Intersection N:\6475\005 - Buffalo Run - Site Plan\04 Design\Reports\StormReport\Appendices\App-D_O&MManual\6475.005_O&MPlan.docx 2 of 4 • Kurk LID Ponds o East portion of Kurk (East of Buffalo Run Avenue) The following interior public road stormwater treatment facilities will be maintained by the City of Bozeman: • Fowler LID Ponds o Treats the east half of Fowler Lane along property frontage • Fowler Hydrodynamic Separator o Treats the west half of Fowler and west end of Kurk Dr up to the Fowler-Kurk Intersection  This will also treat future Fowler corridor from Blackwood Rd. to Kurk Dr. Buffalo Run Bozeman, LLC (BRB) shall maintain those storm drainage systems they are responsible for in accordance with this maintenance plan and with the applicable City of Bozeman regulations. BRB will maintain a written account of all maintenance and repair activities, such as a logbook, for future reference. Every Month, May through October 1. Grass Swales (Lawns): Mow to maintain maximum grass height of 6 inches. Do not allow mulch to discharge or accumulate within 6 feet of the flowline. 2. Storm Drain Pipe and Culverts: Trim and control vegetation near open ends of pipes to prevent any significant restriction of flow. 3. Surface Detention/Treatment Facilities: Clean the area to keep free of leaves, grass clippings, excess vegetation and debris (paper, cardboard, plastic bags, etc.). If the basin contains water at the time of inspection, return later to clean the area. If ponded water persists over a dry period of a few days, remove cover from the outlet control structure and unclog the orifice (remove debris) to ensure unimpeded flow to the outlet pipe. If sediment sump is full to the orifice level, remove all sediment from the sump. Every Three Months, and Immediately after Major Storm or Snowmelt Events 1. Grass Swales (Lawns and Native Grasses): Walk along each swale to inspect. Clean as needed to keep free of silt, debris, excess vegetation, or any other material that impedes flow. Note areas of ponding and areas with dense weeds or sparse grass cover, and repair within 1 year (see “Repair Procedures” below). 2. Storm Water Manholes and Inlets: Inspect each inlet grate and grated manhole cover. Clean as needed to keep free of leaves, debris, excess vegetation, or any other material (paper, cardboard, plastic bags, etc.) that impedes flow. In winter, ice or snow may remain over inlet grate. If water ponds excessively and creates a problem during snowmelt events, chip ice to provide a drainage channel into the manhole or inlet. 3. Surface Detention/Treatment Facilities: From November through April, continue inspection and cleaning procedures as stated under the “monthly inspection” category above, every three months and immediately after major storm or snowmelt events. N:\6475\005 - Buffalo Run - Site Plan\04 Design\Reports\StormReport\Appendices\App-D_O&MManual\6475.005_O&MPlan.docx 3 of 4 4. Underground Detention/Treatment Facilities: Open inspection port(s) in the isolator row, and view with a flashlight. If the geotextile fabric (at the bottom of the chamber) is obscured by sediment, measure depth to sediment level, and subtract from baseline depth (full depth to geotextile fabric). If the result (sediment level) is greater than 3 inches, schedule to have sediment removed, as stated under the “annual inspection” category below. Annually 1. Storm Drain Pipe (pipe terminating in manhole or inlet): Pull inlet grates and manhole covers as needed, and inspect each end of each pipe. If observed sediment level in the sump is above the lowest (discharge) pipe flowline, clean all sediment from the pipes and the manhole or inlet sump. 2. Storm Drain Pipe or Culvert (pipe terminating in open ditch or swale): If sediment has accumulated to 3 inches or more above the pipe flowline, remove sediment from the outlet pipe and ditch to provide free drainage and re-seed or sod the area of disturbance. If soil has eroded and un-vegetated rills are visible, re-seed or sod the area. If there are recurring problem areas, repair as stated in “Repair Procedures” below. 3. Underground Detention/Treatment Facilities: Remove manhole covers at each end of the isolator row. If the observed sediment level is above the lowest pipe flowline, clean all sediment from the pipes and the manhole or inlet sump. Also, look down the isolator row to see if sediment level is at or above the lower row of sidewall holes (about 3 inches above the geotextile bottom). Follow OSHA regulations for confined space entry, or use pole-mounted mirrors or cameras. If this observation or previous inspections through the inspection ports noted sediment levels greater than 3 inches, employ a pipe cleaning service to remove all sediment from the isolator row in accordance with the detention system manufacturer’s recommendations. Every 5 years 1. Surface Detention/Treatment Facilities: Sediment, windblown dust and thatch will build up over time and reduce the storage capacity. Storage capacity is the basin’s airspace volume between two elevations measured in the outlet control structure: the top of the overflow riser, and the flowline elevation of the discharge pipe. Employ a land surveyor or engineer to determine the airspace volume. If it is less than the minimum volume indicated on the approved construction drawings (record drawings), remove excess material and replace landscape materials to originally constructed conditions. Repair Procedures 1. Grass Swales with Dense Weeds or Sparse Grass Cover: Re-seed or sod the area, but first determine and address the source of the problem. Expand irrigation coverage, add soil amendments, fertilize, etc., as needed to improve growth media and grass health, and to control weeds. 2. Grass Swales, Areas of Ponding: Cut sod and re-grade the area for consistent downgradient slope along the swale. Then re-seed or sod the area of disturbance. N:\6475\005 - Buffalo Run - Site Plan\04 Design\Reports\StormReport\Appendices\App-D_O&MManual\6475.005_O&MPlan.docx 4 of 4 3. Pipe Outlet Ditch, Excessive Sediment Accumulation: Cut sod, remove sediment, and re-grade the area to a consistent downgradient slope along the outlet ditch or swale. Extend the re-grading as far as needed to provide positive drainage. Then re-seed or re-sod the area of disturbance. 4. Pipe Outlet Ditch, Erosion: It is recommended to hire a Professional Engineer to address this issue. Another option is to cut sod and re-grade the area, install a permanent, non-degradable turf reinforcement mat (TRM) per the manufacturer’s recommendations, and re-seed the area of disturbance through the TRM per the manufacturer’s recommendations. Appendix E Irrigation Ditch Information memo \\mmi\Share\Bozeman\Projects\6475\003 - Offsite Imps - Fowler and S 27th\04 Design\Reports\Irrigation Report\_sourcedocs\1_Text\6475.003_Fowler Lane Irrigation Ditch Design Memo_Relocation_202203.docx Page 1 TO: File FROM: Lee Hageman DATE: May 17, 2022 JOB NO.: 6475.003 RE: Fowler Lane Irrigation Ditch Rerouting CC: Matt Ekstrom, Matt Gagnon Urgent For Review Please Comment Please Reply For Your Use The objective of this memo is intended to summarize engineering calculations performed to ensure that sufficient irrigation and stormwater conveyance is provided for rerouting a portion of conveyance channel along Fowler Lane. Existing barrow pits are currently used as irrigation ditches to convey irrigation water owned by the Middle Creek Ditch Company, West Gallatin Canal, and private water rights to users along Fowler Lane and downstream. Rerouting of a portion of the irrigation channel on the east side of Fowler Lane is necessary to provide sufficient room to construct a 38-foot-wide City of Bozeman minor arterial road section throughout the Homestead at Buffalo Run (HBR) property frontage on Fowler Lane. The HBR property is located approximately 0.20 miles north of the Fowler Lane and Blackwood Road intersection. Existing Ditch Location and History: There are two existing barrow pits associated with Fowler Lane that also provide conveyance for irrigation water to users in the vicinity. Irrigation water originates from the point of diversion from the West Gallatin Canal located 1.7 miles south of the project site and flows within a single ditch on the west side of Fowler Lane and through a Parshall flume to provide flow measurements. After the flume, the combined irrigation water flows north in the same ditch until it reaches the south side of the Gary Cook Residence’s driveway (Lot 1 of COS 2372B). There are two culverts located at the driveway, one providing conveyance to the east (beneath Fowler), and one to the north (beneath the driveway). These culverts discharge into the barrow pits and provide conveyance for water on both sides of Fowler Lane. The water then continues north in both ditches along Fowler Lane to Stucky Road where water is conveyed through culverts and discharged north into receiving channels. Fowler Lane Irrigation Ditch Rerouting \\mmi\Share\Bozeman\Projects\6475\003 - Offsite Imps - Fowler and S 27th\04 Design\Reports\Irrigation Report\_sourcedocs\1_Text\6475.003_Fowler Lane Irrigation Ditch Design Memo_Relocation_202203.docx Page 2 Until approximately 15 years ago, irrigation water was historically conveyed solely on the west side all the way from the diversion point to Stucky Road. The ditch companies decided at that time to install a culvert beneath Fowler Lane as it was a convenient way to ensure additional flow capacity while reducing maintenance frequency. Design Flow: In order to provide sufficient irrigation water to water rights holders along Fowler Lane, research was performed to determine the amount of irrigation water required to be conveyed. Based on water rights research and conversations with the ditch rider for both ditch companies and other stakeholders, it was determined that approximately 1,000 miner’s inches (25 cubic feet per second) is required for irrigation use within the ditch. Subsequent conversations with representatives from the Middle Creek Ditch company indicated that the maximum flow observed through the Parshall Flume has actually been less than 1,000 miner’s inches described above, though these ditches must maintain capacity for that amount. Stormwater was evaluated during the design process for these ditches. Calculations were performed to ensure that a 10-year, 24-hour storm event (as required by the Montana Department of Environmental Quality’s Circular #8) could be conveyed in addition to irrigation water. A stormwater basin for the area was determined using a digital elevation model from USGS within ArcGIS. This 17.73-acre drainage basin was used as a basis for determining the stormwater flows using the rational method, as summarized below: Stormwater Calculations o Total Drainage Area Basin = 17.73 Acres  Gravel Roadway = 2.93 acres  Pastureland = 14.8 acres o Composite Rational C Coefficient of Basin = 0.299 o Calculated Storm Runoff 9.62 CFS It was determined that total conveyance for all rerouted ditch sections should be adequate to provide 25 CFS of irrigation water and 9.62 CFS of stormwater, for a total of 34.62 CFS. Fowler Lane Irrigation Ditch Rerouting \\mmi\Share\Bozeman\Projects\6475\003 - Offsite Imps - Fowler and S 27th\04 Design\Reports\Irrigation Report\_sourcedocs\1_Text\6475.003_Fowler Lane Irrigation Ditch Design Memo_Relocation_202203.docx Page 3 Ditch Capacities Existing Ditch: The existing ditch capacity varies based on location along Fowler Lane due to running slope and dimensions, but is most constrained between the Parshall flume and the Cook residence driveway. A survey was performed on the constraining section to determine the existing maximum conveyance capacity and ensure that downstream channels have adequate capacity. Minimum Ditch Capacity Specifications: - Minimum cross-sectional area of ditch: 13.5 SF - Minimum average slope of ditch: 1.4% - Average bottom width: 7.75 FT - Wetted Perimeter: 13.56 FT - Depth: 1.4 FT - Side Slopes (H:V): 1.57 (Left), 2.06 (Right) - Maximum flow (Q): 75.36 CFS - Manning’s n Value: 0.035 (natural channel with stony bottom and weedy sides) Therefore, even the most constrained existing cross section is capable of conveying over two times the 34.6 CFS design flow calculated above. Proposed Ditch: The proposed rerouting includes diverting flow from a portion of the existing eastern ditch upstream of Blackwood Road to the west beneath Fowler Lane using a culvert to create a single combined conveyance facility on the west side of Fowler Lane next to the property. The proposed rerouting culvert shall be a 42” x 29” corrugated metal arch pipe and is located approximately 530 linear feet south of the Homestead at Buffalo Run’s southern property line. The arch pipe is equivalent to a 36” round pipe and shall provide a capacity of 40 cfs when installed at the proposed 1.15% slope, therefore exceeding the 34.6 cfs capacity. The culvert shall be required to carry only the flow from the eastern ditch, not the entire design flow of 34.6 cfs; therefore, this pipe is more than adequate for conveyance of irrigation and stormwater. Fowler Lane Irrigation Ditch Rerouting \\mmi\Share\Bozeman\Projects\6475\003 - Offsite Imps - Fowler and S 27th\04 Design\Reports\Irrigation Report\_sourcedocs\1_Text\6475.003_Fowler Lane Irrigation Ditch Design Memo_Relocation_202203.docx Page 4 Culverts beneath accesses to properties along the west side of Fowler shall be upsized to 36” CMP installed at approximately 2.00% slope (flattest being 1.92%). These culverts will provide conveyance capacity of approximately 54 cfs flowing full. The proposed ditch cross section is trapezoidal in shape and was designed with similar foreslopes and backslopes as the existing ditches. This design can handle the design flow (irrigation plus stormwater) while providing a factor of safety of 1.9 in the typical section or approximately 65 cfs with a running slope of 1.5 percent. Once combined, the ditch section shall be improved from that point all the way to Stucky Road. Proposed Ditch Design Dimensions: o 2:1 (H:V) Foreslope & 1:1 (H:V) Backslope o Bottom Width: 1.5 feet o Minimum Depth: 2.3 feet o Manning’s N coefficient: 0.035 o Ditch Running Slope: 1.5% Culverts for redirection of the main channel flow plus any laterals for ditch users shall have riprap installed at the inlets and outlets to prevent erosion at these locations. Culverts are proposed to be oriented at less than 90-degree angles (45-degrees typical) when crossing Fowler Lane to improve conveyance while reducing water losses and scouring. Fowler Lane Irrigation Ditch Rerouting \\mmi\Share\Bozeman\Projects\6475\003 - Offsite Imps - Fowler and S 27th\04 Design\Reports\Irrigation Report\_sourcedocs\1_Text\6475.003_Fowler Lane Irrigation Ditch Design Memo_Relocation_202203.docx Page 5 Typical Cross Sections Representative cross sections were taken along Fowler Lane showing the existing and proposed conveyance facilities. These cross sections show the elevation of the design flow graphically and based on cross section dimensions and longitudinal flow slopes. Exhibit 1 shows the existing and proposed cross sections at two locations: - South of the HBR property (Station 2+50) - At the HBR property frontage (Station 14+00) The existing and proposed cross sections both have sufficient capacity for the required design flows while providing large factors of safety for unexpected flow scenarios. The proposed cross section was designed with similar cross sections to the extent feasible in the area available within the existing rights-of-way. Summary: The proposed rerouting design of the ditch through the City of Bozeman section of Fowler Lane and the transition sections have been designed to convey both irrigation water and anticipated stormwater runoff while providing a factor of safety for larger storm events. Relocation of the ditch to the west using the proposed cross section represents a viable long-term solution for this project as well as future projects in the Fowler Lane corridor. This methodology will allow existing irrigation users access to their water rights while minimizing future disruption to irrigation ditches users as the City of Bozeman expands along its current boundary. Attachments - Exhibit 1 (Overview Map) - Exhibit 2 (Representative Design Cross Sections) - Major Culvert Reports - Fowler Design Plans Subset o Plan and Profile Sheets LEGEND PROPOSED WEST SIDE DITCH IMPROVEMENTS FOR COMBINED FLOW ALONG COUNTY ROAD SECTIONS NEW CULVERT OF SPECIFIED SIZE (FLOW DIRECTION FROM WEST TO EAST) PROPOSED WEST SIDE DITCH OPTION THROUGHOUT PROPERTY FRONTAGE FIGURE NUMBER © PROJECT NO.DRAWN BY: DSGN. BY: APPR. BY: DATE: COPYRIGHT MORRISON-MAIERLE, INC.,2022N:\6475\003 - Offsite Imps - Fowler and S 27th\ACAD\Exhibits\6475.003_DITCH REALIGNMENT VICINITY MAP.dwg Plotted by lee hageman on May/17/2022 engineers surveyors planners scientists MorrisonMaierle 2880 Technology Blvd West Bozeman, MT 59718 406.587.0721 www.m-m.net 6475.003 EXH-1 BUFFALO RUN - OFFSITE IMPROVEMENTS BOZEMAN MONTANA FOWLER LANE IRRIGATION DITCH REALIGNMENT OVERVIEW MAP LRH LRH LRH 05/17/2022 N.T.S. BLACKWOOD ROAD STUCKY ROAD FOWLER LANEHERIZA, T H O M A S J & M A Y L HAGGER T Y F A M I L Y 2B HOLD I N G S GAVIN, W I L L I A M M B & R E N E E R BRADLEY P L A C E KOUNTZ , D A Y L E H CHRISTE N S E N , J O N & E L I Z A B E T H REAL RE D L L C KOUNTZ , D A Y L E H KOUNTZ , D A Y L E H BUFFALO RUN BOZEMAN PROPERTY TOWERS , CHRISTO P H E R R FOWLER L A N E LLC COOK REVOCA B L E TRUST COOK, JE F F E R Y W & SARA H TOWERS , CHRISTO P H E R R PRESERVE EXISTING CMP CULVERT TO EAST TO MAINTAIN WATER ACCESS TO REAL RED LLC PROPERTY PRESERVE EXISTING CMP CULVERTS UNDER STUCKY ROAD ON EACH SIDE OF FOWLER LANE NEW CULVERT TO CONVEY LOCALIZED STORM RUNOFF FROM EAST SIDE DITCH. INSTALL 15" CMP AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW NEW 36" EQUIVALENT ARCH CMP CULVERT CROSSING. INSTALL CMP AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW TO MINIMIZE ENERGY/ WATER LOSS AND MINIMIZE DEBRIS BUILDUP. ALL IRRIGATION WATER CONVEYED WEST TO COMBINED DITCH NEW 30" EQUIVALENT ARCH PIPE CMP CULVERT TO BE ANGLED AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW TO MINIMIZE ENERGY/ WATER LOSS AND MINIMIZE DEBRIS BUILDUP. CULVERT INSTALLED TO PROVIDE DIVERSION FOR MSU WATER RIGHTS NO MODIFICATIONS TO EXISTING DITCHES SOUTH OF BLACKWOOD ROAD NEW CULVERT OF SPECIFIED SIZE (FLOW DIRECTION FROM EAST TO WEST) NO MODIFICATIONS TO EXISTING CULVERTS BENEATH BLACKWOOD ROAD AT INTERSECTION BOZEMAN H A U S T W O L L C KDG HOL D I N G S L L C >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>MAINTAIN EXISTING DIVERSION FOR BRADLEY PROPERTY ===[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]======[]===2+50 -2.74%-2.98%5015501350145016501750155013501450165017501550155015STA. 2+50 5010 5020 5010 5020 0 10 20 30 400-10-20-30-40 5017.05016.871.3:1 2.4:1 2.1 :12.0:12.0 :12.1:13%3% 4% 4%3.45'1.50' 14+00 -2.06%-1.33%4996499649974997499749984997499749984998499849954995STA. 14+00 4992 5000 4992 5000 0 10 20 30 400-10-20-30-40 4998.34998.424998.04998.846% 3%2. 4 :10.9:11.50'2.30'3%2%1.0:12.0:11%5. 3 : 1 [][][][] EG T T KOUNTZ DA Y L E H . M A R I T A L T R U S T S12 SE14 SECTION 22 T 2 S R 5 E T T T T ===[]======[]======[]======[]===W UDUDUDUD UD 2022COPYRIGHT © MORRISON-MAIERLE, INC., SHEET NUMBER PROJECT NUMBER DRAWING NUMBER DATEDESCRIPTIONNO.BY \\MMI\SHARE\BOZEMAN\PROJECTS\6475\003 - OFFSITE IMPS - FOWLER AND S 27TH\ACAD\EXHIBITS\6475.003_ROAD CROSS SECTION EXHIBIT_REVISED_03-22-22.DWG PLOTTED BY:LEE HAGEMAN ON May/17/2022 REVISIONS DRAWN BY: DSGN. BY: APPR. BY: DATE: Q.C. REVIEW DATE: BY: 2880 Technology Blvd West Bozeman, MT 59718 406.587.0721 www.m-m.net engineers surveyors planners scientists MorrisonMaierle VERIFY SCALE AND COLOR! THIS SHEET MAY BE REDUCED AND IS INTENDED TO BE IN COLOR. THE BAR BELOW WILL MEASURE ONE INCH AT ORIGINAL DESIGN SCALE AND RED, GREEN, AND BLUE WILL BE VISIBLE IFREPRODUCED CORRECTLY. MODIFY SCALE ACCORDINGLY! BUFFALO RUN SUBDIVISION OFFSITE IMPROVEMENTS BOZEMAN MONTANA FOWLER LANE PROPOSED DESIGN CROSS SECTIONS 6475.003 1 EXH-2 LRH LRH MEE 05/2022 PROPOSED CITY SECTION EXISTING GROUND PROPOSED ROAD & DITCH SECTION EXISTING GROUND PROPOSED IRRIGATION DITCH EXISTING IRRIGATION DITCH PROPOSED IRRIGATION DITCH EXISTING IRRIGATION DITCH FOWLER LANE STATION 2+50 FOWLER LANE STATION 14+00 PROPOSED DITCH REQUIRED CAPACITY LEVEL AT DESIGN FLOW OF 35 CFS 1.35'PROPOSED DITCH REQUIRED CAPACITY LEVEL AT DESIGN FLOW OF 35 CFS BLACKWOOD ROAD FOWLER LANEHOMEST E A D A T BUFFALO R U N FUTURE KURK DRIVE 100 200501000 SCALE IN FEET 0 VERT. SCALE IN FEET 0 HORIZ. SCALE IN FEET 12 2 4 510 10 20 1.72'0 VERT. SCALE IN FEET 0 HORIZ. SCALE IN FEET 12 2 4 510 10 20 PROPOSED CULVERT AT 45° FROM EAST TO WEST 62 LF OF 42 X 29 ARCH CMP @ 1.15% PROPOSED CULVERT AT 45° FROM EAST TO WEST 62 LF OF 42 X 29 ARCH CMP @ 1.15% PROPOSED CULVERT AT 45° FROM EAST TO WEST FOR ISOLATED AREAS DRAINING TO NORTH THAT WILL NOT DRAIN WITH LARGER CULVERT NEAR BLACKWOOD ~70 LF OF 15"Ø CMP @ 1.25% PLUG AND ABANDON OR REMOVE EXISTING CULVERT PRESERVE EXISTING CULVERT IF POSSIBLE OR RE-INSTALL AT REQUIRED ELEVATIONS FOR DRAINAGE TO NORTH REPLACE EXISTING CULVERT WITH NEW 18" CMP FULL FLOW CAPACITY: 65 CFS (2,600 MINER'S INCHES) WITH 1.5% RUNNING SLOPE PROPOSED EDGE OF ASPHALT (TYP,) PROPOSED TOP BACK CURB (TYP,) EXISTING EDGE OF GRAVEL ROAD PROPOSED EDGE OF GRAVEL ROAD Culvert Calculator Report Fowler-MSUArch-35x24 Title: 27th - Buffalo Run n:\...\culvertmaster\27thave-proposedculverts.cvm 05/16/22 12:18:30 PM Morrison Maierle Inc © Bentley Systems, Inc. Haestad Methods Solution Center Watertown, CT 06795 USA +1-203-755-1666 Project Engineer: lhageman CulvertMaster v3.3 [03.03.00.04] Page 1 of 1 Solve For: Discharge Culvert Summary Allowable HW Elevation 4,934.81 ft Headwater Depth/Height 1.55 Computed Headwater Eleva 4,934.81 ft Discharge 10.41 cfs Inlet Control HW Elev. 4,934.81 ft Tailwater Elevation 4,931.09 ft Outlet Control HW Elev. 4,933.19 ft Control Type Inlet Control Grades Upstream Invert 4,931.72 ft Downstream Invert 4,931.09 ft Length 63.50 ft Constructed Slope 1.274331 ft/ft Hydraulic Profile Profile S2 Depth, Downstream 0.24 ft Slope Type Steep Normal Depth 0.24 ft Flow Regime Supercritical Critical Depth 0.84 ft Velocity Downstream 23.29 ft/s Critical Slope 0.011841 ft/ft Section Section Shape Arch Mannings Coefficient 0.022 Section MaterialSteel and Aluminum Var CR Span 2.92 ft Section Size 35 x 24 inch Rise 2.00 ft Number Sections 1 Outlet Control Properties Outlet Control HW Elev. 4,933.19 ft Upstream Velocity Head 0.37 ft Ke 0.70 Entrance Loss 0.26 ft Inlet Control Properties Inlet Control HW Elev. 4,934.81 ft Flow Control Unsubmerged Inlet Type Mitered to slope (arch) Area Full 4.5 ft² K 0.03000 HDS 5 Chart 34 M 1.00000 HDS 5 Scale 2 C 0.04630 Equation Form 1 Y 0.75000 Culvert Calculator Report Fowler-SouthDiversion-42x29 Title: 27th - Buffalo Run n:\...\culvertmaster\27thave-proposedculverts.cvm 05/16/22 12:17:58 PM Morrison Maierle Inc © Bentley Systems, Inc. Haestad Methods Solution Center Watertown, CT 06795 USA +1-203-755-1666 Project Engineer: lhageman CulvertMaster v3.3 [03.03.00.04] Page 1 of 1 Solve For: Discharge Culvert Summary Allowable HW Elevation 5,015.60 ft Headwater Depth/Height 1.49 Computed Headwater Eleva 5,015.60 ft Discharge 40.25 cfs Inlet Control HW Elev. 5,015.60 ft Tailwater Elevation 5,011.29 ft Outlet Control HW Elev. 5,015.15 ft Control Type Inlet Control Grades Upstream Invert 5,012.01 ft Downstream Invert 5,011.29 ft Length 62.00 ft Constructed Slope 0.011613 ft/ft Hydraulic Profile Profile M2 Depth, Downstream 1.68 ft Slope Type Mild Normal Depth 2.01 ft Flow Regime Subcritical Critical Depth 1.68 ft Velocity Downstream 7.64 ft/s Critical Slope 0.016076 ft/ft Section Section Shape Arch Mannings Coefficient 0.022 Section MaterialSteel and Aluminum Var CR Span 3.50 ft Section Size 42 x 29 inch Rise 2.42 ft Number Sections 1 Outlet Control Properties Outlet Control HW Elev. 5,015.15 ft Upstream Velocity Head 0.69 ft Ke 0.70 Entrance Loss 0.49 ft Inlet Control Properties Inlet Control HW Elev. 5,015.60 ft Flow Control Transition Inlet Type Mitered to slope (arch) Area Full 6.5 ft² K 0.03000 HDS 5 Chart 34 M 1.00000 HDS 5 Scale 2 C 0.04630 Equation Form 1 Y 0.75000 March 18, 2022 Middle Creek Ditch Company 5100 Patterson Road Bozeman, MT 59718 RE: Agreement for Relocation of the Middle Creek Ditch along Fowler Lane Dear Middle Creek Ditch Company Board: In April of 2021, the Homestead at Buffalo Run project was approved by the City of Bozeman for annexation into the City with a R4 zoning classification. Currently, the project is going through the final stages of Site Plan approval from the City of Bozeman. As part of the Homestead at Buffalo Run project on Fowler Lane, the City of Bozeman is requiring that Fowler Lane be widened to an approved City section for a minor arterial classification (within the property limits of the project). As a result of this requirement, the irrigation ditch that currently runs along the east side of Fowler Lane is proposed to be relocated to the west side of Fowler Lane between Stucky Road and south of Blackwood Road. During the course of designing and engineering the project, our consultant team has been in consistent communication with the ditch companies and most of the private water owners on those same ditches. Calculations and design options have been provided and comments received from multiple parties. Modifications and revisions were made to the originally proposed design as a result of the comments and concerns that were expressed. Attached is an agreement with exhibits that reflect the final proposed design. We are requesting your signature on the attached agreement reflecting that you are in agreement with the proposed design for relocation of the water to be conveyed to the west side of Fowler. Based on calculations and engineering, the amount of water received by the water owners, or the point of diversion will not change and will be the same amount of water as historically received. If you have any questions, I and/or our legal counsel will be happy to answer them for you. Below is the contact information for those parties: • Derek Williams – derek@bridgerdevelop.com, 303-887-4045 • Susan Swimley - swimley@swimleylaw.com, 406-586-5544 • Abigail Brown - abby@mtwaterlaw.com, 406-457-5494 We are requesting the fully signed and executed agreement from you by Friday April 1, 2022. Thank you so much for your time and consideration. Sincerely, Buffalo Run Bozeman, LLC Derek Williams Manager/Member Cc: Susan Swimley Abigail Brown Page 1 of 5 DITCH RELOCATION AGREEMENT This Ditch Relocation Agreement (“Agreement”) is entered into this ______ day of ____________, 2022, by and between the Middle Creek Ditch Company, a Montana corporation with address of 5100 Patterson Road, Bozeman, MT 59718, (hereinafter referred to as “the Ditch Company”) and Buffalo Run Bozeman, LLC, a Colorado limited liability company of 5400 Fowler Lane, Bozeman, MT 59718 (hereinafter referred to as “BRB”) and collectively referred to as “the Parties”. WHEREAS, the Ditch Company is the owner of an irrigation ditch system located in the southwest area of Bozeman and more particularly between Blackwood Road and Stucky Road (hereinafter referred to as the “Ditch”); WHEREAS, the Ditch Company has established a ditch easement for the Ditch for the purpose of conveying irrigation water to its members’ real property; WHEREAS, the Ditch runs parallel to Fowler Lane on both the east and west side of Fowler Lane; WHEREAS, BRB desires to relocate the east-side portions of the Ditch and improve the west-side portions of the Ditch to facilitate the improvements to Fowler Lane in accordance with approved plans required by the City of Bozeman and prepared by Morrison Maierle; and WHEREAS, the Parties are desirous of formalizing an agreement between them which will define the terms and conditions under which BRB might relocate and improve the Ditch; NOW, THEREFORE, the Parties mutually covenant and agree as follows: Page 2 of 5 1. All recitals are incorporated herein as if fully set forth. 2. The Ditch Company, subject to the terms and conditions set forth herein, shall permit BRB to relocate and improve the Ditch in accordance with approved plans prepared by Morrison Maierle and as set forth on Exhibit A attached hereto, which exhibit shall become an integral part of this Agreement. 3. Upon execution of this Agreement, the Ditch Company shall review any and all plans, specifications, and drawings prepared by BRB or any engineer, agent, contractor, or other person on behalf of BRB which specify the nature of such construction methods and materials for the relocation and improvement of the Ditch including, but not limited to, description of materials, re- grading, cleaning, clearing of vegetation, realignment, or culverts which BRB intends to construct and which will encroach upon or in any way interfere with the Ditch. BRB shall provide the aforementioned plans, specifications, and drawings to the Ditch Company as soon after execution of this Agreement as practicable. BRB acknowledges Ditch Company may hire, at BRB’s expense, a qualified, third party professional engineer to review any plans, specifications, or drawings to determine if the same, once constructed, will provide for the adequate transport of water through the Ditch without jeopardizing the integrity of the Ditch. In the event the Ditch Company shall determine the proposed relocation or improvement of the Ditch, once constructed, will not provide for the adequate transport of water through the new Ditch and/ or will jeopardize the integrity of the water conveyance, the Ditch Company shall give notice of the same, together when any other findings, to BRB within fourteen (14) days of receipt of the aforementioned plans, specifications, and drawings. BRB shall have the right to cure the issues raised by the Ditch Company. 5. During relocation and improvement of the Ditch, BRB shall be responsible for stabilizing the ditch bank around any culvert or pipeline openings so no sloughing occurs. 6. BRB agrees to reimburse Ditch Company for any and all expenses it may incur in the preparation and recording of this Agreement including, but not limited to Ditch Company staff time, reasonable attorney fees incurred by Ditch Company to review this Agreement or any and all plans, drawings, or specifications for construction work or changes which BRB undertakes pursuant to this Agreement. All fees and expenses to be paid under this Agreement shall be invoiced to BRB by the Ditch Company no later than forty-five (45) days after the expense is incurred. BRB shall pay the Ditch Company’s invoice(s) within forty-five (45) days of presentation Page 3 of 5 to BRB by Ditch Company. 7. BRB agrees the Ditch Company may enter upon the Ditch and ditch easement during construction of the new Ditch for purposes of inspection, repair, operation and maintenance of the Ditch. However, at no time shall such entry interfere with the construction of the new Ditch or the on-going operations on the Property. 8. Under no circumstances shall BRB interrupt or in any way interfere with the flow of water through the Ditch at any time without prior written consent of the Ditch Company. Permission to interrupt the flow of water will be granted based on the sole discretion of the Ditch Company, but will not be unreasonably withheld and be consistent with achieving the purpose of this Agreement. 9. Upon BRB’s completion of the relocation and improvement of the Ditch, the Ditch Company shall have the opportunity to inspect and confirm the relocated and improved Ditch operates and performs as expected. Once the Ditch Company confirms the relocated and improved Ditch operates as expected, the Parties agree BRB shall have no further obligation to inspect, maintain, or repair the new Ditch. The Ditch Company’s confirmation shall not be unreasonably withheld. 10. BRB hereby agrees to indemnify and hold the Ditch Company harmless from any and all claims, causes of action, costs, and reasonable attorney fees which the Ditch Company may sustain by reason of or in connection with any claim filed against it for any event which may occur during BRB’s relocation and improvement of the Ditch or as a result of any action by BRB, its successors, agents, assigns or property owner(s). 11. All covenants and agreements herein contained shall extend to and be binding upon the heirs, personal representatives, assigns, or successors of the respective parties hereto and shall run with the title of the property in perpetuity unless rescinded in writing by the Ditch Company. 12. This Agreement constitutes the entire agreement and understanding between the parties hereto and supersedes all prior and contemporaneous agreements and understandings of the parties in connection herewith which conflict with the expressed terms, covenants, and conditions of this Agreement. Covenant, representation, or condition not expressed in this Agreement shall not be effective to interpret, change, or restrict the express provisions of this Agreement unless specified in writing and signed by both parties hereto. Page 4 of 5 13. If it becomes necessary for either party hereto to bring suit to enforce their rights under this Agreement and if that party shall prevail in such action, the other party agrees to pay all of the costs of the action as allowed by the Court together with reasonable attorney fees. 14. Nothing in this Agreement is intended to convey any ownership interest in the water rights owned by Ditch Company nor any permission to use water conveyed in the Ditch pursuant to a water right in any manner not consistent with Montana law. BRB is expressly prohibited from seeking to change any elements of Ditch Company’s water rights without the express written consent of Ditch Company. 15. This Agreement may be signed in counterparts, paper or electronic, each of which shall constitute an original, and all of which will be collectively deemed to constitute one document. 16. The Parties represent and warrant that they have read this Agreement, and each and every part thereof; that they understand the terms and conditions; and have consulted with counsel with respect thereto; and that they accept, agree to and intend to be bound by the terms and conditions of this Agreement. IN WITNESS WHEREOF, the parties hereto have signed and sealed this Agreement the day and year above first written. MIDDLE CREEK DITCH COMPANY _________________________________ By:______________________________ Its:______________________________ STATE OF MONTANA ) : ss. COUNTY OF GALLATIN ) This instrument was acknowledged before me on _____________________2022, by ___________________, as _______________ of Middle Creek Ditch Company. ___________________________________ Notary State of Montana (seal) Printed Name: _______________________ Page 5 of 5 BUFFALO RUN BOZEMAN, LLC: __________________________________ BY:_______________________________ Its: Manager STATE OF MONTANA ) : ss. COUNTY OF GALLATIN ) This instrument was acknowledged before me on _____________________2022, by __________________, as Manager of Buffalo Run Bozeman, LLC. ___________________________________ Notary State of Montana (seal) Printed Name: _______________________ LEGEND PROPOSED WEST SIDE DITCH IMPROVEMENTS FOR COMBINED FLOW ALONG COUNTY ROAD SECTIONS NEW CULVERT OF SPECIFIED SIZE (FLOW DIRECTION FROM WEST TO EAST) PROPOSED WEST SIDE DITCH OPTION THROUGHOUT PROPERTY FRONTAGE FIGURE NUMBER © PROJECT NO.DRAWN BY: DSGN. BY: APPR. BY: DATE: COPYRIGHT MORRISON-MAIERLE, INC.,2022 N:\6475\003 - Offsite Imps - Fowler and S 27th\ACAD\Exhibits\6475.003_DITCH REALIGNMENT VICINITY MAP.dwg Plotted by lee hageman on Mar/11/2022 engineers surveyors planners scientists MorrisonMaierle 2880 Technology Blvd West Bozeman, MT 59718 406.587.0721 www.m-m.net 6475.003 EX-A BUFFALO RUN - OFFSITE IMPROVEMENTS BOZEMAN MONTANA FOWLER LANE IRRIGATION DITCH REALIGNMENT OPTION #2 LRH LRH LRH 03/11/2022 N.T.S. BLACKWOOD ROAD STUCKY ROAD FOWLER LANEHERIZA, T H O M A S J & M A Y L HAGGER T Y F A M I L Y 2B HOLD I N G S GAVIN, W I L L I A M M B & R E N E E R BRADLEY P L A C E KOUNTZ , D A Y L E H CHRISTE N S E N , J O N & E L I Z A B E T H REAL RE D L L C KOUNTZ , D A Y L E H KOUNTZ , D A Y L E H BUFFALO RUN BOZEMAN PROPERTY TOWERS , CHRISTO P H E R R FOWLER L A N E LLC COOK REVOCA B L E TRUST COOK, JE F F E R Y W & SARA H TOWERS , CHRISTO P H E R R PRESERVE EXISTING CMP CULVERT TO EAST TO MAINTAIN WATER ACCESS TO REAL RED LLC PROPERTY PRESERVE EXISTING CMP CULVERTS UNDER STUCKY ROAD ON EACH SIDE OF FOWLER LANE NEW CULVERT TO CONVEY LOCALIZED STORM RUNOFF FROM EAST SIDE DITCH. INSTALL 15" CMP AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW NEW 36" EQUIVALENT ARCH CMP CULVERT CROSSING. INSTALL CMP AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW TO MINIMIZE ENERGY/ WATER LOSS AND MINIMIZE DEBRIS BUILDUP. ALL IRRIGATION WATER CONVEYED WEST TO COMBINED DITCH NEW 30" EQUIVALENT ARCH PIPE CMP CULVERT TO BE ANGLED AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW TO MINIMIZE ENERGY/ WATER LOSS AND MINIMIZE DEBRIS BUILDUP. CULVERT INSTALLED TO PROVIDE DIVERSION FOR MSU WATER RIGHTS NO MODIFICATIONS TO EXISTING DITCHES SOUTH OF BLACKWOOD ROAD NEW CULVERT OF SPECIFIED SIZE (FLOW DIRECTION FROM EAST TO WEST) NO MODIFICATIONS TO EXISTING CULVERTS BENEATH BLACKWOOD ROAD AT INTERSECTION BOZEMAN H A U S T W O L L C KDG HOL D I N G S L L C >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>MAINTAIN EXISTING DIVERSION FOR BRADLEY PROPERTY March 18, 2022 Montana State University Office of Legal Counsel, MSU 211 Montana Hall PO Box 172420 Bozeman, MT 59717-2420 RE: Agreement for Relocation of the Middle Creek Ditch along Fowler Lane Dear Water Right Owner: In April of 2021, the Homestead at Buffalo Run project was approved by the City of Bozeman for annexation into the City with a R4 zoning classification. Currently, the project is going through the final stages of Site Plan approval from the City of Bozeman. As part of the Homestead at Buffalo Run project on Fowler Lane, the City of Bozeman is requiring that Fowler Lane be widened to an approved City section for a minor arterial classification (within the property limits of the project). As a result of this requirement, the irrigation ditch that currently runs along the east side of Fowler Lane is proposed to be relocated to the west side of Fowler Lane between Stucky Road and south of Blackwood Road. During the course of designing and engineering the project, our consultant team has been in consistent communication with the ditch companies and most of the private water owners on those same ditches. Calculations and design options have been provided and comments received from multiple parties. Modifications and revisions were made to the originally proposed design as a result of the comments and concerns that were expressed. Attached is an agreement with exhibits that reflect the final proposed design. We are requesting your signature on the attached agreement reflecting that you are in agreement with the proposed design for relocation of the water to be conveyed to the west side of Fowler. Based on calculations and engineering, the amount of water received by the water owners, or the point of diversion will not change and will be the same amount of water as historically received. If you have any questions, I and/or our legal counsel will be happy to answer them for you. Below is the contact information for those parties: • Derek Williams – derek@bridgerdevelop.com, 303-887-4045 • Susan Swimley - swimley@swimleylaw.com, 406-586-5544 • Abigail Brown - abby@mtwaterlaw.com, 406-457-5494 We are requesting the fully signed and executed agreement from you by Friday April 1, 2022. Thank you so much for your time and consideration. Sincerely, Buffalo Run Bozeman, LLC Derek Williams Manager/Member Cc: Susan Swimley Abigail Brown Page 1 of 5 DITCH RELOCATION AGREEMENT This Ditch Relocation Agreement (“Agreement”) is entered into this ______ day of ____________, 2022, by and between the Montana State University, with and address of Office of Legal Counsel, MSU, 211 Montana Hall, P.O. Box 172420, Bozeman, MT 59717-2420, (hereinafter referred to as “Water Right Owner”) and Buffalo Run Bozeman, LLC, a Colorado limited liability company of 5400 Fowler Lane, Bozeman, MT 59718 (hereinafter referred to as “BRB”) and collectively referred to as “the Parties”. WHEREAS, the Middle Creek Ditch Company and the West Gallatin Canal Company (hereinafter “Ditch Companies”) are the owners of an irrigation ditch system located in the southwest area of Bozeman and more particularly between Blackwood Road and Stucky Road (hereinafter referred to as the “Ditch”); WHEREAS, the Ditch Companies have established a ditch easement for the Ditch for the purpose of conveying irrigation water to their members’ real property; WHEREAS, the Water Right Owner owns private water right number 41H 107211-00 and private water right number 41H 139068-00, which rights are conveyed through the Ditch; WHEREAS, the Ditch runs parallel to Fowler Lane on both the east and west side of Fowler Lane; WHEREAS, BRB desires to relocate the east-side portions of the Ditch and improve the west-side portions of the Ditch to facilitate the improvements to Fowler Lane in accordance with approved plans required by the City of Bozeman and prepared by Morrison Maierle; and Page 2 of 5 WHEREAS, the Parties are desirous of formalizing an agreement between them which will define the terms and conditions under which BRB might relocate and improve the Ditch; NOW, THEREFORE, the Parties mutually covenant and agree as follows: 1. All recitals are incorporated herein as if fully set forth. 2. The Water Right Owner, subject to the terms and conditions set forth herein, shall permit BRB to relocate and improve the Ditch in accordance with approved plans prepared by Morrison Maierle and as set forth on Exhibit A attached hereto, which exhibit shall become an integral part of this Agreement. 3. Upon execution of this Agreement, the Water Right Owner shall review any and all plans, specifications, and drawings prepared by BRB or any engineer, agent, contractor, or other person on behalf of BRB which specify the nature of such construction methods and materials for the relocation and improvement of the Ditch including, but not limited to, description of materials, re-grading, cleaning, clearing of vegetation, realignment, or culverts which BRB intends to construct and which will encroach upon or in any way interfere with the Ditch. BRB shall provide the aforementioned plans, specifications, and drawings to the Water Right Owner as soon after execution of this Agreement as practicable. BRB acknowledges Water Right Owner may hire, at BRB’s expense, a qualified, third party professional engineer to review any plans, specifications, or drawings to determine if the same, once constructed, will provide for the adequate transport of water through the Ditch without jeopardizing the integrity of the Ditch. In the event the Water Right Owner shall determine the proposed relocation or improvement of the Ditch, once constructed, will not provide for the adequate transport of water through the new Ditch and/ or will jeopardize the integrity of the water conveyance, the Water Right Owner shall give notice of the same, together when any other findings, to BRB within fourteen (14) days of receipt of the aforementioned plans, specifications, and drawings. BRB shall have the right to cure the issues raised by the Water Right Owner. 5. During relocation and improvement of the Ditch, BRB shall be responsible for stabilizing the ditch bank around any culvert or pipeline openings so no sloughing occurs. 6. BRB agrees to reimburse Water Right Owner for any and all expenses it may incur in the preparation and recording of this Agreement including, but not limited to Water Right Owner staff time, reasonable attorney fees incurred by Water Right Owner to review this Agreement or any and all plans, drawings, or specifications for construction work or changes which BRB Page 3 of 5 undertakes pursuant to this Agreement. All fees and expenses to be paid under this Agreement shall be invoiced to BRB by the Water Right Owner no later than forty-five (45) days after the expense is incurred. BRB shall pay the Water Right Owner’s invoice(s) within forty-five (45) days of presentation to BRB by Water Right Owner. 7. BRB agrees the Water Right Owner may enter upon the Ditch and ditch easement during construction of the new Ditch for purposes of inspection, repair, operation and maintenance of the Ditch. However, at no time shall such entry interfere with the construction of the new Ditch or the on-going operations on the Property. 8. Under no circumstances shall BRB interrupt or in any way interfere with the flow of water through the Ditch at any time without prior written consent of the Water Right Owner. Permission to interrupt the flow of water will be granted based on the sole discretion of the Water Right Owner, but will not be unreasonably withheld and be consistent with achieving the purpose of this Agreement. 9. Upon BRB’s completion of the relocation and improvement of the Ditch, the Water Right Owner shall have the opportunity to inspect and confirm the relocated and improved Ditch operates and performs as expected. Once the Water Right Owner confirms the relocated and improved Ditch operates as expected, the Parties agree BRB shall have no further obligation to inspect, maintain, or repair the new Ditch. The Water Right Owner’s confirmation shall not be unreasonably withheld. 10. BRB hereby agrees to indemnify and hold the Water Right Owner harmless from any and all claims, causes of action, costs, and reasonable attorney fees which the Water Right Owner may sustain by reason of or in connection with any claim filed against it for any event which may occur during BRB’s relocation and improvement of the Ditch or as a result of any action by BRB, its successors, agents, assigns or property owner(s). 11. All covenants and agreements herein contained shall extend to and be binding upon the heirs, personal representatives, assigns, or successors of the respective parties hereto and shall run with the title of the property in perpetuity unless rescinded in writing by the Water Right Owner. 12. This Agreement constitutes the entire agreement and understanding between the parties hereto and supersedes all prior and contemporaneous agreements and understandings of the parties in connection herewith which conflict with the expressed terms, covenants, and Page 4 of 5 conditions of this Agreement. Covenant, representation, or condition not expressed in this Agreement shall not be effective to interpret, change, or restrict the express provisions of this Agreement unless specified in writing and signed by both parties hereto. 13. If it becomes necessary for either party hereto to bring suit to enforce their rights under this Agreement and if that party shall prevail in such action, the other party agrees to pay all of the costs of the action as allowed by the Court together with reasonable attorney fees. 14. Nothing in this Agreement is intended to convey any ownership interest in the water rights owned by Water Right Owner nor any permission to use water conveyed in the Ditch pursuant to a water right in any manner not consistent with Montana law. BRB is expressly prohibited from seeking to change any elements of Water Right Owner’s water rights without the express written consent of Water Right Owner. 15. This Agreement may be signed in counterparts, paper or electronic, each of which shall constitute an original, and all of which will be collectively deemed to constitute one document. 16. The Parties represent and warrant that they have read this Agreement, and each and every part thereof; that they understand the terms and conditions; and have consulted with counsel with respect thereto; and that they accept, agree to and intend to be bound by the terms and conditions of this Agreement. IN WITNESS WHEREOF, the parties hereto have signed and sealed this Agreement the day and year above first written. MONTANA STATE UNIVERSITY _________________________________ By:______________________________ Its:______________________________ STATE OF MONTANA ) : ss. COUNTY OF GALLATIN ) This instrument was acknowledged before me on _____________________2022, by ___________________, as _______________ of Montana State University. ___________________________________ Notary State of Montana (seal) Printed Name: ______________________ Page 5 of 5 BUFFALO RUN BOZEMAN, LLC: __________________________________ BY:_______________________________ Its: Manager STATE OF MONTANA ) : ss. COUNTY OF GALLATIN ) This instrument was acknowledged before me on _____________________2022, by __________________, as Manager of Buffalo Run Bozeman, LLC. ___________________________________ Notary State of Montana (seal) Printed Name: _______________________ LEGEND PROPOSED WEST SIDE DITCH IMPROVEMENTS FOR COMBINED FLOW ALONG COUNTY ROAD SECTIONS NEW CULVERT OF SPECIFIED SIZE (FLOW DIRECTION FROM WEST TO EAST) PROPOSED WEST SIDE DITCH OPTION THROUGHOUT PROPERTY FRONTAGE FIGURE NUMBER © PROJECT NO.DRAWN BY: DSGN. BY: APPR. BY: DATE: COPYRIGHT MORRISON-MAIERLE, INC.,2022 N:\6475\003 - Offsite Imps - Fowler and S 27th\ACAD\Exhibits\6475.003_DITCH REALIGNMENT VICINITY MAP.dwg Plotted by lee hageman on Mar/11/2022 engineers surveyors planners scientists MorrisonMaierle 2880 Technology Blvd West Bozeman, MT 59718 406.587.0721 www.m-m.net 6475.003 EX-A BUFFALO RUN - OFFSITE IMPROVEMENTS BOZEMAN MONTANA FOWLER LANE IRRIGATION DITCH REALIGNMENT OPTION #2 LRH LRH LRH 03/11/2022 N.T.S. BLACKWOOD ROAD STUCKY ROAD FOWLER LANEHERIZA, T H O M A S J & M A Y L HAGGER T Y F A M I L Y 2B HOLD I N G S GAVIN, W I L L I A M M B & R E N E E R BRADLEY P L A C E KOUNTZ , D A Y L E H CHRISTE N S E N , J O N & E L I Z A B E T H REAL RE D L L C KOUNTZ , D A Y L E H KOUNTZ , D A Y L E H BUFFALO RUN BOZEMAN PROPERTY TOWERS , CHRISTO P H E R R FOWLER L A N E LLC COOK REVOCA B L E TRUST COOK, JE F F E R Y W & SARA H TOWERS , CHRISTO P H E R R PRESERVE EXISTING CMP CULVERT TO EAST TO MAINTAIN WATER ACCESS TO REAL RED LLC PROPERTY PRESERVE EXISTING CMP CULVERTS UNDER STUCKY ROAD ON EACH SIDE OF FOWLER LANE NEW CULVERT TO CONVEY LOCALIZED STORM RUNOFF FROM EAST SIDE DITCH. INSTALL 15" CMP AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW NEW 36" EQUIVALENT ARCH CMP CULVERT CROSSING. INSTALL CMP AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW TO MINIMIZE ENERGY/ WATER LOSS AND MINIMIZE DEBRIS BUILDUP. ALL IRRIGATION WATER CONVEYED WEST TO COMBINED DITCH NEW 30" EQUIVALENT ARCH PIPE CMP CULVERT TO BE ANGLED AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW TO MINIMIZE ENERGY/ WATER LOSS AND MINIMIZE DEBRIS BUILDUP. CULVERT INSTALLED TO PROVIDE DIVERSION FOR MSU WATER RIGHTS NO MODIFICATIONS TO EXISTING DITCHES SOUTH OF BLACKWOOD ROAD NEW CULVERT OF SPECIFIED SIZE (FLOW DIRECTION FROM EAST TO WEST) NO MODIFICATIONS TO EXISTING CULVERTS BENEATH BLACKWOOD ROAD AT INTERSECTION BOZEMAN H A U S T W O L L C KDG HOL D I N G S L L C >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>MAINTAIN EXISTING DIVERSION FOR BRADLEY PROPERTY March 18, 2022 Bradley Family Revocable Trust 5912 Our Way Citrus Heights, CA 95610-6709 RE: Agreement for Relocation of the Middle Creek Ditch along Fowler Lane Dear Water Right Owner: In April of 2021, the Homestead at Buffalo Run project was approved by the City of Bozeman for annexation into the City with a R4 zoning classification. Currently, the project is going through the final stages of Site Plan approval from the City of Bozeman. As part of the Homestead at Buffalo Run project on Fowler Lane, the City of Bozeman is requiring that Fowler Lane be widened to an approved City section for a minor arterial classification (within the property limits of the project). As a result of this requirement, the irrigation ditch that currently runs along the east side of Fowler Lane is proposed to be relocated to the west side of Fowler Lane between Stucky Road and south of Blackwood Road. During the course of designing and engineering the project, our consultant team has been in consistent communication with the ditch companies and most of the private water owners on those same ditches. Calculations and design options have been provided and comments received from multiple parties. Modifications and revisions were made to the originally proposed design as a result of the comments and concerns that were expressed. Attached is an agreement with exhibits that reflect the final proposed design. We are requesting your signature on the attached agreement reflecting that you are in agreement with the proposed design for relocation of the water to be conveyed to the west side of Fowler. Based on calculations and engineering, the amount of water received by the water owners, or the point of diversion will not change and will be the same amount of water as historically received. If you have any questions, I and/or our legal counsel will be happy to answer them for you. Below is the contact information for those parties: • Derek Williams – derek@bridgerdevelop.com, 303-887-4045 • Susan Swimley - swimley@swimleylaw.com, 406-586-5544 • Abigail Brown - abby@mtwaterlaw.com, 406-457-5494 We are requesting the fully signed and executed agreement from you by Friday April 1, 2022. Thank you so much for your time and consideration. Sincerely, Buffalo Run Bozeman, LLC Derek Williams Manager/Member Cc: Susan Swimley Abigail Brown Page 1 of 7 DITCH RELOCATION AGREEMENT This Ditch Relocation Agreement (“Agreement”) is entered into this ______ day of ____________, 2022, by and between the Bradley Family Revocable Trust, with an address of 5912 Our Way, Citrus Heights, CA 95610-6709, Gordon & Jacklyn Bradley Family Trust, with an address of 3852 46th Ave. NE, Seattle, WA 98105; and Glenn David Cowles Trust, with an address of 5912 Our Way, Citrus Heights, CA 95601-6709 (hereinafter collectively referred to as “Water Right Owner”) and Buffalo Run Bozeman, LLC, a Colorado limited liability company of 5400 Fowler Lane, Bozeman, MT 59718 (hereinafter referred to as “BRB”) and collectively referred to as “the Parties”. WHEREAS, the Middle Creek Ditch Company and the West Gallatin Canal Company (hereinafter “Ditch Companies”) are the owners of an irrigation ditch system located in the southwest area of Bozeman and more particularly between Blackwood Road and Stucky Road (hereinafter referred to as the “Ditch”); WHEREAS, the Ditch Companies have established a ditch easement for the Ditch for the purpose of conveying irrigation water to their members’ real property; WHEREAS, the Water Right Owner owns private water right number 41H 35506-00, which is conveyed through the Ditch; WHEREAS, the Ditch runs parallel to Fowler Lane on both the east and west side of Fowler Lane; WHEREAS, BRB desires to relocate the east-side portions of the Ditch and improve the west-side portions of the Ditch to facilitate the improvements to Fowler Lane in accordance with approved plans required by the City of Bozeman and prepared by Morrison Maierle; and WHEREAS, the Parties are desirous of formalizing an agreement between them which will define the terms and conditions under which BRB might relocate and improve the Ditch; NOW, THEREFORE, the Parties mutually covenant and agree as follows: Page 2 of 7 1. All recitals are incorporated herein as if fully set forth. 2. The Water Right Owner, subject to the terms and conditions set forth herein, shall permit BRB to relocate and improve the Ditch in accordance with approved plans prepared by Morrison Maierle and as set forth on Exhibit A attached hereto, which exhibit shall become an integral part of this Agreement. 3. Upon execution of this Agreement, the Water Right Owner shall review any and all plans, specifications, and drawings prepared by BRB or any engineer, agent, contractor, or other person on behalf of BRB which specify the nature of such construction methods and materials for the relocation and improvement of the Ditch including, but not limited to, description of materials, re-grading, cleaning, clearing of vegetation, realignment, or culverts which BRB intends to construct and which will encroach upon or in any way interfere with the Ditch. BRB shall provide the aforementioned plans, specifications, and drawings to the Water Right Owner as soon after execution of this Agreement as practicable. BRB acknowledges Water Right Owner may hire, at BRB’s expense, a qualified, third party professional engineer to review any plans, specifications, or drawings to determine if the same, once constructed, will provide for the adequate transport of water through the Ditch without jeopardizing the integrity of the Ditch. In the event the Water Right Owner shall determine the proposed relocation or improvement of the Ditch, once constructed, will not provide for the adequate transport of water through the new Ditch and/ or will jeopardize the integrity of the water conveyance, the Water Right Owner shall give notice of the same, together when any other findings, to BRB within fourteen (14) days of receipt of the aforementioned plans, specifications, and drawings. BRB shall have the right to cure the issues raised by the Water Right Owner. 5. During relocation and improvement of the Ditch, BRB shall be responsible for stabilizing the ditch bank around any culvert or pipeline openings so no sloughing occurs. 6. BRB agrees to reimburse Water Right Owner for any and all expenses it may incur in the preparation and recording of this Agreement including, but not limited to Water Right Owner staff time, reasonable attorney fees incurred by Water Right Owner to review this Agreement or any and all plans, drawings, or specifications for construction work or changes which BRB undertakes pursuant to this Agreement. All fees and expenses to be paid under this Agreement shall be invoiced to BRB by the Water Right Owner no later than forty-five (45) days after the expense is incurred. BRB shall pay the Water Right Owner’s invoice(s) within forty-five (45) days of presentation to BRB by Water Right Owner. Page 3 of 7 7. BRB agrees the Water Right Owner may enter upon the Ditch and ditch easement during construction of the new Ditch for purposes of inspection, repair, operation and maintenance of the Ditch. However, at no time shall such entry interfere with the construction of the new Ditch or the on-going operations on the Property. 8. Under no circumstances shall BRB interrupt or in any way interfere with the flow of water through the Ditch at any time without prior written consent of the Water Right Owner. Permission to interrupt the flow of water will be granted based on the sole discretion of the Water Right Owner, but will not be unreasonably withheld and be consistent with achieving the purpose of this Agreement. 9. Upon BRB’s completion of the relocation and improvement of the Ditch, the Water Right Owner shall have the opportunity to inspect and confirm the relocated and improved Ditch operates and performs as expected. Once the Water Right Owner confirms the relocated and improved Ditch operates as expected, the Parties agree BRB shall have no further obligation to inspect, maintain, or repair the new Ditch. The Water Right Owner’s confirmation shall not be unreasonably withheld. 10. BRB hereby agrees to indemnify and hold the Water Right Owner harmless from any and all claims, causes of action, costs, and reasonable attorney fees which the Water Right Owner may sustain by reason of or in connection with any claim filed against it for any event which may occur during BRB’s relocation and improvement of the Ditch or as a result of any action by BRB, its successors, agents, assigns or property owner(s). 11. All covenants and agreements herein contained shall extend to and be binding upon the heirs, personal representatives, assigns, or successors of the respective parties hereto and shall run with the title of the property in perpetuity unless rescinded in writing by the Water Right Owner. 12. This Agreement constitutes the entire agreement and understanding between the parties hereto and supersedes all prior and contemporaneous agreements and understandings of the parties in connection herewith which conflict with the expressed terms, covenants, and conditions of this Agreement. Covenant, representation, or condition not expressed in this Agreement shall not be effective to interpret, change, or restrict the express provisions of this Agreement unless specified in writing and signed by both parties hereto. 13. If it becomes necessary for either party hereto to bring suit to enforce their rights under this Agreement and if that party shall prevail in such action, the other party agrees to pay Page 4 of 7 all of the costs of the action as allowed by the Court together with reasonable attorney fees. 14. Nothing in this Agreement is intended to convey any ownership interest in the water rights owned by Water Right Owner nor any permission to use water conveyed in the Ditch pursuant to a water right in any manner not consistent with Montana law. BRB is expressly prohibited from seeking to change any elements of Water Right Owner’s water rights without the express written consent of Water Right Owner. 15. This Agreement may be signed in counterparts, paper or electronic, each of which shall constitute an original, and all of which will be collectively deemed to constitute one document. 16. The Parties represent and warrant that they have read this Agreement, and each and every part thereof; that they understand the terms and conditions; and have consulted with counsel with respect thereto; and that they accept, agree to and intend to be bound by the terms and conditions of this Agreement. IN WITNESS WHEREOF, the parties hereto have signed and sealed this Agreement the day and year above first written. [Signatures on Pages Immediately Following] Page 5 of 7 BRADLEY FAMILY REVOCABLE TRUST ________________________________ By:______________________________ Its:______________________________ STATE OF MONTANA ) : ss. COUNTY OF GALLATIN ) This instrument was acknowledged before me on _____________________2022, by ___________________, as _______________ of Bradley Family Revocable Trust. ___________________________________ Notary State of Montana (seal) Printed Name: _______________________ GORDON & JACKLYN BRADLEY FAMILY TRUST ________________________________ By:______________________________ Its:______________________________ STATE OF MONTANA ) : ss. COUNTY OF GALLATIN ) This instrument was acknowledged before me on _____________________2022, by ___________________, as _______________ of Bradley, Gordon & Jacklyn Family Trust. ___________________________________ Notary State of Montana (seal) Printed Name: _______________________ Page 6 of 7 GLENN DAVID COWLES TRUST ________________________________ By:______________________________ Its:______________________________ STATE OF MONTANA ) : ss. COUNTY OF GALLATIN ) This instrument was acknowledged before me on _____________________2022, by ___________________, as _______________ of Cowles, Glenn David Trust. ___________________________________ Notary State of Montana (seal) Printed Name: _______________________ Page 7 of 7 BUFFALO RUN BOZEMAN, LLC: __________________________________ BY:_______________________________ Its: Manager STATE OF MONTANA ) : ss. COUNTY OF GALLATIN ) This instrument was acknowledged before me on _____________________2022, by __________________, as Manager of Buffalo Run Bozeman, LLC. ___________________________________ Notary State of Montana (seal) Printed Name: _______________________ LEGEND PROPOSED WEST SIDE DITCH IMPROVEMENTS FOR COMBINED FLOW ALONG COUNTY ROAD SECTIONS NEW CULVERT OF SPECIFIED SIZE (FLOW DIRECTION FROM WEST TO EAST) PROPOSED WEST SIDE DITCH OPTION THROUGHOUT PROPERTY FRONTAGE FIGURE NUMBER © PROJECT NO.DRAWN BY: DSGN. BY: APPR. BY: DATE: COPYRIGHT MORRISON-MAIERLE, INC.,2022 N:\6475\003 - Offsite Imps - Fowler and S 27th\ACAD\Exhibits\6475.003_DITCH REALIGNMENT VICINITY MAP.dwg Plotted by lee hageman on Mar/11/2022 engineers surveyors planners scientists MorrisonMaierle 2880 Technology Blvd West Bozeman, MT 59718 406.587.0721 www.m-m.net 6475.003 EX-A BUFFALO RUN - OFFSITE IMPROVEMENTS BOZEMAN MONTANA FOWLER LANE IRRIGATION DITCH REALIGNMENT OPTION #2 LRH LRH LRH 03/11/2022 N.T.S. BLACKWOOD ROAD STUCKY ROAD FOWLER LANEHERIZA, T H O M A S J & M A Y L HAGGER T Y F A M I L Y 2B HOLD I N G S GAVIN, W I L L I A M M B & R E N E E R BRADLEY P L A C E KOUNTZ , D A Y L E H CHRISTE N S E N , J O N & E L I Z A B E T H REAL RE D L L C KOUNTZ , D A Y L E H KOUNTZ , D A Y L E H BUFFALO RUN BOZEMAN PROPERTY TOWERS , CHRISTO P H E R R FOWLER L A N E LLC COOK REVOCA B L E TRUST COOK, JE F F E R Y W & SARA H TOWERS , CHRISTO P H E R R PRESERVE EXISTING CMP CULVERT TO EAST TO MAINTAIN WATER ACCESS TO REAL RED LLC PROPERTY PRESERVE EXISTING CMP CULVERTS UNDER STUCKY ROAD ON EACH SIDE OF FOWLER LANE NEW CULVERT TO CONVEY LOCALIZED STORM RUNOFF FROM EAST SIDE DITCH. INSTALL 15" CMP AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW NEW 36" EQUIVALENT ARCH CMP CULVERT CROSSING. INSTALL CMP AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW TO MINIMIZE ENERGY/ WATER LOSS AND MINIMIZE DEBRIS BUILDUP. ALL IRRIGATION WATER CONVEYED WEST TO COMBINED DITCH NEW 30" EQUIVALENT ARCH PIPE CMP CULVERT TO BE ANGLED AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW TO MINIMIZE ENERGY/ WATER LOSS AND MINIMIZE DEBRIS BUILDUP. CULVERT INSTALLED TO PROVIDE DIVERSION FOR MSU WATER RIGHTS NO MODIFICATIONS TO EXISTING DITCHES SOUTH OF BLACKWOOD ROAD NEW CULVERT OF SPECIFIED SIZE (FLOW DIRECTION FROM EAST TO WEST) NO MODIFICATIONS TO EXISTING CULVERTS BENEATH BLACKWOOD ROAD AT INTERSECTION BOZEMAN H A U S T W O L L C KDG HOL D I N G S L L C >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>MAINTAIN EXISTING DIVERSION FOR BRADLEY PROPERTY March 18, 2022 Haggerty Family, LLC 5100 Patterson Road Bozeman, MT 59718 RE: Agreement for Relocation of the Middle Creek Ditch along Fowler Lane Dear Mr. and Mrs. Haggerty: In April of 2021, the Homestead at Buffalo Run project was approved by the City of Bozeman for annexation into the City with a R4 zoning classification. Currently, the project is going through the final stages of Site Plan approval from the City of Bozeman. As part of the Homestead at Buffalo Run project on Fowler Lane, the City of Bozeman is requiring that Fowler Lane be widened to an approved City section for a minor arterial classification (within the property limits of the project). As a result of this requirement, the irrigation ditch that currently runs along the east side of Fowler Lane is proposed to be relocated to the west side of Fowler Lane between Stucky Road and south of Blackwood Road. During the course of designing and engineering the project, our consultant team has been in consistent communication with the ditch companies and most of the private water owners on those same ditches. Calculations and design options have been provided and comments received from multiple parties. Modifications and revisions were made to the originally proposed design as a result of the comments and concerns that were expressed. Attached is an agreement with exhibits that reflect the final proposed design. We are requesting your signature on the attached agreement reflecting that you are in agreement with the proposed design for relocation of the water to be conveyed to the west side of Fowler. Based on calculations and engineering, the amount of water received by the water owners, or the point of diversion will not change and will be the same amount of water as historically received. If you have any questions, I and/or our legal counsel will be happy to answer them for you. Below is the contact information for those parties: •Derek Williams – derek@bridgerdevelop.com, 303-887-4045 •Susan Swimley - swimley@swimleylaw.com, 406-586-5544 •Abigail Brown - abby@mtwaterlaw.com, 406-457-5494 We are requesting the fully signed and executed agreement from you by Friday April 1, 2022. Thank you so much for your time and consideration. Sincerely, Buffalo Run Bozeman, LLC Derek Williams Manager/Member Cc: Susan Swimley Abigail Brown Page 1 of 5 DITCH RELOCATION AGREEMENT This Ditch Relocation Agreement (“Agreement”) is entered into this ______ day of ____________, 2022, by and between the Haggerty Family, LLC, a Montana limited liability corporation with address of 5100 Patterson Road, Bozeman, MT 59718, (hereinafter referred to as “Water Right Owner”) and Buffalo Run Bozeman, LLC, a Colorado limited liability company of 5400 Fowler Lane, Bozeman, MT 59718 (hereinafter referred to as “BRB”) and collectively referred to as “the Parties”. WHEREAS, the Middle Creek Ditch Company and the West Gallatin Canal Company (hereinafter “Ditch Companies”) are the owners of an irrigation ditch system located in the southwest area of Bozeman and more particularly between Blackwood Road and Stucky Road (hereinafter referred to as the “Ditch”); WHEREAS, the Ditch Companies have established a ditch easement for the Ditch for the purpose of conveying irrigation water to their members’ real property; WHEREAS, the Water Right Owner owns private water right number 41H 139072-00, which is conveyed through the Ditch; WHEREAS, the Ditch runs parallel to Fowler Lane on both the east and west side of Fowler Lane; WHEREAS, BRB desires to relocate the east-side portions of the Ditch and improve the west-side portions of the Ditch to facilitate the improvements to Fowler Lane in accordance with approved plans required by the City of Bozeman and prepared by Morrison Maierle; and Page 2 of 5 WHEREAS, the Parties are desirous of formalizing an agreement between them which will define the terms and conditions under which BRB might relocate and improve the Ditch; NOW, THEREFORE, the Parties mutually covenant and agree as follows: 1. All recitals are incorporated herein as if fully set forth. 2. The Water Right Owner, subject to the terms and conditions set forth herein, shall permit BRB to relocate and improve the Ditch in accordance with approved plans prepared by Morrison Maierle and as set forth on Exhibit A attached hereto, which exhibit shall become an integral part of this Agreement. 3. Upon execution of this Agreement, the Water Right Owner shall review any and all plans, specifications, and drawings prepared by BRB or any engineer, agent, contractor, or other person on behalf of BRB which specify the nature of such construction methods and materials for the relocation and improvement of the Ditch including, but not limited to, description of materials, re-grading, cleaning, clearing of vegetation, realignment, or culverts which BRB intends to construct and which will encroach upon or in any way interfere with the Ditch. BRB shall provide the aforementioned plans, specifications, and drawings to the Water Right Owner as soon after execution of this Agreement as practicable. BRB acknowledges Water Right Owner may hire, at BRB’s expense, a qualified, third party professional engineer to review any plans, specifications, or drawings to determine if the same, once constructed, will provide for the adequate transport of water through the Ditch without jeopardizing the integrity of the Ditch. In the event the Water Right Owner shall determine the proposed relocation or improvement of the Ditch, once constructed, will not provide for the adequate transport of water through the new Ditch and/ or will jeopardize the integrity of the water conveyance, the Water Right Owner shall give notice of the same, together when any other findings, to BRB within fourteen (14) days of receipt of the aforementioned plans, specifications, and drawings. BRB shall have the right to cure the issues raised by the Water Right Owner. 5. During relocation and improvement of the Ditch, BRB shall be responsible for stabilizing the ditch bank around any culvert or pipeline openings so no sloughing occurs. 6. BRB agrees to reimburse Water Right Owner for any and all expenses it may incur in the preparation and recording of this Agreement including, but not limited to Water Right Owner staff time, reasonable attorney fees incurred by Water Right Owner to review this Agreement or any and all plans, drawings, or specifications for construction work or changes which BRB Page 3 of 5 undertakes pursuant to this Agreement. All fees and expenses to be paid under this Agreement shall be invoiced to BRB by the Water Right Owner no later than forty-five (45) days after the expense is incurred. BRB shall pay the Water Right Owner’s invoice(s) within forty-five (45) days of presentation to BRB by Water Right Owner. 7. BRB agrees the Water Right Owner may enter upon the Ditch and ditch easement during construction of the new Ditch for purposes of inspection, repair, operation and maintenance of the Ditch. However, at no time shall such entry interfere with the construction of the new Ditch or the on-going operations on the Property. 8. Under no circumstances shall BRB interrupt or in any way interfere with the flow of water through the Ditch at any time without prior written consent of the Water Right Owner. Permission to interrupt the flow of water will be granted based on the sole discretion of the Water Right Owner, but will not be unreasonably withheld and be consistent with achieving the purpose of this Agreement. 9. Upon BRB’s completion of the relocation and improvement of the Ditch, the Water Right Owner shall have the opportunity to inspect and confirm the relocated and improved Ditch operates and performs as expected. Once the Water Right Owner confirms the relocated and improved Ditch operates as expected, the Parties agree BRB shall have no further obligation to inspect, maintain, or repair the new Ditch. The Water Right Owner’s confirmation shall not be unreasonably withheld. 10. BRB hereby agrees to indemnify and hold the Water Right Owner harmless from any and all claims, causes of action, costs, and reasonable attorney fees which the Water Right Owner may sustain by reason of or in connection with any claim filed against it for any event which may occur during BRB’s relocation and improvement of the Ditch or as a result of any action by BRB, its successors, agents, assigns or property owner(s). 11. All covenants and agreements herein contained shall extend to and be binding upon the heirs, personal representatives, assigns, or successors of the respective parties hereto and shall run with the title of the property in perpetuity unless rescinded in writing by the Water Right Owner. 12. This Agreement constitutes the entire agreement and understanding between the parties hereto and supersedes all prior and contemporaneous agreements and understandings of the parties in connection herewith which conflict with the expressed terms, covenants, and Page 4 of 5 conditions of this Agreement. Covenant, representation, or condition not expressed in this Agreement shall not be effective to interpret, change, or restrict the express provisions of this Agreement unless specified in writing and signed by both parties hereto. 13. If it becomes necessary for either party hereto to bring suit to enforce their rights under this Agreement and if that party shall prevail in such action, the other party agrees to pay all of the costs of the action as allowed by the Court together with reasonable attorney fees. 14. Nothing in this Agreement is intended to convey any ownership interest in the water rights owned by Water Right Owner nor any permission to use water conveyed in the Ditch pursuant to a water right in any manner not consistent with Montana law. BRB is expressly prohibited from seeking to change any elements of Water Right Owner’s water rights without the express written consent of Water Right Owner. 15. This Agreement may be signed in counterparts, paper or electronic, each of which shall constitute an original, and all of which will be collectively deemed to constitute one document. 16. The Parties represent and warrant that they have read this Agreement, and each and every part thereof; that they understand the terms and conditions; and have consulted with counsel with respect thereto; and that they accept, agree to and intend to be bound by the terms and conditions of this Agreement. IN WITNESS WHEREOF, the parties hereto have signed and sealed this Agreement the day and year above first written. HAGGERTY FAMILY, LLC _________________________________ By:______________________________ Its:______________________________ STATE OF MONTANA ) : ss. COUNTY OF GALLATIN ) This instrument was acknowledged before me on _____________________2022, by ___________________, as _______________ of Haggerty Family, LLC. ___________________________________ Notary State of Montana (seal) Printed Name: _______________________ Page 5 of 5 BUFFALO RUN BOZEMAN, LLC: __________________________________ BY:_______________________________ Its: Manager STATE OF MONTANA ) : ss. COUNTY OF GALLATIN ) This instrument was acknowledged before me on _____________________2022, by __________________, as Manager of Buffalo Run Bozeman, LLC. ___________________________________ Notary State of Montana (seal) Printed Name: _______________________ LEGEND PROPOSED WEST SIDE DITCH IMPROVEMENTS FOR COMBINED FLOW ALONG COUNTY ROAD SECTIONS NEW CULVERT OF SPECIFIED SIZE (FLOW DIRECTION FROM WEST TO EAST) PROPOSED WEST SIDE DITCH OPTION THROUGHOUT PROPERTY FRONTAGE FIGURE NUMBER © PROJECT NO.DRAWN BY: DSGN. BY: APPR. BY: DATE: COPYRIGHT MORRISON-MAIERLE, INC.,2022 N:\6475\003 - Offsite Imps - Fowler and S 27th\ACAD\Exhibits\6475.003_DITCH REALIGNMENT VICINITY MAP.dwg Plotted by lee hageman on Mar/11/2022 engineers surveyors planners scientists MorrisonMaierle 2880 Technology Blvd West Bozeman, MT 59718 406.587.0721 www.m-m.net 6475.003 EX-A BUFFALO RUN - OFFSITE IMPROVEMENTS BOZEMAN MONTANA FOWLER LANE IRRIGATION DITCH REALIGNMENT OPTION #2 LRH LRH LRH 03/11/2022 N.T.S. BLACKWOOD ROAD STUCKY ROAD FOWLER LANEHERIZA, T H O M A S J & M A Y L HAGGER T Y F A M I L Y 2B HOLD I N G S GAVIN, W I L L I A M M B & R E N E E R BRADLEY P L A C E KOUNTZ , D A Y L E H CHRISTE N S E N , J O N & E L I Z A B E T H REAL RE D L L C KOUNTZ , D A Y L E H KOUNTZ , D A Y L E H BUFFALO RUN BOZEMAN PROPERTY TOWERS , CHRISTO P H E R R FOWLER L A N E LLC COOK REVOCA B L E TRUST COOK, JE F F E R Y W & SARA H TOWERS , CHRISTO P H E R R PRESERVE EXISTING CMP CULVERT TO EAST TO MAINTAIN WATER ACCESS TO REAL RED LLC PROPERTY PRESERVE EXISTING CMP CULVERTS UNDER STUCKY ROAD ON EACH SIDE OF FOWLER LANE NEW CULVERT TO CONVEY LOCALIZED STORM RUNOFF FROM EAST SIDE DITCH. INSTALL 15" CMP AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW NEW 36" EQUIVALENT ARCH CMP CULVERT CROSSING. INSTALL CMP AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW TO MINIMIZE ENERGY/ WATER LOSS AND MINIMIZE DEBRIS BUILDUP. ALL IRRIGATION WATER CONVEYED WEST TO COMBINED DITCH NEW 30" EQUIVALENT ARCH PIPE CMP CULVERT TO BE ANGLED AT 45° ANGLE TO ROAD IN DIRECTION OF FLOW TO MINIMIZE ENERGY/ WATER LOSS AND MINIMIZE DEBRIS BUILDUP. CULVERT INSTALLED TO PROVIDE DIVERSION FOR MSU WATER RIGHTS NO MODIFICATIONS TO EXISTING DITCHES SOUTH OF BLACKWOOD ROAD NEW CULVERT OF SPECIFIED SIZE (FLOW DIRECTION FROM EAST TO WEST) NO MODIFICATIONS TO EXISTING CULVERTS BENEATH BLACKWOOD ROAD AT INTERSECTION BOZEMAN H A U S T W O L L C KDG HOL D I N G S L L C >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>MAINTAIN EXISTING DIVERSION FOR BRADLEY PROPERTY Appendix A NRCS Soils Report United States Department of Agriculture A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Gallatin County Area, Montana Buffalo Run Natural Resources Conservation Service July 20, 2020 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/ portal/nrcs/main/soils/health/) and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State Soil Scientist (http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/? cid=nrcs142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require 2 alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 Contents Preface....................................................................................................................2 How Soil Surveys Are Made..................................................................................5 Soil Map..................................................................................................................8 Soil Map................................................................................................................9 Legend................................................................................................................10 Map Unit Legend................................................................................................11 Map Unit Descriptions.........................................................................................11 Gallatin County Area, Montana.......................................................................13 448A—Hyalite-Beaverton complex, moderately wet, 0 to 2 percent slopes....................................................................................................13 457A—Turner loam, moderately wet, 0 to 2 percent slopes.......................15 510B—Meadowcreek loam, 0 to 4 percent slopes......................................16 References............................................................................................................18 4 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil-vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil 5 scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil-landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil-landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field-observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and Custom Soil Resource Report 6 identified each as a specific map unit. Aerial photographs show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. Custom Soil Resource Report 7 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 8 9 Custom Soil Resource Report Soil Map 50544305054480505453050545805054630505468050547305054430505448050545305054580505463050546805054730493480 493530 493580 493630 493680 493730 493780 493830 493880 493930 493480 493530 493580 493630 493680 493730 493780 493830 493880 493930 45° 38' 46'' N 111° 5' 2'' W45° 38' 46'' N111° 4' 39'' W45° 38' 35'' N 111° 5' 2'' W45° 38' 35'' N 111° 4' 39'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 12N WGS84 0 100 200 400 600 Feet 0 30 60 120 180 Meters Map Scale: 1:2,220 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Gallatin County Area, Montana Survey Area Data: Version 24, Jun 4, 2020 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Aug 3, 2009—Sep 1, 2016 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 10 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 448A Hyalite-Beaverton complex, moderately wet, 0 to 2 percent slopes 5.8 27.8% 457A Turner loam, moderately wet, 0 to 2 percent slopes 13.6 65.2% 510B Meadowcreek loam, 0 to 4 percent slopes 1.4 7.0% Totals for Area of Interest 20.8 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or Custom Soil Resource Report 11 landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha-Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. Custom Soil Resource Report 12 Gallatin County Area, Montana 448A—Hyalite-Beaverton complex, moderately wet, 0 to 2 percent slopes Map Unit Setting National map unit symbol: 56sq Elevation: 4,450 to 5,300 feet Mean annual precipitation: 15 to 19 inches Mean annual air temperature: 39 to 45 degrees F Frost-free period: 90 to 110 days Farmland classification: Farmland of local importance Map Unit Composition Hyalite and similar soils: 70 percent Beaverton and similar soils: 20 percent Minor components: 10 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Hyalite Setting Landform: Alluvial fans, stream terraces Down-slope shape: Linear Across-slope shape: Linear Parent material: Loamy alluvium Typical profile A - 0 to 5 inches: loam Bt1 - 5 to 9 inches: clay loam Bt2 - 9 to 17 inches: silty clay loam 2Bt3 - 17 to 26 inches: very cobbly sandy clay loam 3C - 26 to 60 inches: very cobbly loamy sand Properties and qualities Slope: 0 to 2 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Capacity of the most limiting layer to transmit water (Ksat): Moderately high (0.20 to 0.57 in/hr) Depth to water table: About 48 to 96 inches Frequency of flooding: None Frequency of ponding: None Calcium carbonate, maximum in profile: 5 percent Available water storage in profile: Low (about 4.4 inches) Interpretive groups Land capability classification (irrigated): 3e Land capability classification (nonirrigated): 4e Hydrologic Soil Group: C Ecological site: Upland Grassland (R043BP818MT) Hydric soil rating: No Custom Soil Resource Report 13 Description of Beaverton Setting Landform: Alluvial fans, stream terraces Down-slope shape: Linear Across-slope shape: Linear Parent material: Alluvium Typical profile A - 0 to 5 inches: cobbly loam Bt - 5 to 21 inches: very gravelly clay loam Bk - 21 to 25 inches: very cobbly coarse sandy loam 2Bk - 25 to 60 inches: extremely cobbly loamy coarse sand Properties and qualities Slope: 0 to 2 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: About 48 to 96 inches Frequency of flooding: None Frequency of ponding: None Calcium carbonate, maximum in profile: 15 percent Salinity, maximum in profile: Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm) Available water storage in profile: Low (about 3.7 inches) Interpretive groups Land capability classification (irrigated): 4s Land capability classification (nonirrigated): 6s Hydrologic Soil Group: B Ecological site: Upland Grassland (R043BP818MT) Hydric soil rating: No Minor Components Meadowcreek Percent of map unit: 5 percent Landform: Stream terraces Down-slope shape: Linear Across-slope shape: Linear Ecological site: Subirrigated (Sb) 15-19" p.z. (R044XS359MT) Hydric soil rating: No Beaverton Percent of map unit: 5 percent Landform: Stream terraces, alluvial fans Down-slope shape: Linear Across-slope shape: Linear Ecological site: Shallow to Gravel (SwGr) 15-19" p.z. (R044XS354MT) Hydric soil rating: No Custom Soil Resource Report 14 457A—Turner loam, moderately wet, 0 to 2 percent slopes Map Unit Setting National map unit symbol: 56tb Elevation: 4,300 to 5,200 feet Mean annual precipitation: 15 to 19 inches Mean annual air temperature: 39 to 45 degrees F Frost-free period: 90 to 110 days Farmland classification: Prime farmland if irrigated Map Unit Composition Turner and similar soils: 85 percent Minor components: 15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Turner Setting Landform: Stream terraces Down-slope shape: Linear Across-slope shape: Linear Parent material: Alluvium Typical profile A - 0 to 6 inches: loam Bt - 6 to 12 inches: clay loam Bk - 12 to 26 inches: clay loam 2C - 26 to 60 inches: very gravelly loamy sand Properties and qualities Slope: 0 to 2 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Well drained Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: About 48 to 96 inches Frequency of flooding: None Frequency of ponding: None Calcium carbonate, maximum in profile: 15 percent Salinity, maximum in profile: Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm) Available water storage in profile: Low (about 5.4 inches) Interpretive groups Land capability classification (irrigated): 3e Land capability classification (nonirrigated): 3e Hydrologic Soil Group: B Ecological site: Loamy (Lo) LRU 44B-B (R044BB032MT) Hydric soil rating: No Custom Soil Resource Report 15 Minor Components Meadowcreek Percent of map unit: 5 percent Landform: Stream terraces Down-slope shape: Linear Across-slope shape: Linear Ecological site: Subirrigated (Sb) 15-19" p.z. (R044XS359MT) Hydric soil rating: No Beaverton Percent of map unit: 5 percent Landform: Alluvial fans, stream terraces Down-slope shape: Linear Across-slope shape: Linear Ecological site: Shallow to Gravel (SwGr) 15-19" p.z. (R044XS354MT) Hydric soil rating: No Turner Percent of map unit: 5 percent Landform: Stream terraces Down-slope shape: Linear Across-slope shape: Linear Ecological site: Silty (Si) 15-19" p.z. (R044XS355MT) Hydric soil rating: No 510B—Meadowcreek loam, 0 to 4 percent slopes Map Unit Setting National map unit symbol: 56vt Elevation: 4,200 to 5,950 feet Mean annual precipitation: 12 to 18 inches Mean annual air temperature: 39 to 45 degrees F Frost-free period: 90 to 110 days Farmland classification: Prime farmland if irrigated Map Unit Composition Meadowcreek and similar soils: 85 percent Minor components: 15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Meadowcreek Setting Landform: Stream terraces Down-slope shape: Linear Across-slope shape: Linear Parent material: Alluvium Custom Soil Resource Report 16 Typical profile A - 0 to 11 inches: loam Bg - 11 to 25 inches: silt loam 2C - 25 to 60 inches: very gravelly sand Properties and qualities Slope: 0 to 4 percent Depth to restrictive feature: More than 80 inches Natural drainage class: Somewhat poorly drained Capacity of the most limiting layer to transmit water (Ksat): Moderately high to high (0.57 to 1.98 in/hr) Depth to water table: About 24 to 42 inches Frequency of flooding: None Frequency of ponding: None Salinity, maximum in profile: Nonsaline to slightly saline (0.0 to 4.0 mmhos/cm) Available water storage in profile: Low (about 5.1 inches) Interpretive groups Land capability classification (irrigated): 2e Land capability classification (nonirrigated): 3e Hydrologic Soil Group: C Ecological site: Subirrigated (Sb) LRU 44B-Y (R044BY150MT) Hydric soil rating: No Minor Components Blossberg Percent of map unit: 10 percent Landform: Terraces Down-slope shape: Linear Across-slope shape: Linear Ecological site: Wet Meadow (WM) 15-19" p.z. (R044XS365MT) Hydric soil rating: Yes Beaverton Percent of map unit: 5 percent Landform: Alluvial fans, stream terraces Down-slope shape: Linear Across-slope shape: Linear Ecological site: Shallow to Gravel (SwGr) 15-19" p.z. (R044XS354MT) Hydric soil rating: No Custom Soil Resource Report 17 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/national/soils/?cid=nrcs142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ home/?cid=nrcs142p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 18 United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/soils/scientists/?cid=nrcs142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/? cid=nrcs142p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf Custom Soil Resource Report 19 Appendix G Administrative Waiver of Groundwater Separation to Stormwater Facility (406) 586-5599 714 Stoneridge Drive, Suite 3 Bozeman, MT 59718 Page 1 November 13, 2025 ATTN: Alicia Paz-Solis City of Bozeman Engineering Department 20 E. Olive St. Bozeman, MT 59715 Re: Rocky Mountain Flats, Bozeman, MT Waiver Request from City of Bozeman Design & Construction Standards Sec. 6.8.3.A.d Dear Alicia, This letter and the enclosed exhibits have been prepared as a waiver request from COB DCS Sec. 6.8.3.A.d for the Rocky Mountain Flats project. This section of the city standards requires stormwater infiltration basins to be a minimum of 2 feet above the estimated seasonal high groundwater table to allow for infiltration of stormwater. Due to the existing site constraints explained below, this 2-foot minimum separation cannot be met for two of the proposed stormwater facilities, so we are seeking a waiver from the standard. This waiver request applies to the two retention ponds representing Storm System #6 and Storm System #9, as well as the Retention Ponds #2-1 and #2-1. All other stormwater facilities on site meet the required 2’ groundwater separation. BACKGROUND The property is largely comprised of open field that was historically in agricultural use. The property generally slopes from south to north at approximately 1.5-2% and is in an area of town that is known to have a high seasonal groundwater table. Groundwater monitoring was performed on the property from April to August 2022 and the results indicate that seasonal high groundwater (SHGW) peaked in early June at depths of approximately 2.5’-3.5’ bgs. Fowler Lane bounds the property to the west, and Meah Lane and S 31st Ave are stubbed to the property to the southeast. Edgerton Ave and Gabriel Ave (local streets) were constructed to the north of the project site as part of the adjacent Buffalo Run Development, and currently dead end at the northern property boundary. All of these street sections will either be widened or extended into the property as part of the proposed project. Edgerton and Gabriel will extend south, upgradient to connect to the extension of Meah Lane. Since the site slopes from south to north, runoff from Gabriel and Edgerton will flow toward the northern property boundary and will need to be captured for treatment. These two locations, the stormwater on Edgerton Page 2 (System #6) and Gabriel (System #9), are where designing storm systems 2’ above the SHGW table is unrealistic. Two additional overflow retention ponds (#2-1 and #2-2) on the northern property line are not set 2’ above SHGW either. These ponds are directly adjacent to the property line, so their rim elevations were set so they could be graded to tie into existing grade at the property line. Since the SHGW elevation in this location is approximately 2’ below existing grade, the bottom of pond elevations would need to be set at the property boundary elevation in order to maintain 2’ separation to SHGW, which is not realistic. These two ponds are only designed to provide overflow capacity during the 100-year storm event, and will not receive runoff during minor storm events. The drainage areas contributing to these ponds have a series of Stormtech chambers that are set 2’ above SHGW to treat the 10-year minor storm event. The COB DCS allows stormwater runoff from the 100-yr event to pond in parking lots and other areas on site and does not specify that this overflow ponding needs to be 2’ above SHGW. Therefore, we do not believe that a waiver request is necessary for these overflow ponds, but they have been included in this request anyway. PROBLEM DEFINED The south ends of both the Edgerton Ave and Gabriel Ave street sections at the northern property line were constructed to approximately the same elevation as the adjacent ground/pasture. In this area, groundwater monitoring results indicate that the SHGW table is approximately 3.5’ below grade at the connection to Edgerton and only approximately 2.5’ below grade at the connection to Gabriel. Since the road surfaces were installed to existing grade, this places SHGW approximately 3.5’ and 2.5’ below the existing asphalt surface of these respective streets at the northern property line. In order for curb inlet structures to be constructible and meet city standards, the minimum height from the curb gutter to the invert out of the structure for a 12” pipe is approximately 2.5’. Therefore, before accounting for any pipe slope, the pipe inverts of structures at these road connections would be at SHGW level on Gabriel and 1’ above SHGW on Edgerton. This means that ponds accepting runoff from curb inlets at these locations would not be able to be constructed above SHGW, and certainly not 2’ above SHGW. Fortunately, according to the stormwater design report for the Buffalo Run Development, the existing storm sewer systems that serve Edgerton and Gabriel to the north of the project site each have a small amount of additional capacity to allow them to accommodate additional street runoff. This allows the inlets in Edgerton and Gabriel for this project to be shifted south of the property line and further up slope, allowing separation of the ponds from SHGW. Shifting these inlets south while placing the ponds on the property line downslope of the inlets, allowed the inlet pipes to slope down to the ponds while keeping the ponds above the seasonal high groundwater table. Refer to the storm plan and profiles in the attached Exhibits for reference of the relationship between the inlets, storm sewer pipes, the ponds, and the groundwater table. The inlets were shifted as far south on the streets as they could be shifted without exceeding the extra capacity that was available in the existing systems to the north. This resulted in the inlets in Edgerton being shifted approximately 83’ south of the property line while the inlets in Gabriel were shifted approximately 105’ south of the property line. With the inlets at these locations and their outlet pipes Page 3 running to the ponds at 0.50% minimum slope, the receiving ponds are both able to be set slightly above the estimated SHGW table. DESIGN ALTERNATIVES Since the receiving inlets cannot be shifted any farther south (uphill) on the streets, and the receiving storm sewer pipes are set as shallow as possible, the only remaining option to raise the ponds to be 2’ above the SHGW table would be to raise the roads at the locations of these inlets. Storm System (Pond) #6 serving Edgerton is 0.40’ above SHGW, while Storm System (Pond) #9 serving Gabriel is 0.20’ above SHGW. So, these ponds would need to be raised by approximately 1.6’ and 1.8’ respectively to meet the 2’ minimum requirement. It can be assumed that in order to gain this additional elevation, the roads would need to be raised a corresponding amount at the inlets. Raising these roads by this much while still tying into the existing street sections at the property lines creates an unrealistic centerline grade on the streets that does not meet city design standards for vertical curves or grade changes. The red line on the road profiles in the exhibits shows an example of a centerline profile that would be needed to raise the road by the required amount at the storm inlets while tying in to the existing street stubs. Since the Buffalo Run development to the north is a dense, multi-family development with walkways, drive approaches, and buildings connecting to or directly adjacent to these streets, we don’t believe that demolishing and re-grading portions of the existing streets to raise the street connections at the property line would be a realistic option. Lastly, the ponds on the northern property lines need to be able to be graded to tie into existing and adjacent grade at the property line. So, even if the roads and ponds could be raised, the ponds would end up “perched” above the existing grade at the property lines. For these reasons, we feel that setting the ponds above SHGW, but not 2’ above SHGW is the most realistic alternative. ADMINISTRATIVE WAIVER REVIEW CRITERIA Following are responses to the three criteria outlined in Section 1.9.2 of the COB DCS that are used to evaluate a waiver request: A. The deviation from standards is not in conflict with applicable state and federal codes and requirements. Although general “industry guidance” recommends a setting stormwater facilities above groundwater, there is not, to our knowledge, a state or federal code that sets a specific minimum separation from groundwater. In fact, until last year, the City design standards did not include a minimum separation of stormwater facilities from groundwater. Therefore, any previous project in the city that applied for a site plan application prior to January 2024 was able to set stormwater facilities within 2’ of Page 4 the water table as we are proposing in this waiver. If this site plan application had been submitted less than a year earlier, a waiver request from this standard would not be required for this design. B. The deviation from standards will not harm, or will be beneficial to, the public in general. This deviation is not expected to harm the public. Since the city did not have this requirement in their previous standards last year and since groundwater is extremely high across most of the city, the majority of stormwater facilities in the city are within 2’ of the water table. This waiver would simply allow these several stormwater facilities to be installed in a similar manner to the majority of systems in the city and in accordance with the old standards instead of meeting the new standard. C. The deviation from standards is consistent with the general purpose of standards to protect public health and safety and promote operational efficiency while minimizing life-cycle costs of public infrastructure. Yes, the deviation is consistent with the general purpose of standards for all the above reasons. As explained previously, receiving this deviation would allow the streets to be graded in a way that meets city design standards for vertical geometry, which were put in place to protect public health and safety. The stormwater facilities as proposed would be installed in a similar configuration as stormwater facilities across the city were installed up until last year. To our knowledge, the majority of the stormwater facilities in the city that are currently constructed in this manner are not a risk to public health and safety. The recently received city comments on the site plan application indicated that the city does not intent to accept maintenance responsibilities for these facilities. So, since these facilities will be privately maintained, minimization of life cycle costs for public infrastructure is not a concern for this deviation. Even if these facilities do switch to being maintained by the city in the future, they are shallow stormwater ponds, so maintenance of them is relatively simple, regardless of their proximity to the water table. SUMMARY Lastly, it should be noted that the remainder of the project design adheres to the new COB DCS stormwater standards, and the developer and the design team has gone to great expense to ensure these standards are met. With the exception of the few stormwater ponds located at the property line, the remainder of the stormwater facilities proposed on the project, serving both the private and public improvements, are set 2’ above SHGW. These facilities are almost all located within parking lots in front of the buildings in low profile Stormtech chamber systems. Since they are under parking lots, setting these facilities 2’ above SHGW has required the parking lots to be designed, on average, 2’-3’ above existing grade and the adjacent buildings to be set anywhere from 3’-7’ above existing grade. In short, requiring the stormwater facilities to be 2’ above SHGW is resulting in almost entire site (roads, buildings, and parking lots) being Page 5 raised by 2’. The requirement to retain the 100-year storm event on site has also resulted in significant increases to the sizes of the proposed stormwater facilities. Adherence to the just these two new stormwater standards alone is resulting in of hundreds of thousands of dollars in cost increases to an affordable housing project. We are aware that cost to the developer is not something that can be considered when reviewing a waiver request. However, we feel it is important to point out that the applicant is not requesting this waiver in order to cut costs. The new standards are being met anywhere on site where it is feasible, regardless of the cost to the project. Instead, the reason for this waiver is to allow the applicant to capture the required amount of stormwater on site while connecting to existing street stubs that were set too low to allow a stormwater design that meets current standards. The elevation of these existing street stubs were reviewed and approved by the city under the old standards, so we feel it is appropriate that the city allow this waiver so we can connect to them with a stormwater design that also meets the old standards. Sincerely, Ethan Cote, PE Alpine Surveying & Engineering, Inc. 15S6W16W16W16W16W16W16W16W SS WS SSWS 6W15S15S15S15S15S15S15S15SE E E EE E E E E GNG BP UTILUTILUTILBP BP BPBPBPBP BP BP BPBPBPBPUTILUTIL UTIL UTIL UTILUTILUTILUTIL D D D D D 18SD18SD18SD18SD18SD18SDD WS WSWSFIRE FIRE FIREWS WSWSFIRE FIREFIRE WS 8W8W8W8W8W8W8W8WDYHDYHDYH 8W 8W 8W 8W 8W 8W8W8W8W8W8W8W8W8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W 8W8W8W8W8W8W8W8W8W8WDYHDYH 8W8W8W8W8W8W8W8W8W8W8W8W8W 8W 8W 8W S 8S8S8S8S8S8S8S8S8S8S8S8S8S8S8SS S S S SSS SS8S8S8S8S8S8S8S8SSS8S8S8S8S8S 8S 8S 8S co co S 8''W16''W16''W8''W 8''W 8''W 8''W 8''W 8''W 8''SS8''W8''W 8''W 8''W 8''W8''W8''W8''W8''W8''SS<><>SSW VW VW V HY DW V W VW VW V W V W VHY DHYDHYD15''SS15''SS15''SS15''SS15''SS15''SSGASGASGASGASCO STSTSTSTCO CO ST DSDSDS DS DS DS DS DS DS DS DS DS DS DS DSDSDS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS DS ST ST ST ST ST ST ST ST ST ST STSTSTST STSTSTSTELECELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC ELEC 8''SS8''SS8''SS8''SS8''SS8''W8''W8''W8''W8''W8''W8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W8''W8''W8''W8''W16''W16''W16''W16''W8''SS8''SS8''SS8''SS8''SSW V W V W V W V W VW VW V W V SS SS W VHYDHYD HYDHY DW V W VW V SS SS SS ST ST STSTST S T STST ST STSTSTW V W V W V W V W VW V ST 15''SS15''SS15''SS15''SS15''SSWBO HYDGASGASGASGASGASGASOSW W VWBO WBO WBO WBO WBO WBO W VW VELEC WBOWBO STORMTECH CHAMBER #2-1 MODEL: SC160LP BOTTOM OF SYSTEM STONE: 5007.10 SHGW: 5004.80 SEPARATION TO GW: 2.30 100-YR PONDING ELEV: 5010.12 STORMTECH CHAMBER #2-2 MODEL: SC160LP BOTTOM OF SYSTEM STONE: 5006.10 SHGW: 5003.90 SEPARATION TO GW: 2.20 100-YR PONDING ELEV: 5010.12 STORMTECH CHAMBER #1 MODEL: SC160LP BOTTOM OF SYSTEM STONE: 5007.50 SHGW: 5005.50 SEPARATION TO GW: 2.00 100-YR PONDING ELEV: 5011.80 OVERFLOW RETENTION POND #2-2 TOP: 5006.50 BOTTOM: 5005.00 GW: 5004.90 SEPARATION TO GW: 0.10 100-YR PONDING ELEV: 5006.50 STORMTECH CHAMBER #3 MODEL: SC160LP BOTTOM OF STONE: 5009.30 GW: 5007.30 SEPARATION TO GW: 2.00 100-YR PONDING ELEV: 5013.60 STORMTECH CHAMBER #8 MODEL: SC160LP BOTTOM OF STONE: 5009.70 GW: 5007.65 SEPARATION TO GW: 2.05 100-YR PONDING ELEV: 5013.60 STORMTECH CHAMBER #5 MODEL: SC160LP BOTTOM OF SYSTEM STONE: 5007.90 SHGW: 5005.90 SEPARATION TO GW: 2.00 100-YR PONDING ELEV: 5011.80 STORM SYSTEM #10 (SWALES) TOP:VARIES BOTTOM (LOWEST SWALE): 5013.65 GW:5010.60 SEPARATION TO GW: 3.05 100-YR PONDING ELEV: 5013.10 STORM SYSTEM #6 (RETENTION POND) ELEVATIONS: 5005.40 (TOP) 5003.90 (BOTTOM) SHGW ELEV: 5003.50 SEPARATION TO GW: 0.40 100-YR PONDING ELEV: 5005.40 12" CULVERT TO HYDRAULICALLY CONNECT PONDS STORM SYSTEM #9 (RETENTION POND) TOP: 5008.00 BOTTOM: 5006.80 GW: 5006.60 SEPARATION TO GW: 0.20 100-YR PONDING ELEV: 5008.00 STORM SYSTEM #8 (RETENTION POND) TOP: 5013.15 BOTTOM: 5012.25 GW: 5010.10 SEPARATION TO GW: 2.15 100-YR PONDING ELEV: 5013.10 OVERFLOW RETENTION POND #2-1 TOP: 5006.50 BOTTOM: 5005.00 GW: 5004.90 SEPARATION TO GW: 0.10 100-YR PONDING ELEV: 5006.50 STORM SYSTEM #4 (LID POND) ELEVATIONS: 5007.20 (TOP) 5005.70 (BOTTOM) SHGW ELEV: 5003.50 SEPARATION TO GW: 2.20 100-YR PONDING ELEV: 5007.20 GABRIEL AVEMEAH LANEEDGERTON BLVDFOWLER LANEMEAH LANE S 31st AVESTORMTECH CHAMBER #7 MODEL: SC160LP BOTTOM OF STONE: 5007.10 GW: 5005.00 SEPARATION TO GW: 2.10 100-YR PONDING ELEV: 5010.12 BLDG C F.F.E.:5014.60 BLDG B F.F.E.:5013.40 BLDG A F.F.E.: 5012.80 F.F.E.: 5008.88 F.F.E.: 5009.08 F.F.E.: 5009.08 F.F.E.: 5008.68 F.F.E.: 5008.88 F.F.E.: 5009.68 STORMTECH CHAMBER #2-3 MODEL: SC160LP BOTTOM OF STONE: 5009.00 GW: 5007.00 SEPARATION TO GW: 2.00 100-YR PONDING ELEV: 5012.40 0 50'100' SCALE 1" = 50' N ROCKY MOUNTAIN FLATS GROUNDWATER SEPARATION FIGURE BOZEMAN, MT EXHIBIT A DATE: 11/13/2025 PROJECT NO: 749-01 BUFFALO RUN (EXISTING) ELECELECELECGASGASGASELEC ELEC ELEC CO CO DSDS DS DS DSSTSTSTST 8''SS8''SS8''SS8''W8''W8''W8''W8''WSS ST ST ST ST ST STSTST ST 8''SS 8''SS W V FW V 8''SS ST GASGASGASGASGAS8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''W8''W6''W8''SSW VW VHYD15''SS15''SS15''SS15''SS15''SS15''SSGASUGPUGPUGPUGPUGPUGP UGP UGP UGP UGP UGP UGP UGP UGP UGP UGP ST0+00 1+00 2+00 3+00 4+004+41 INSTALL FES INV OUT:5004.00 STA: 2+29.40 ST 6-1 (PC) (36"x2') STA: 4+36.1 OFF:0.0'R TBC: 5008.42 RIM: 5007.91 INV OUT: 5005.30 (12")(W) ST 6-2 (PC) (4.0') STA: 4+03.0 OFF:0.2'R TBC: 5008.46 RIM: 5007.95 INV IN: 5005.14 (12")(E) INV OUT: 5004.89 (15")(NW) ST 6-3 (PC) (4.0') STA:3+45.4 OFF:0.0R RIM:5008.05 INV IN:5004.60 (15")(SE) INV OUT:5004.60 (15")(W)500850095008 500 9 5005 5006 5007 5008 5009 500 7 5 0 0 8 PROPOSED STORMWATER EASEMENT STORM SYSTEM #6 (RETENTION POND) TOP OF POND ELEV:5005.40 BOT OF POND ELEV:5003.90 APPROX. S.H.G.W. ELEV.:5003.50 4H:1V SIDE SLOPES W/ 1.5' WATER DEPTH EX. 35' LOCAL STREET LOCAL STREET TO BE SAW CUT AND EXTENDED SOUTH INTO SITE. CURB LIP AT ENDS OF EX STREET SECTION (EA SPOT GRADE) WERE CONSTRUCTED AT APPROXIMATE GRADE OF ADJACENT FIELD. SEASONAL HIGH GROUNDWATER ELEVATION (GW SPOT GRADE) IS ~3.5' BELOW EXISTING GRADE IN THIS AREA 5007 50085007(6.58 EA) (3.17 GW)[6.68][6.78][6.35][6.26][6.62] (6.80 EA) (3.17 GW) EX. GRADE AT PROPERTY LINE (TYP.)-2.9% -2 . 0% (6.98 EA) 83' (8.21 EA) 4995 5000 5005 5010 5015 4995 5000 5005 5010 5015 0+505006.195003.901+005006.095003.901+505006.455003.902+005006.415003.902+505006.275007.323+005006.595007.603+505007.045008.114+005007.745008.42PROPOSED GRADE EXISTING GRADE 8" PVC SAN. SEWER CROSSING. MAINTAIN 12" MIN. SEPARATION 8" PVC SAN. SEWER CROSSING. MAINTAIN 12" MIN. SEPARATION 8" PVC WATER CROSSING. MAINTAIN 18" MIN. SEPARATION 116' of 15" RCP PIPE @ 0.52% 58' of 15" SDR 35 @ 0.50% 33' of 12" SDR 35 @ 0.50% ST 6-1 (PC) (2'x3') INV OUT:5005.30 (12") (W) STA 4+36.1 (0.0'R) TBC:5008.42 RIM:5007.91 ST 6-2 (PC) (4.0') INV IN:5005.14 (12") (E) INV OUT:5004.89 (15") (NW) STA 4+03.0 (0.2'R) TBC:5008.46 RIM:5007.95 ST 6-3 (PC) (4.0') INV IN:5004.60 (15") (SE) INV OUT:5004.60 (15") (W) STA 3+45.4 (0.0'R) RIM:5008.05 INSTALL FES STA:2+29.40 INV OUT:5004.00 STORM SYSTEM #6 (RETENTION POND) TOP OF POND ELEV:5005.40 BOT OF POND ELEV:5003.90 APPROX. S.H.G.W. ELEV.:5003.50 4H:1V SIDE SLOPES W/ 1.5' WATER DEPTH GW GW GW GW GW GW GW GW GW GW GW GW 2.6' SEASONAL HIGH GW TABLE 0.40' 20'0 40' SCALE 1" = 20' N STORM SEWER - EDGERTON1SCALE: HORIZONTAL 1"=20' VERTICAL 1"=2' PROJECT NO: DATE: ENGINEER: REVISIONS DATENO.DESC. SHEET OF 749-01 9/12/2025 ELC 1 2 3 4 5 6 7 8 ROCKY MOUNTAIN FLATSCITY OF BOZEMAN, MONTANAWAIVER REQUEST EXHIBIT4EDGERTON AVEBUILDING A BUILDING BFOWLER LANEEX. 1EDGERTON AVENUE STORMWATER1 -INLETS SET AS FAR NORTH AS POSSIBLE TO CAPTURE AS MUCH STREET AS POSSIBLE AND STILL BE ABLE TO CONVEY WATER TO A POND THAT IS ABOVE THE SHGW TABLE. -ANY INLETS INSTALLED NORTH OF THIS POINT WILL NOT BE ABLE TO DAYLIGHT TO A POND OR SUBSURFACE SYSTEM THAT IS ABOVE THE SHGW TABLE. PIPES AT MINIMUM SLOPE TO CONVEY DESIGN STORM TO POND WHILE KEEPING POND AS HIGH AS POSSIBLE ABOVE WATER TABLE ℄ GRADE OF EX. STREET = 0.60% PER SURVEY -STORMWATER FROM THE STREET SECTION NORTH OF INLETS WILL FLOW NORTH TO INLETS AND SYSTEM INSTALLED WITH BUFFALO RUN PROJECT. BASED ON CAPACITIES SPECIFIED IN BUFFALO RUN DESIGN REPORT, THE EXISTING INLETS AND SYSTEM IN BUFFALO RUN ONLY HAD EXTRA CAPACITY TO SUPPORT ~85 LF OF ADDITIONAL STREET. -STREET AT THIS LOCATION WOULD NEED TO BE RAISED BY ~1.6' TO ALLOW INLETS TO DRAIN TO POND SET 2' ABOVE SHGW. THIS WOULD RESULT IN A ROAD SLOPE OF ~4.6% NORTH OF THESE INLETS, TYING INTO THE EXISTING STREET STUB THAT IS SLOPED AT 0.60%. ELECELECCO 8''W8''W8''W8''W8''W8''W8''SS8''SS8''SS8''SS8''SS8''SSSS ST STSTSTST4''W W V W V 8''SS 8''W 8''W 8''W 8''W 8''W 8''W 8''W 8''WW V HY DUGP UGP UGP UGP UGP UGP UGP UGP UGPUGP0+00 1+001+80 STORM SYSTEM #9 (RETENTION POND) TOP OF POND ELEV:5008.00 BOT OF POND ELEV:5006.80 APPROX. S.H.G.W. ELEV.:5006.60 4H:1V SIDE SLOPES W/ 1.2' WATER DEPTH ST 9-2 (PC) (4.0') STA: 0+39.8 OFF:0.0' TBC: 5010.71 RIM: 5010.20 INV IN: 5007.53 (12")(W) INV OUT: 5007.33 (15")(N) ST 9-1 (PC) (24"x3') STA: 0+06.3 OFF:0.0' TBC: 5010.73 RIM: 5010.22 INV OUT: 5007.70 (12")(E) INSTALL FES INV OUT:5006.85 STA: 1+31.39 5010 5009 5011 5010 5007 5007 5008 5008 5009 5011 SLOPE CONC. CHASE @ -1.5% PROPOSED STORMWATER EASEMENT 18" WIDE CONC. CURB CHASE PER DETAIL 4/C9.3 (8.00) (6.82) (8.25) (8.58 EA) (6.13 GW) (8.07 EA) (5.98 GW) 104' EX. 35' LOCAL STREET EX. GRADE AT PROPERTY LINE (TYP.) [8.35][7.99][8.73] 4995 5000 5005 5010 5015 4995 5000 5005 5010 5015 0+505009.735010.511+005009.015009.411+505008.385006.80PROPOSED GRADE EXISTING GRADE ST 9-2 (PC) (4.0') INV IN:5007.53 (12") (W) INV OUT:5007.33 (15") (N) STA 0+39.8 (0.0') TBC:5010.71 RIM:5010.20 ST 9-1 (PC) (3'x2') INV OUT:5007.70 (12") (E) STA 0+06.3 (0.0') TBC:5010.73 RIM:5010.22 33' of 12" SDR 35 @ 0.50% 92' of 15" SDR 35 @ 0.52% INSTALL FES STA:1+31.39 INV OUT:5006.85 STORM SYSTEM #9 (RETENTION POND) TOP OF POND ELEV:5008.00 BOT OF POND ELEV:5006.80 APPROX. S.H.G.W. ELEV.:5006.60 4H:1V SIDE SLOPES W/ 1.2' WATER DEPTH GW GW GW GW GW 2.5' SEASONAL HIGH GW TABLE 0.20' PROJECT NO: DATE: ENGINEER: REVISIONS DATENO.DESC. SHEET OF 749-01 9/12/2025 ELC 1 2 3 4 5 6 7 8 ROCKY MOUNTAIN FLATSCITY OF BOZEMAN, MONTANAWAIVER REQUEST EXHIBIT4 STORM SEWER - SYSTEM 92 SCALE: HORIZONTAL 1"=20' VERTICAL 1"=2'GABRIEL AVEBUILDING C 20'0 40' SCALE 1" = 20' N CITY PARK -INLETS SET AS FAR NORTH AS POSSIBLE TO CAPTURE AS MUCH STREET AS POSSIBLE AND STILL BE ABLE TO CONVEY WATER TO A POND THAT IS ABOVE THE SHGW TABLE. -ANY INLETS INSTALLED NORTH OF THIS POINT WILL NOT BE ABLE TO DAYLIGHT TO A POND OR SUBSURFACE SYSTEM THAT IS ABOVE THE SHGW TABLE. PIPES AT MINIMUM SLOPE TO CONVEY DESIGN STORM TO POND WHILE KEEPING POND AS HIGH AS POSSIBLE ABOVE WATER TABLE ℄ GRADE OF EX. STREET ~1% PER SURVEY -STORMWATER FROM THE STREET SECTION NORTH OF INLETS WILL FLOW NORTH TO INLETS AND SYSTEM INSTALLED WITH BUFFALO RUN PROJECT. BASED ON CAPACITIES SPECIFIED IN BUFFALO RUN DESIGN REPORT, THE EXISTING INLETS AND SYSTEM IN BUFFALO RUN ONLY HAD EXTRA CAPACITY TO SUPPORT ~105 LF OF ADDITIONAL STREET. -STREET AT THIS LOCATION WOULD NEED TO BE RAISED BY ~1.8' TO ALLOW INLETS TO DRAIN TO POND SET 2' ABOVE SHGW. THIS WOULD RESULT IN A ROAD SLOPE OF ~5.9% NORTH OF THESE INLETS, TYING INTO THE EXISTING STREET STUB THAT IS SLOPED AT 1%. LOCAL STREET TO BE SAW CUT AND EXTENDED SOUTH INTO SITE. CURB LIP AT ENDS OF EX STREET SECTION (EA SPOT GRADE) WERE CONSTRUCTED AT APPROXIMATE GRADE OF ADJACENT FIELD. SEASONAL HIGH GROUNDWATER ELEVATION (GW SPOT GRADE) IS ~2.5' BELOW EXISTING GRADE IN THIS AREA EX. 2GABRIEL AVENUE STORMWATER2 8''W8''W8''W8''W6''W8''W 8''W 8''SS8''SS8''SS8''SSXXXXXXXXXXXXXXXXXXXXXXXXW VW VHYDGAS GAS UGP UGP UGP UGP UGP UGP UGP UGPELECELECELECELECELECELECELECELECELECELECGASGASGASGASGASGASGASGASGASGAS ELEC ELEC ELEC ELECELECELECCOCODSELECELECELECELECELEC8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''WW VW V W VSSHYDHY DW VW VSSSTSTSTSTSTST8''SS8''SSW VFW V8''SS0+001+002+003+004+005+00STA:4+35.32 STA:1+00.50 LIMIT OF PAVING 50105007. 0 5008.05009.05011.05012.05013.035' LOCAL STREET SECTIONR15'R15'R15'R15'EDGERTON AVE 60' PUBLIC STREET AND UTILITY EASEMENT 100' TRANSITION FROM PROPOSED 2% CROWN TO ≈3% CROWN OF EX. STREET SECTION TO THE NORTH. 5' CONC. SIDEWALK (TYP.) INSTALL DOUBLE GUTTER WITH FILLETS PER DETAIL 1/C9.4 MEAH LANE2' INTEGRAL CONCRETE CURB AND GUTTER PER DETAIL 1/C9.3 INSTALL DOUBLE ADA RAMP PER DETAIL 2/C9.0 WITH TRUNCATED DOME DETECTABLE WARNING SURFACE (TYP.) INSTALL NON-ARTERIAL DRIVE APPROACH PER DETAIL 4/C9.0 SAWCUT EXISTING CURB & ASPHALT EX 35' LOCAL STREET SECTION BUFFALO RUN DRIVE APPROACH AND PARKING LOT 5000 5005 5010 5015 5020 5000 5005 5010 5015 5020 0+505013.541+005012.145012.831+505011.375012.502+005010.605011.442+505009.705010.373+005008.745009.313+505007.785008.254+005007.145007.514+505006.915006.905+00 -0.59% -1.48% 2.00%-2.00% -1.42% -2.12%GRADE BREAK STA = 0+00.00ELEV = 5014.25GRADE BREAK STA = 1+15.50ELEV = 5012.61GRADE BREAK STA = 1+30.00ELEV = 5012.90GRADE BREAK STA = 1+44.50ELEV = 5012.61GRADE BREAK STA = 3+50.00ELEV = 5008.25GRADE BREAK STA = 4+35.25ELEV = 5006.99GRADE BREAK STA = 4+70.51ELEV = 5006.78EXISTING GRADE PROPOSED ℄ GRADE POTENTIAL FUTURE ℄ GRADE EX. STREET ℄ GRADE LIMIT OF EX. PAVING -1.14% -4.9 9 % -1.63%GRADE BREAK STA = 1+44.50ELEV = 5012.61GRADE BREAK STA = 4+35.25ELEV = 5006.99PVI STA: 4+09.20 PVI ELEV: 5007.41 K: 10.00 LVC: 33.57 BVCS: 3+92.41BVCE: 5008.25EVCS: 4+25.99EVCE: 5007.14PVI STA: 3+52.63 PVI ELEV: 5010.23 K: 18.54 LVC: 71.23 BVCS: 3+17.02BVCE: 5010.64EVCS: 3+88.25EVCE: 5008.461.6' K-VALUE DOES NOT MEET STANDARDS TRANSITION SLOPE ℄ GRADE NEEDED TO RAISE INLETS/POND TO PROVIDE 2' SEPARATION TO SHGW 0 30'60' SCALE 1" = 30'NEDGERTON AVENUE PLAN & PROFILE1SCALE: HORIZONTAL 1"= 30' VERTICAL 1"= 3' PROJECT NO: DATE: ENGINEER: REVISIONS DATENO.DESC. SHEET OF 749-01 9/12/2025 ELC 1 2 3 4 5 6 7 8 ROCKY MOUNTAIN FLATSCITY OF BOZEMAN, MONTANAWAIVER REQUEST EXHIBIT4 BUILDING B BUILDING A EX. 3EDGERTON AVENUE PLAN & PROFILE3 8''W8''W8''W8''W8''W8''W8''SS8''SS8''SSXXXXXXXXXXXXXXXXXXXXXXXW VHYDUGPUGPUGPUGPUGPUGP UGP UGP UGP UGP UGP UGP UGP UGPELECELECCODSELEC ELECELECELECELEC8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''W8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SS8''SSW VW VW VSSSSSTST ST ST ST4''WW VW V8''SSELEC HYD0+001+002+003+004+004+61.9750105009.05011.05012.05013.05014.060' PUBLIC STREET AND UTILITY EASEMENTR15'R15'100' TRANSITION FROM PROPOSED 2% CROWN TO ≈3% CROWN OF EX. STREET SECTION TO THE NORTH. 6' CONC. SIDEWALK 2' INTEGRAL CONCRETE CURB AND GUTTER PER DETAIL 1/C9.3 35' LOCAL STREET SECTION INSTALL SINGLE ADA RAMP PER DETAIL 1/C9.0 WITH TRUNCATED DOME DETECTABLE WARNING SURFACE (TYP.) INSTALL NON-ARTERIAL DRIVE APPROACH PER DETAIL 4/C9.0 SAWCUT EXISTING CURB & ASPHALT EX 35' LOCAL STREET SECTION ADJACENT BUILDING ON BUFFALO RUN SITE 5005 5010 5015 5020 5005 5010 5015 5020 0+505013.095014.071+005012.355014.151+505011.645012.962+005010.855011.752+505009.985010.543+005009.175009.403+505008.455008.454+005007.955007.924+50 5+00 -1.91% -0.97% 2.00%-2.00%-0.18% -2.43%GRADE BREAK STA = 0+15.50ELEV = 5014.13GRADE BREAK STA = 0+77.47ELEV = 5014.02GRADE BREAK STA = 0+91.97ELEV = 5014.31GRADE BREAK STA = 1+06.47ELEV = 5014.02GRADE BREAK STA = 2+84.53ELEV = 5009.70GRADE BREAK STA = 3+54.86ELEV = 5008.36GRADE BREAK STA = 4+10.00ELEV = 5007.82STA: 0+91.97MEAH LANE DESIGN CL CROSSINGEXISTING GRADE PROPOSED ℄ GRADE POTENTIAL FUTURE ℄ GRADE EXISTING STREET ℄ GRADE LIMIT OF EX. PAVING -1.06% -5. 9 3 % -1.91%GRADE BREAK STA = 1+06.47ELEV = 5014.02GRADE BREAK STA = 3+54.86ELEV = 5008.36PVI STA: 3+27.55 PVI ELEV: 5008.88 K: 10.00 LVC: 40.18 BVCS: 3+07.46BVCE: 5010.07EVCS: 3+47.64EVCE: 5008.49PVI STA: 2+70.14 PVI ELEV: 5012.28 K: 15.00 LVC: 73.03 BVCS: 2+33.63BVCE: 5012.67EVCS: 3+06.65EVCE: 5010.121.8' K-VALUE DOES NOT MEET STANDARDS TRANSITION SLOPE ℄ GRADE NEEDED TO RAISE INLETS/POND TO PROVIDE 2' SEPARATION TO SHGW EX. 4GABRIEL AVENUE STORMWATER0 30'60' SCALE 1" = 30'N4 GABRIEL AVENUE PLAN & PROFILE1SCALE: HORIZONTAL 1"= 30' VERTICAL 1"= 3' PROJECT NO: DATE: ENGINEER: REVISIONS DATENO.DESC. SHEET OF 749-01 9/12/2025 ELC 1 2 3 4 5 6 7 8 ROCKY MOUNTAIN FLATSCITY OF BOZEMAN, MONTANAWAIVER REQUEST EXHIBIT4 GABRIEL AVENUEMEAH LANEBUILDING C CITY PARK