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HomeMy WebLinkAboutAPPENDIX E_StormDrainageReportTHE HOMESTEAD AT BUFFALO RUN STORM WATER DESIGN REPORT _________________________________________________________________________ Page 2 of 11 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 ........................................................................................................ 5 5 Methodologies .................................................................................................................... 5 5.1 Design Methodology .................................................................................................... 5 5.2 Design Storm Analyses ................................................................................................ 5 5.3 Storm Drain Piping ....................................................................................................... 5 5.4 Storm Water Treatment Facilities ................................................................................. 8 5.5 Overflow .....................................................................................................................10 6 Maintenance ......................................................................................................................11 7 Conclusions .......................................................................................................................11 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 _________________________________________________________________________ Page 3 of 11 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 will be designed and 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-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 and is annexation into the City of Bozeman. See Exhibit A for location details. Buffalo Run Bozeman, LLC plans to construct a 237-unit multi-family apartment community and a clubhouse as part of this development. 2.2 Development Horizon The project will begin development a soon as the entitlement approvals are in place, tentatively scheduled for 2021/2022. 3 EXISTING AREA CONDITIONS 3.1 Existing Land Cover and Slopes The existing property is primarily vacant, agricultural land. The existing slopes range from 0% to 4%, generally draining 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 an existing pond and irrigation ditch that bisects the property. The irrigation ditch along Fowler Lane will be channelized or piped depending on project requirements through the required city-standard road section. Based on road grades required for Fowler Lane, the ditch will be realigned and grade adjustments made to ensure adequate flow is provided for the existing water rights users. Additionally, the two ditches on each side of the road next to the property will be combined through the city-standard section next to the Buffalo Run property. This will allow water and sewer utilities to be installed while maintaining separation and establishing the west side of the ditch as the future location for this facility as development progresses in the area. A control structure will be installed to permit the flows to _________________________________________________________________________ Page 4 of 11 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT be divided downstream of the property and redirect some of the water to the east side of the property to allow water rights users to access it east of Fowler Lane. Additional consideration was given to potential offsite stormwater run-on into the existing ditches to ensure that capacity is sufficient and no properties are inundated during storm events while irrigating. The seepage ditch that feeds the existing pond will remain. Most of the ditch within the property will be conveyed via pipe to the existing outfall located on the project to the north. Flow rate capacity within the ditch will be maintained to prevent restrictions on water rights holders to that water downstream of the property while preventing any flow restrictions or deleterious impacts upstream. Contact has been made with the ditch companies and owners that have vested water rights for the irrigation waters discussed above. Negotiations for an agreement for alteration/construction of these facilities and future maintenance will be executed. 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. Ponds designated onsite were designed with sufficient storage to retain the entire stormwater volume from contributing stormwater basins. The contributing 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 vicinity. One irrigation ditch lies within east side of the existing Fowler Lane easement. An additional ditch bisects the property. Both ditches will be realigned as part of this project. All proposed development will maintain a minimum 50 ft setback from the designated wetland boundary. _________________________________________________________________________ Page 5 of 11 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT 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 seventeen (17) major drainage basins based on the receiving treatment facility. The basins are further subdivided into a total of 29 subbasins to evaluate gutter spread and inlet capture for each sub-basin. The only areas that could not be captured included basins X-1, X-2N, and X-3N due to site constraints with tie-ins to existing grades and limitations base on groundwater levels. These areas were minimized as much as 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. 5 METHODOLOGIES This section documents the methodologies and assumptions used to conduct the storm water runoff analyses for the proposed development. 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 subsurface treatment facilities, convey, and treat storm water runoff. Summaries of runoff estimates, inlet and piping capacities, and retention volumes are provided in the sections that follow. 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 a excel spreadsheets for time of concentration, peak flows, and retention volumes, pipe flows and velocities, and inlet gutter spread calculations. Detailed calculations are included in Appendix C. 5.3 Storm Drain Piping 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). The 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 required velocities during the 25-year design storm at the beginning of the reaches. Slopes were increased as much as feasible to increase velocities while maintaining required cover depths at the required minimum pipe sizes. _________________________________________________________________________ Page 6 of 11 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT 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: Table 1: Basin Peak Flow and Capture Summary Sub-basin Basin Peak Flow (cfs) Runon (cfs) Comb. Peak Flow (cfs) Capture Facility # of Inlets Spread at / upstream of Capture Facility (ft) Capt. Flow (cfs) Byp. Flow (cfs) Bypass Dest. F-1 1.05 0.00 1.05 INLET - GRADE 1 4.87 0.78 0.27 OFFSITE F-2 1.51 0.00 1.51 INLET - GRADE 1 5.68 1.03 0.48 OFFSITE K-1N 0.45 0.00 0.45 INLET - GRADE 1 3.46 0.39 0.06 OFFSITE K-1S 0.55 0.00 0.55 INLET - GRADE 1 4.00 0.46 0.09 OFFSITE K-2 0.48 0.00 0.48 INLET - SAG 1 2.90 0.48 0.00 NONE K-3 0.79 0.00 0.79 INLET - SAG 1 4.08 0.79 0.00 NONE K-4 0.65 0.00 0.65 INLET - SAG 1 3.57 0.65 0.00 NONE K-5 1.04 0.00 1.04 INLET - SAG 1 4.91 1.04 0.00 NONE K-6 0.38 0.00 0.38 INLET - GRADE 1 3.38 0.33 0.04 OFFSITE K-7 0.04 1.00 1.03 INLET - GRADE 1 5.35 0.77 0.27 OFFSITE KB-1 1.99 0.29 2.28 INLET - SAG 1 8.34 2.28 0.00 NONE KB-2 2.31 0.09 2.40 INLET - SAG 1 4.08 2.40 0.00 NONE KC-1 1.94 0.55 2.49 INLET - GRADE 1 7.20 1.49 1.00 K-7 _________________________________________________________________________ Page 7 of 11 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Table 1: Basin Peak Flow and Capture Summary Sub-basin Basin Peak Flow (cfs) Runon (cfs) Comb. Peak Flow (cfs) Capture Facility # of Inlets Spread at / upstream of Capture Facility (ft) Capt. Flow (cfs) Byp. Flow (cfs) Bypass Dest. B-1 1.08 0.00 1.08 INLET - GRADE 1 5.30 0.79 0.29 KB-1 B-2 0.55 0.00 0.55 INLET - GRADE 1 3.82 0.46 0.09 KB-2 C-1 1.39 0.00 1.39 INLET - GRADE 1 5.99 0.96 0.43 KC-1 C-2 0.63 0.00 0.63 INLET - GRADE 1 4.25 0.51 0.12 KC-1 PF-1A 2.42 0.00 2.42 INLET - SAG 2 11.70 2.42 0.00 NONE PF-1B 2.08 0.00 2.08 INLET - SAG 2 14.89 2.08 0.00 NONE PF-2 3.69 0.00 3.69 INLET - SAG 3 18.69 3.69 0.00 NONE PF-3A 4.08 0.00 4.08 INLET - SAG 3 22.27 4.08 0.00 NONE PF- 3B 4.15 0.00 4.15 INLET - SAG 3 25.21 4.15 0.00 NONE PF- 4A 5.01 0.00 5.01 INLET - SAG 4 26.32 5.01 0.00 NONE PF- 4B 3.94 0.00 3.94 INLET - SAG 4 21.68 3.94 0.00 NONE P-1 1.21 0.00 1.21 P-1 N/A 1.21 0.00 N/A X-1 0.17 0.00 0.17 N/A - RUNOFF N/A N/A N/A N/A X-2N 0.22 0.00 0.22 N/A - RUNOFF N/A N/A N/A N/A X-2S 0.21 0.00 0.21 N/A - RUNOFF N/A N/A N/A N/A Park 0.45 0.00 0.45 N/A N/A N/A N/A N/A _________________________________________________________________________ Page 8 of 11 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT 5.4 Storm Water Treatment Facilities A majority of stormwater from the site will be treated in subsurface Stormtech® systems. Two areas will provide storm treatment using ponds. An existing pond will provide treatment for a small portion of the site that currently drains to it. The park runoff coefficient is proposed to decrease as the area will be planted and maintained with denser grasses than the current pasture. No facility is required for the park. Storm runoff from the road 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. The remaining stormwater treatment facilities lie within the Buffalo Run property and will be owned and maintained by the property owner in accordance with an operation and maintenance manual. Treatment facilities were designed to store runoff from a 10-year 2-hour event. See the tables below for treatment areas, storage volumes, and elevations. Exhibit B is provided to illustrate major drainage basins, sub-basins, and designated treatment facilities. Ponds shall receive flow through their designated inlet pipes and reinforced concrete flared end sections. Treatment facilities were designed with bottom elevations above the seasonal high ground water level. Proposed pond bottom elevations and estimated high groundwater elevations are specified in Table 3 below. High groundwater elevations are based on data collected at monitoring wells for the project (Appendix B). Table 2: Storm Basin Summary Sub-basin Area (acres) Runoff Coefficient First 1/2" Facility (ft3) Retention Storage (ft3) Treatment Facility Treatment Facility Type F-1 0.27 0.95 474.01 777.38 R-1 STORMTECH F-2 1.71 0.70 2175.78 3568.27 R-1 STORMTECH K-1N 0.18 0.80 255.73 419.40 R-1 STORMTECH K-1S 0.16 0.80 237.13 388.90 R-1 STORMTECH K-2 0.18 0.80 261.70 429.19 R-1 STORMTECH K-3 0.33 0.80 477.33 782.83 R-2 STORMTECH K-4 0.24 0.80 353.17 579.19 R-3 STORMTECH K-5 0.45 0.80 647.97 1062.67 R-3 STORMTECH K-6 0.11 0.80 162.13 265.90 R-3 STORMTECH K-7 0.01 0.80 19.13 31.38 R-3 STORMTECH KB-1 0.90 0.75 1223.78 2007.00 R-1 STORMTECH KB-2 0.27 0.95 474.01 777.38 R-2 STORMTECH KC-1 0.95 0.75 1297.09 2127.23 R-3 STORMTECH B-1 0.36 0.80 523.13 857.94 R-4 STORMTECH B-2 0.34 0.80 487.37 799.28 R-4 STORMTECH C-1 0.51 0.75 688.34 1128.88 R-5 STORMTECH _________________________________________________________________________ Page 9 of 11 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Table 2: Storm Basin Summary Sub-basin Area (acres) Runoff Coefficient First 1/2" Facility (ft3) Retention Storage (ft3) Treatment Facility Treatment Facility Type C-2 0.27 0.80 388.10 636.48 R-5 STORMTECH PF-1A 0.63 0.95 1088.46 1785.08 S-1A STORMTECH PF-1B 0.71 0.85 1092.68 1791.99 S-1B STORMTECH PF-2 1.41 0.90 2301.49 3774.44 S-2 STORMTECH PF-3A 1.59 0.80 2302.73 3776.48 S-3A STORMTECH PF- 3B 1.84 0.85 2841.83 4660.61 S-3B STORMTECH PF- 4A 2.23 0.80 3235.57 5306.33 S-4A STORMTECH PF- 4B 2.38 0.80 3459.33 5673.31 S-4B STORMTECH P-1 1.04 0.70 1324.66 2172.45 POND RETENTION POND X-1 0.09 0.80 136.90 224.52 N/A N/A X-2N 0.06 0.80 93.93 154.05 N/A N/A X-2S 0.06 0.80 92.70 152.03 N/A N/A Park 1.98 0.23 827.23 1356.66 N/A N/A Table 3: Treatment Facility Summary Treatment Facility Type Retention Volume Required (cf) Retention Volume Provided (cf) R-1 STORMTECH 6,357 6,315 R-2 STORMTECH 3,453 3,091 R-3 STORMTECH 3,649 3,916 R-4 STORMTECH 1,298 1,423 R-5 STORMTECH 1,294 1,423 S-1A STORMTECH 1,785 1,838 S-1B STORMTECH 1,792 1,845 S-2 STORMTECH 3,774 3,884 ________________________________________________________________________ Page 10 of 11 THE HOMESTEAD AT BUFFALO RUN – BOZEMAN STORM WATER DESIGN REPORT Table 3: Treatment Facility Summary Treatment Facility Type Retention Volume Required (cf) Retention Volume Provided (cf) S-3A STORMTECH 3,776 3,887 S-3B STORMTECH 4,661 4,715 S-4A STORMTECH 5,306 5,408 S-4B STORMTECH 5,673 5,794 P-1 POND 2,172 6,550 Totals 44,992 43,539 Table 4: Stormwater Facility Bottom Elevation and Groundwater Elevation Treatment Facility Bottom Elevation (ft-amsl) Estimated High Groundwater (ft-amsl) R-1 4,994.41 4,994.33 R-2 4,994.77 4,994.59 R-3 4,995.51 4,994.96 R-4 5,000.73 4,999.75 R-5 5,001.59 5,000.63 S-1A 4,996.71 4,996.04 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 4,998.00 4,997.01 S-4B 4,998.00 4,997.20 P-1 EXISTING 4,999.06 5.5 Overflow The existing pond will include a headwall and gate structure (similar to the existing) to allow stormwater to exit in the case that the capacity is exceeded. ________________________________________________________________________ Page 11 of 11 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. A designated access pathway using concrete grass pavers or concrete slabs within the boulevard and a reinforced concrete access on the interior embankments is proposed for maintenance vehicle access. An Operation and Maintenance Manual is included in Appendix D. 7 CONCLUSIONS Runoff from the Buffalo Run development will be conveyed to subsurface drain structures and utilize an existing pond for storage and treatment. All retention structures, conveyance facilities, and ponds were designed in conformance with the current City of Bozeman Design standards. 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 12S12S12S12S12S12S12S12S12S12S12S12S12S12S12S12S12S12S12S16W16W16W16W16W16W16W16W16W16W16W16W16W16W16WIRR IRR IRR IRR IRR IRRIRRIRRIRRIRR IRR IRR IRR D D D D D D D D D D D D D D S-1A S-1B R-1A S-2 S-4A S-4B R-4 R-3 R-5 S-3A S-3B P-1 R-1B R-2 2021COPYRIGHT © 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 Oct/14/2021 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 10/2021 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) SUBBASIN R-1R-2R-3R-4R-5S-1AS-1BS-2S-3AS-3BS-4AS-4BPARKP-1R-1KURK DRIVE AVENUE BAVENUE CFOWLER LANEX-2NX-2SX-110/14/2021 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 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 THE HOMESTEAD AT BUFFALO RUN SUB-BASIN SUMMARY Sub-basin Area (acres) Runoff Coefficient First 1/2" Facility (ft3) Retention Storage (ft3) Treatment Facility Treatment Facility Type F-1 0.27 0.95 474.01 777.38 R-1 STORMTECH F-2 1.71 0.70 2175.78 3568.27 R-1 STORMTECH K-1N 0.18 0.80 255.73 419.40 R-1 STORMTECH K-1S 0.16 0.80 237.13 388.90 R-1 STORMTECH K-2 0.18 0.80 261.70 429.19 R-1 STORMTECH K-3 0.33 0.80 477.33 782.83 R-2 STORMTECH K-4 0.24 0.80 353.17 579.19 R-3 STORMTECH K-5 0.45 0.80 647.97 1062.67 R-3 STORMTECH K-6 0.11 0.80 162.13 265.90 R-3 STORMTECH K-7 0.01 0.80 19.13 31.38 R-3 STORMTECH KB-1 0.90 0.75 1223.78 2007.00 R-1 STORMTECH KB-2 0.90 0.95 1550.12 2542.20 R-2 STORMTECH KC-1 0.95 0.75 1297.09 2127.23 R-3 STORMTECH B-1 0.36 0.80 523.13 857.94 R-4 STORMTECH B-2 0.34 0.80 487.37 799.28 R-4 STORMTECH C-1 0.51 0.75 688.34 1128.88 R-5 STORMTECH C-2 0.27 0.80 388.10 636.48 R-5 STORMTECH PF-1A 0.63 0.95 1088.46 1785.08 S-1A STORMTECH PF-1B 0.71 0.85 1092.68 1791.99 S-1B STORMTECH PF-2 1.41 0.90 2301.49 3774.44 S-2 STORMTECH PF-3A 1.59 0.80 2302.73 3776.48 S-3A STORMTECH PF-3B 1.84 0.85 2841.83 4660.61 S-3B STORMTECH PF-4A 2.23 0.80 3235.57 5306.33 S-4A STORMTECH PF-4B 2.38 0.80 3459.33 5673.31 S-4B STORMTECH P-1 1.04 0.70 1324.66 2172.45 POND RETENTION POND X-1 0.09 0.80 136.90 224.52 N/A N/A X-2N 0.06 0.80 93.93 154.05 N/A N/A X-2S 0.06 0.80 92.70 152.03 N/A N/A Park 1.98 0.23 827.23 1356.66 N/A N/A N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 1 of 1 THE HOMESTEAD AT BUFFALO RUN TREATMENT FACILITY SUMMARY Treatment Facility Type Retention Volume Required (cf) Retention Volume Provided (cf) R-1 STORMTECH 6,357 6,315 R-2 STORMTECH 3,453 3,091 R-3 STORMTECH 3,649 3,916 R-4 STORMTECH 1,298 1,423 R-5 STORMTECH 1,294 1,423 S-1A STORMTECH 1,785 1,838 S-1B STORMTECH 1,792 1,845 S-2 STORMTECH 3,774 3,884 S-3A STORMTECH 3,776 3,887 S-3B STORMTECH 4,661 4,715 S-4A STORMTECH 5,306 5,408 S-4B STORMTECH 5,673 5,794 P-1 POND 2,172 Totals 44,992 43,539 N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 1 of 1 THE HOMESTEAD AT BUFFALO RUN TREATMENT ELEVATION SUMMARY Treatment Facility Bottom Elevation (ft-amsl) Estimated High Groundwater (ft-amsl) R-1 4,994.41 4,994.33 R-2 4,994.77 4,994.59 R-3 4,995.51 4,994.96 R-4 5,000.73 4,999.75 R-5 5,001.59 5,000.63 S-1A 4,996.71 4,996.04 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 4,998.00 4,997.01 S-4B 4,998.00 4,997.20 P-1 EXISTING 4,999.06 N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 1 of 1 THE HOMESTEAD AT BUFFALO RUNPEAK FLOW AND CAPTURE SUMMARYSub-basinBasin Peak Flow(cfs)Runon(cfs)Combined Peak Flow(cfs)Capture Facility# of InletsSpread at/upstream of Capture Facility(ft)Captured Flow(cfs)Bypassed Flow(cfs)Bypass DestinationF-1 1.05 0.00 1.05 INLET - GRADE 1 4.87 0.78 0.27 OFFSITEF-2 1.51 0.00 1.51 INLET - GRADE 1 5.68 1.03 0.48 OFFSITEK-1N 0.45 0.00 0.45 INLET - GRADE 1 3.46 0.39 0.06 OFFSITEK-1S 0.55 0.00 0.55 INLET - GRADE 1 4.00 0.46 0.09 OFFSITEK-2 0.48 0.00 0.48 INLET - SAG 1 2.90 0.48 0.00 NONEK-3 0.79 0.00 0.79 INLET - SAG 1 4.08 0.79 0.00 NONEK-4 0.65 0.00 0.65 INLET - SAG 1 3.57 0.65 0.00 NONEK-5 1.04 0.00 1.04 INLET - SAG 1 4.91 1.04 0.00 NONEK-6 0.38 0.00 0.38 INLET - GRADE 1 3.38 0.33 0.04 OFFSITEK-7 0.04 1.00 1.03 INLET - GRADE 1 5.35 0.77 0.27 OFFSITEKB-1 1.99 0.29 2.28 INLET - SAG 1 8.34 2.28 0.00 NONEKB-2 2.31 0.09 2.40 INLET - SAG 1 4.08 2.40 0.00 NONEKC-1 1.94 0.55 2.49 INLET - GRADE 1 7.20 1.49 1.00 K-7B-1 1.08 0.00 1.08 INLET - GRADE 1 5.30 0.79 0.29 KB-1B-2 0.55 0.00 0.55 INLET - GRADE 1 3.82 0.46 0.09 KB-2C-1 1.39 0.00 1.39 INLET - GRADE 1 5.99 0.96 0.43 KC-1C-2 0.63 0.00 0.63 INLET - GRADE 1 4.25 0.51 0.12 KC-1PF-1A 2.42 0.00 2.42 INLET - SAG 2 11.70 2.42 0.00 NONEPF-1B 2.08 0.00 2.08 INLET - SAG 2 14.89 2.08 0.00 NONEPF-2 3.69 0.00 3.69 INLET - SAG 3 18.69 3.69 0.00 NONEPF-3A 4.08 0.00 4.08 INLET - SAG 3 22.27 4.08 0.00 NONEPF-3B 4.15 0.00 4.15 INLET - SAG 3 25.21 4.15 0.00 NONEPF-4A 5.01 0.00 5.01 INLET - SAG 4 26.32 5.01 0.00 NONEPF-4B 3.94 0.00 3.94 INLET - SAG 4 21.68 3.94 0.00 NONEP-1 1.21 0.00 1.21 P-1 N/A 1.21 0.00 N/AX-1 0.17 0.00 0.17 N/A - RUNOFF N/A N/A N/A N/AX-2N 0.22 0.00 0.22 N/A - RUNOFF N/A N/A N/A N/AX-2S 0.21 0.00 0.21 N/A - RUNOFF N/A N/A N/A N/APark 0.58 0.00 0.58 N/A N/A N/A N/A N/AN:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm1 of 1 The Homestead at Buffalo Run - Pipe ReportVelocity(ft/s)Percent Full(%)Discharge(cfs)Diameter(in)Channel Slope(ft/ft)Roughness CoefficientFriction MethodSolve ForLabelCategory5.4589.76.3215.00.0050.010Manning FormulaNormal DepthR-1(combined)Roads3.8553.32.5615.00.0030.010Manning FormulaNormal DepthFowler (combined)Roads4.5255.93.1915.00.0040.010Manning FormulaNormal DepthR-2 (combined)Roads4.3751.22.7615.00.0040.010Manning FormulaNormal DepthK2,KB-1,bypass (B-1)Roads3.8438.81.6915.00.0040.010Manning FormulaNormal DepthK-4,K-5Roads3.8653.72.5915.00.0030.010Manning FormulaNormal DepthK-6,K-7,KC-1,BYPASS CRoads4.3349.92.6515.00.0040.010Manning FormulaNormal DepthR-3 (combined)Roads4.1335.81.6315.00.0050.010Manning FormulaNormal DepthR-4 (combined)Roads7.9338.93.5015.00.0170.010Manning FormulaNormal DepthR-5 (combined)Roads5.1057.13.6915.00.0050.010Manning FormulaNormal DepthS-2Site5.2160.94.0815.00.0050.010Manning FormulaNormal DepthS-3ASite5.2361.64.1515.00.0050.010Manning FormulaNormal DepthS-3BSite4.9352.23.1915.00.0050.010Manning FormulaNormal DepthK3,KB-2,bypass (B-2)RoadsPage 1 of 127 Siemon Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-166610/15/2021FlowMaster[10.02.00.01]Bentley Systems, Inc. Haestad Methods Solution CenterThe Homestead at Buffalo Run.fm8 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 11,975 0.275 0.95 0.261 0.95 1.10 1.05 1.00 0.275 Totals 11,975 0.275 0.261 0.275 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 1.4%n/a 0.77 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 631.00 1.6%2.69 3.91 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 5.0 min QRUNON:0.000 cfs QPOST-DEV(BASIN):1.052 cfs QTOTAL:1.052 cfs Inlet Type:Combination QINTERCEPTED:0.776 cfs QBYPASS:0.276 cfs Gutter Spread Width:4.87 ft Depth of Flow in Gutter:2.3 in POST-DEVELOPMENT FLOW RATES INLET CALCULATIONS Buffalo Run | Post-Development Subbasin F-1 - Time of Concentration <= 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.xlsm10/15/2021 1 of 10 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 74,598 1.713 0.70 1.199 0.70 1.10 0.77 0.77 1.319 Totals 74,598 1.713 1.199 1.319 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft)(ft/ft)(ft/2)(min) Sheet Flow 169.30 0.8%n/a 29.99 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 496.00 1.6%2.91 2.84 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 32.8 min QRUNON:0.000 cfs QPOST-DEV(BASIN):1.513 cfs QTOTAL:1.513 cfs Inlet Type:Combination QINTERCEPTED:1.025 cfs QBYPASS:0.488 cfs Gutter Spread Width:5.68 ft Depth of Flow in Gutter:2.6 in Buffalo Run | Post-Development Subbasin F-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 10/15/2021 2 of 10 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 7,672 0.176 0.80 0.141 0.80 1.10 0.88 0.88 0.155 Totals 7,672 0.176 0.141 0.155 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 1.5%n/a 6.51 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 147.00 1.3%2.09 1.17 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 7.7 min QRUNON:0.000 cfs QPOST-DEV(BASIN):0.451 cfs QTOTAL:0.451 cfs Inlet Type:Combination QINTERCEPTED:0.391 cfs QBYPASS:0.059 cfs Gutter Spread Width:3.46 ft Depth of Flow in Gutter:1.8 in Buffalo Run | Post-Development Subbasin K-1N - 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 10/15/2021 3 of 10 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 7,114 0.163 0.80 0.131 0.80 1.10 0.88 0.88 0.144 Totals 7,114 0.163 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 31.00 1.5%n/a 0.90 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 138.00 1.0%1.99 1.16 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 5.0 min QRUNON:0.000 cfs QPOST-DEV(BASIN):0.550 cfs QTOTAL:0.550 cfs Inlet Type:Combination QINTERCEPTED:0.459 cfs QBYPASS:0.091 cfs Gutter Spread Width:4.00 ft Depth of Flow in Gutter:2.0 in Buffalo Run | Post-Development Subbasin K-1S - 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 10/15/2021 4 of 10 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 7,851 0.180 0.80 0.144 0.80 1.10 0.88 0.88 0.159 Totals 7,851 0.180 0.144 0.159 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 1.5%n/a 6.53 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 65.50 0.5%1.45 0.75 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 7.3 min QRUNON:0.000 cfs QPOST-DEV(BASIN):0.477 cfs QTOTAL:0.477 cfs Inlet Type:Sag QINTERCEPTED:0.477 cfs QBYPASS:0.000 cfs Gutter Spread Width:2.90 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 10/15/2021 5 of 10 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 14,320 0.329 0.80 0.263 0.80 1.10 0.88 0.88 0.289 Totals 14,320 0.329 0.263 0.289 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 1.5%n/a 6.51 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 209.00 0.6%1.72 2.03 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 8.5 min QRUNON:0.000 cfs QPOST-DEV(BASIN):0.786 cfs QTOTAL:0.786 cfs Inlet Type:Combination QINTERCEPTED:0.620 cfs QBYPASS:0.166 cfs Gutter Spread Width:5.30 ft Gutter Spread Width:4.08 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 10/15/2021 6 of 10 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 10,595 0.243 0.80 0.195 0.80 1.10 0.88 0.88 0.214 Totals 10,595 0.243 0.195 0.214 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 1.5%n/a 6.51 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 108.00 1.6%2.43 0.74 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 7.2 min QRUNON:0.000 cfs QPOST-DEV(BASIN):0.646 cfs QTOTAL:0.646 cfs Inlet Type:Combination QINTERCEPTED:0.528 cfs QBYPASS:0.118 cfs Gutter Spread Width:3.57 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 10/15/2021 7 of 10 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 19,439 0.446 0.80 0.357 0.80 1.10 0.88 0.88 0.393 Totals 19,439 0.446 0.357 0.393 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft)(ft/ft)(ft/2)(min) Sheet Flow 35.00 1.5%n/a 8.20 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 108.00 1.6%2.68 0.67 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 8.9 min QRUNON:0.000 cfs QPOST-DEV(BASIN):1.041 cfs QTOTAL:1.041 cfs Inlet Type:Combination QINTERCEPTED:0.769 cfs QBYPASS:0.272 cfs Gutter Spread Width:4.91 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 10/15/2021 8 of 10 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 4,864 0.112 0.80 0.089 0.80 1.10 0.88 0.88 0.098 Totals 4,864 0.112 0.089 0.098 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 0.8%n/a 0.80 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 212.00 1.0%1.81 1.95 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 5.0 min QRUNON:0.000 cfs QPOST-DEV(BASIN):0.376 cfs QTOTAL:0.376 cfs Inlet Type:Combination QINTERCEPTED:0.334 cfs QBYPASS:0.042 cfs Gutter Spread Width:3.38 ft Depth of Flow in Gutter:1.8 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 10/15/2021 9 of 10 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 574 0.013 0.80 0.011 0.80 1.10 0.88 0.88 0.012 Totals 574 0.013 0.011 0.012 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft)(ft/ft)(ft/2)(min) Sheet Flow 27.60 1.8%n/a 6.56 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 66.00 1.0%2.23 0.49 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 7.1 min QRUNON:0.998 cfs QPOST-DEV(BASIN):0.036 cfs QTOTAL:1.034 cfs Inlet Type:Combination QINTERCEPTED:0.765 cfs QBYPASS:0.269 cfs Gutter Spread Width:5.35 ft Depth of Flow in Gutter:2.5 in Buffalo Run | Post-Development Subbasin K-7 - 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 10/15/2021 10 of 10 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 39,161 0.899 0.75 0.674 0.75 1.10 0.83 0.83 0.742 Totals 39,161 0.899 0.674 0.742 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft)(ft/ft)(ft/2)(min) Sheet Flow 27.50 3.1%n/a 5.62 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 494.00 1.0%2.67 3.08 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 8.7 min QRUNON:0.292 cfs QPOST-DEV(BASIN):1.990 cfs QTOTAL:2.282 cfs Inlet Type:Combination QINTERCEPTED:1.410 cfs QBYPASS:0.872 cfs Gutter Spread Width:8.34 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin KB-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 10/15/2021 1 of 19 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 39,161 0.899 0.95 0.854 0.95 1.10 1.05 1.00 0.899 Totals 39,161 0.899 0.854 0.899 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft)(ft/ft)(ft/2)(min) Sheet Flow 27.00 3.2%n/a 5.42 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 631.00 1.6%2.74 3.84 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 9.3 min QRUNON:0.088 cfs QPOST-DEV(BASIN):2.318 cfs QTOTAL:2.406 cfs Inlet Type:Combination QINTERCEPTED:0.825 cfs QBYPASS:0.314 cfs Gutter Spread Width:5.04 ft Gutter Spread Width:4.08 ft (AUTODESK HYDRAFLOW) Buffalo Run | Post-Development Subbasin KB-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 10/15/2021 2 of 19 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 41,507 0.953 0.75 0.715 0.75 1.10 0.83 0.83 0.786 Totals 41,507 0.953 0.715 0.786 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 2.1%n/a 7.38 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 465.00 1.3%3.06 2.53 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 9.9 min QRUNON:0.547 cfs QPOST-DEV(BASIN):1.940 cfs QTOTAL:2.488 cfs Inlet Type:Combination QINTERCEPTED:1.489 cfs QBYPASS:0.998 cfs Gutter Spread Width:7.20 ft Depth of Flow in Gutter:3.2 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 10/15/2021 3 of 19 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 0.80 0.288 0.80 1.10 0.88 0.88 0.317 Totals 15,694 0.360 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 14.00 2.1%n/a 4.01 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 276.00 1.1%2.37 1.94 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 6.0 min QRUNON:0.000 cfs QPOST-DEV(BASIN):1.085 cfs QTOTAL:1.085 cfs Inlet Type:Combination QINTERCEPTED:0.793 cfs QBYPASS:0.292 cfs Gutter Spread Width:5.30 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 10/15/2021 4 of 19 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 0.80 0.269 0.80 1.10 0.88 0.88 0.295 Totals 14,621 0.336 0.269 0.295 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft)(ft/ft)(ft/2)(min) Sheet Flow 55.00 0.7%n/a 13.83 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 231.00 1.2%2.13 1.80 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 15.6 min QRUNON:0.000 cfs QPOST-DEV(BASIN):0.545 cfs QTOTAL:0.545 cfs Inlet Type:Combination QINTERCEPTED:0.457 cfs QBYPASS:0.088 cfs Gutter Spread Width:3.82 ft Depth of Flow in Gutter:2.0 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 10/15/2021 5 of 19 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 17.00 2.6%n/a 4.30 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 270.00 1.0%2.43 1.85 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 6.2 min QRUNON:0.000 cfs QPOST-DEV(BASIN):1.398 cfs QTOTAL:1.398 cfs Inlet Type:Combination QINTERCEPTED:0.967 cfs QBYPASS:0.430 cfs Gutter Spread Width:5.99 ft Depth of Flow in Gutter:2.7 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 10/15/2021 6 of 19 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 0.80 0.214 0.80 1.10 0.88 0.88 0.235 Totals 11,643 0.267 0.214 0.235 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 1.8%n/a 6.56 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 264.00 1.0%2.06 2.14 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 8.7 min QRUNON:0.000 cfs QPOST-DEV(BASIN):0.631 cfs QTOTAL:0.631 cfs Inlet Type:Combination QINTERCEPTED:0.514 cfs QBYPASS:0.117 cfs Gutter Spread Width:4.25 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 10/15/2021 7 of 19 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 27,498 0.631 0.95 0.600 0.95 1.10 1.05 1.00 0.631 Totals 27,498 0.631 0.600 0.631 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%2.93 0.51 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 5.0 min QRUNON:0.000 cfs QPOST-DEV(BASIN):2.415 cfs QTOTAL:2.415 cfs Inlet Type:Sag QINTERCEPTED:2.415 cfs QBYPASS:0.000 cfs Gutter Spread Width:11.70 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 10/15/2021 8 of 19 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 30,852 0.708 0.85 0.602 0.85 1.10 0.94 0.94 0.662 Totals 30,852 0.708 0.602 0.662 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):2.089 cfs QTOTAL:2.089 cfs Inlet Type:Sag QINTERCEPTED:2.089 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 10/15/2021 9 of 19 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 10/15/2021 10 of 19 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 69,082 1.586 0.80 1.269 0.80 1.10 0.88 0.88 1.396 Totals 69,082 1.586 1.269 1.396 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%3.65 0.00 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 7.6 min QRUNON:0.000 cfs QPOST-DEV(BASIN):4.089 cfs QTOTAL:4.089 cfs Inlet Type:Sag QINTERCEPTED:4.089 cfs QBYPASS:0.000 cfs Gutter Spread Width:22.27 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 10/15/2021 11 of 19 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 80,240 1.842 0.85 1.566 0.85 1.10 0.94 0.94 1.722 Totals 80,240 1.842 1.566 1.722 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%3.66 0.00 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 10.3 min QRUNON:0.000 cfs QPOST-DEV(BASIN):4.141 cfs QTOTAL:4.141 cfs Inlet Type:Sag QINTERCEPTED:4.141 cfs QBYPASS:0.000 cfs Gutter Spread Width:25.21 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 10/15/2021 12 of 19 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 97,067 2.228 0.80 1.783 0.80 1.10 0.88 0.88 1.961 Totals 97,067 2.228 1.783 1.961 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft)(ft/ft)(ft/2)(min) Sheet Flow 29.00 1.5%n/a 7.29 Shallow Concentrated Flow 340.00 1.6%2.63 2.15 Gutter 0.00 1.6%3.83 0.00 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 9.4 min QRUNON:0.000 cfs QPOST-DEV(BASIN):4.994 cfs QTOTAL:4.994 cfs Inlet Type:Sag QINTERCEPTED:4.994 cfs QBYPASS:0.000 cfs Gutter Spread Width:26.32 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 10/15/2021 13 of 19 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 10/15/2021 14 of 19 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 45,417 1.043 0.60 0.626 0.60 1.10 0.66 0.66 0.688 Totals 45,417 1.043 0.626 0.688 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 45,417 1.043 0.70 0.730 0.70 1.10 0.77 0.77 0.803 Totals 45,417 1.043 0.730 0.803 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):1.408 cfs QTOTAL:1.408 cfs POST-DEVELOPMENT FLOW RATES Buffalo Run | Post-Development Subbasin P-1 - Time of Concentration PRE-DEVELOPMENT FLOW RATE FOR DESIGN STORM 1.057 cfs N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 10/15/2021 15 of 19 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 4,107 0.094 0.80 0.075 0.80 1.10 0.88 0.88 0.083 Totals 4,107 0.094 0.075 0.083 FLOW PATH SUMMARY BY TYPE Flow Type Flow Length Average Land Slope Average Velocity Travel Time (ft)(ft/ft)(ft/2)(min) Sheet Flow 111.00 10.8%n/a 13.77 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 0.00 1.6%1.90 0.00 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 13.8 min QRUNON:0.000 cfs QPOST-DEV(BASIN):0.166 cfs QTOTAL:0.166 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 10/15/2021 16 of 19 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 2,818 0.065 0.80 0.052 0.80 1.10 0.88 0.88 0.057 Totals 2,818 0.065 0.052 0.057 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 3.5%n/a 4.78 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 0.00 1.2%1.83 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:0.042 cfs QPOST-DEV(BASIN):0.218 cfs QTOTAL:0.260 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 10/15/2021 17 of 19 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 2,781 0.064 0.80 0.051 0.80 1.10 0.88 0.88 0.056 Totals 2,781 0.064 0.051 0.056 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 3.5%n/a 4.78 Shallow Concentrated Flow 0.00 0.0%0.00 0.00 Gutter 0.00 1.2%2.05 0.00 Trapezoid/Triangular Channel 0.00 0.0%0.00 0.00 5.0 min QRUNON:0.269 cfs QPOST-DEV(BASIN):0.215 cfs QTOTAL:0.484 cfs Buffalo Run | Post-Development Subbasin X-2S - Time of Concentration POST-DEVELOPMENT FLOW RATES <= 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 10/15/2021 18 of 19 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 86,320 1.982 0.30 0.594 0.30 1.10 0.33 0.33 0.654 Totals 86,320 1.982 0.594 0.654 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 324.00 1.6%1.73 6.0 28.0 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 Grass/Paved Areas 86,320 1.982 0.23 0.456 0.23 1.10 0.25 0.25 0.501 Totals 86,320 1.982 0.456 0.501 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 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):0.446 cfs QTOTAL:0.446 cfs Buffalo Run | Post-Development Subbasin PARK - Time of Concentration POST-DEVELOPMENT FLOW RATES PRE-DEVELOPMENT FLOW RATE FOR DESIGN STORM 0.831 cfs N:\6475\005 - Buffalo Run - Site Plan\04 Design\Calcs\Storm\6475_StormwaterCalcs_CityofBozeman_25yr.xlsm 10/15/2021 19 of 19 Inlet Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Friday, Oct 15 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) = 0.48 Highlighted Q Total (cfs) = 0.48 Q Capt (cfs) = 0.48 Q Bypass (cfs) = -0- Depth at Inlet (in) = 1.64 Efficiency (%) = 100 Gutter Spread (ft) = 2.90 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 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) = 0.79 Highlighted Q Total (cfs) = 0.79 Q Capt (cfs) = 0.79 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.06 Efficiency (%) = 100 Gutter Spread (ft) = 4.08 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 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) = 0.65 Highlighted Q Total (cfs) = 0.65 Q Capt (cfs) = 0.65 Q Bypass (cfs) = -0- Depth at Inlet (in) = 1.88 Efficiency (%) = 100 Gutter Spread (ft) = 3.57 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 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) = 1.04 Highlighted Q Total (cfs) = 1.04 Q Capt (cfs) = 1.04 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.36 Efficiency (%) = 100 Gutter Spread (ft) = 4.91 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 KB-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) = 2.28 Highlighted Q Total (cfs) = 2.28 Q Capt (cfs) = 2.28 Q Bypass (cfs) = -0- Depth at Inlet (in) = 3.59 Efficiency (%) = 100 Gutter Spread (ft) = 8.34 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 KB-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) = 0.79 Highlighted Q Total (cfs) = 0.79 Q Capt (cfs) = 0.79 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.06 Efficiency (%) = 100 Gutter Spread (ft) = 4.08 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-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) = 2.42 Highlighted Q Total (cfs) = 2.42 Q Capt (cfs) = 2.42 Q Bypass (cfs) = -0- Depth at Inlet (in) = 2.97 Efficiency (%) = 100 Gutter Spread (ft) = 11.70 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-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. Friday, Oct 15 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) = 4.08 Highlighted Q Total (cfs) = 4.08 Q Capt (cfs) = 4.08 Q Bypass (cfs) = -0- Depth at Inlet (in) = 3.38 Efficiency (%) = 100 Gutter Spread (ft) = 22.27 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-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) = 4.15 Highlighted Q Total (cfs) = 4.15 Q Capt (cfs) = 4.15 Q Bypass (cfs) = -0- Depth at Inlet (in) = 3.41 Efficiency (%) = 100 Gutter Spread (ft) = 25.21 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-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) = 5.01 Highlighted Q Total (cfs) = 5.01 Q Capt (cfs) = 5.01 Q Bypass (cfs) = -0- Depth at Inlet (in) = 3.35 Efficiency (%) = 100 Gutter Spread (ft) = 27.82 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- 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.doc 1 of 3 The Homestead at Buffalo Run Storm Water Maintenance Plan October 2021 The Homestead at Buffalo Run (Buffalo Run) has a site-wide storm drainage system that is being constructed to treat, store and convey 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 primarily through underground detention and treatment basins. The Buffalo Run storm drain system is owned and operated by Bridger Development Strategies, LLC (BDS) and includes all storm drain and surface water treatment and conveyance facilities within the private property, including interior parking facilities. It does not include the following systems around the site perimeter, which will be operated and maintained by City of Bozeman and for which easements will be provided for access and maintenance by the City: • Facility R-1 o Fowler Lane o Kurk Drive (west of Avenue B) o Northwest portion of Avenue B • Facility R-2 o Portion of Kurk Drive (west of midblock crossing) o Northeast portion of Avenue B • Facility R-3 o North portion of Avenue C (north of midblock crossing) o East 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 Avenue B (south of midblock crossing) Bridger Development Strategies, LLC (BDS) shall maintain their components of the storm drainage system in accordance with this maintenance plan and with the applicable City of Bozeman regulations. BDS will maintain a written account of all maintenance and repair activities, such as a log book, 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. n:\6475\005 - buffalo run - site plan\04 design\reports\stormreport\appendices\app-d_o&mmanual\6475.005_o&mplan.doc 2 of 3 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. 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, n:\6475\005 - buffalo run - site plan\04 design\reports\stormreport\appendices\app-d_o&mmanual\6475.005_o&mplan.doc 3 of 3 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. 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.