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Home My WebLink About18 - Design Report - Icon Apartments at Ferguson Farm - Stormwater STORM DRAINAGE PLAN For Icon Apartment Homes at Ferguson Farm Bozeman, Montana prepared for: Braxton & Klein Capital Partners, LLC PO Box 11890 Bozeman, Montana prepared by: Sanderson Stewart 106 E. Babcock Bozeman, MT 59715 October 2018 July 25, 2017 Updated October, 03 2018 Project No. 17007.02 STORM DRAINAGE PLAN FOR ICON APARTMENT HOMES AT FERGUSON FARM BOZEMAN, MONTANA OVERVIEW NARRATIVE The purpose of this drainage plan is to quantify storm drainage improvements required for the proposed Icon Apartment Homes at Ferguson Farm at 4605 West Babcock Road in Bozeman, Montana. The site is located south of W. Babcock Street, west of Resort Drive, north of Fallon Street and east of South Cottonwood Road. The approximately 20-acre lot will include 18 apartment buildings, one clubhouse and pool and one maintenance building with a dog washing station. The 18 apartment buildings include a total of 336 units made up of one, two and three bedroom apartments. Site improvements for the buildings will include drive aisles, sidewalks, parking lots and open space. Two public easement access roads, Stafford Avenue and Palisade Drive, and one public city park will be constructed as part of the proposed apartment community project. Generally, the stormwater runoff within the apartment complex will be mitigated using pervious pavers, manufactured ADS chamber systems and dry wells. The pervious pavers will treat the water quality (the first 0.5-inch of runoff) and the water quantity volume (25-year storm event for all durations). All infiltration systems for the apartment complex have been designed to infiltrate and retain the 25-year storm event. The site currently retains 6,037 CF in an existing detention pond near the southwest corner of the site. The 6,037 CF is the cumulative volume of the runoff from the northern side of Fallon’s roadway crown and the deficient runoff from the Ferguson Farm subdivision from the south. Fallon Street, North of the roadway crown = 10-year, 2-hour runoff volume = 1,350 CF Ferguson Farm’s Deficient volume = 4,687 CF Total Runoff Volume = 6,037 CF V:17007_02_Storm_Drainage_Plan_030716_SC 2 (04/09/18) SN/jil This deficient runoff will be retained in an ADS chamber system (Chamber E) near the southwest corner of the site that is detached from the Icon Apartment Homes stormwater system. And the runoff from Fallon Street will be in Chamber A located at the northeast corner of the Stafford Avenue and Palisades Drive intersection. A portion at the eastern end of Palisade Drive will drain into Resort Drive to an inlet located approximately 130 feet north of the intersection of Palisade Drive and Resort drive. The total watershed area to this inlet, included the area from Palisade Drive is 0.371 acres and has a peak flow of 1.41 cfs from the 25-year design storm. This inlet is a sag inlet and an inflow rate of 1.41 cfs would result in a spread width of 2.12 feet which is less than the length of 3.5 foot concrete apron. Therefore, this inlet has the capacity to handle the increased runoff from Palisade Drive. The appendices include the runoff and inlet capacity calculations. Runoff from Fallon Street and the portion of Stafford Avenue south of Palisade Drive and Palisade Drive west of the crosswalk and south of the center roadway crown will be captured in storm drain inlets and conveyed into an underground ADS chamber system (Chamber A) located at the northeast corner of the Stafford Avenue and Palisade Drive intersection. Runoff from a portion of Stafford Avenue north of Palisade Drive and Palisade Drive west of the crosswalk and north of the center roadway crown is captured in inlets and conveyed to a chamber system (Chamber F) in the southwest corner of the intersection of Stafford Avenue and West Babcock Street. Runoff from the east portion Palisade Drive will be captured in storm drain inlets and retained in an underground ADS chamber system (Chamber C) adjacent to Palisade Drive. Runoff from the northern portion of Resort Drive will be captured and retained in an underground ADS chamber system (Chamber D). The southern portion Resort Drive is captured in an existing inlet and conveyed to the development to the east. There is not an increase in impervious cover or runoff to this existing inlet. The stormwater system is designed to convey and infiltrate the peak flows from the 25-year storm event. This is done in order to meet both the water quality and conveyance storm events described in The City of Bozeman Design Standards and Specifications Policy, dated March 2004. In the scenario where the area receives a larger storm event, the site has been designed to allow for large flows to spill over into the adjacent roadways. This report presents a summary of calculations performed to quantify the stormwater runoff for the improved site. All design criteria and calculations are in accordance with The City of Bozeman Design Standards and Specifications Policy, dated March 2004. The site stormwater improvements have been designed with the intent to meet the current City of Bozeman drainage regulations for the entire site to the extent feasible. Specific site information and criteria are described below: I. Project Information A. Address: The physical address for the site is 4605 West Babcock St, Bozeman, MT 59718 B. Legal Description: The site is located on Lot 3A of Minor Subdivision 365 V:17007_02_Storm_Drainage_Plan_030716_SC 3 (04/09/18) SN/jil C. Total Area: The area of the site is approximately 19.87 acres including public access easement area. Street Easement: 2.70 acres Park Easement: 1.61 acres Apartment Community: 15.56 acres D. Existing Impervious Area: Impervious Area – 0.00 acres Pervious Area – 19.87 acres E. Post-Development Impervious Area: As a result of the development, the site will exhibit the following qualities: Impervious Area – 14.27 acres Pervious Area – 5.60 acres F. Type of Development: The development will be high density apartment homes. II. Storm Drain Design Methodology Due to the large and compartmentalized site, 41 watersheds were delineated with individual discharge locations in order to quantify the required detention volume and peak runoff volumes. The individual watershed delineations are provided in a watershed figure in Appendix A. Discharge locations are either ADS chamber systems, pervious pavers or dry wells, and referred to as stormwater units for the remainder of the report. Individual calculation spreadsheets for each watershed and stormwater unit combination is provided in Appendix B, which calculates the required retention volume after infiltration and peak runoff rate. Also in Appendix B is Table 1 which summarizes the inputs and results from each watershed. The spreadsheets use the surface area calculations from the watershed delineations to calculate the runoff coefficient and adjusted runoff coefficient based on a frequency factor of 1.1. The adjusted runoff coefficient, area, intensity and rainfall duration is used to determine the runoff volume. The discharge volume is calculated from the storm duration and the discharge rate. A discharge rate for each stormwater unit was calculated to help determine the required detention volume. The discharge rate is a function of the infiltration rate and square footage of the stormwater unit, it calculates the rate that runoff exits the stormwater unit into the natural gravels. ℎ × ℎ∗× ℎ× 112 × 1 ℎ60 × 1 60 = ℎ The natural gravels are located 3-feet below the existing surface and have high infiltration rates and will be discussed in more detail later in this report. Tying the stormwater units into the natural gravels allows the stormwater to infiltrate into the soils and restores the natural hydrology of the site. It also allows for the detention volume to be reduced. The detention V:17007_02_Storm_Drainage_Plan_030716_SC 4 (04/09/18) SN/jil volume is the difference between the runoff volume to the stormwater unit and the discharge volume from the stormwater unit via infiltration. In many cases, the stormwater units are infiltrating runoff quicker than runoff flow rate to the stormwater unit. A detention volume is calculated when the stormwater unit cannot infiltrate at the rate of the incoming flow rate. The size of the stormwater unit was determined through an iterative process. The length and width of the stormwater unit was adjusted until the provided detention volume was greater than the required detention volume. That length and width was then used to design the stormwater system. A. Runoff Calculations: The modified rational method was used to determine peak runoff rates and volumes. It was assumed the rainfall is uniformly distributed over the area for the entire duration of the storm. The rational formula provided in The City of Bozeman Standard Specifications and Policy was used to calculate the peak runoff rates on site. The rainfall intensity for the site was calculated in part by using Figure I-2 and I-3. The peak runoff rate occurs when the duration of the storm equals the time of concentration. The provided time of concentration tools, Table I-2, Table I-3 and Figure I-1, in The City of Bozeman’s Design Standard and Specifications Policy were used to calculate the time of concentration for each of the major watersheds. However, since most watersheds are predominately impervious cover, all watersheds used a conservative time of concentration of 1-minute. The time of concentration was only relevant to the traditional (inlet and piping) stormwater infrastructure systems since the pervious paver systems meet the requirements for each rainfall duration. The runoff coefficient for a particular watershed is constant for a similar land use. The runoff coefficients provided in Table I-1 were used in calculating the peak runoff rates. B. Infiltration Rates: Five test pits were excavated in May of 2017. Groundwater was present at 6-feet below existing ground surface and native gravels were present at 3-feet below ground surface. It is assumed that seasonal high ground water is located at 6-feet below existing ground surface since the test pits were excavated during the typical seasonal high ground water season. It is also important to note that detention storage within the paver systems, chamber systems and drywells is only accounted for in the first 3 feet, 5 feet and 5 feet below existing ground surface elevation, respectively. Therefore, no required detention volume is accounted for below season high ground water. A geotechnical report has also been completed for the project in August 2017 and groundwater was generally found at 6-feet below the existing surface. At one boring, located at the very southwest corner of the site one boring showed groundwater at 2.2-feet deep. Besides the 2.2- foot deep water level at one boring, the next highest groundwater level was at 5.8 feet deep. A falling head infiltration test was completed at three of the five test pits and the average infiltration rate was found to be 160 inches/hour. The data of the tests is included in Appendix E. The design of the stormwater unit used an infiltration rate of 80 inches/hour to provide a factor of safety of two. V:17007_02_Storm_Drainage_Plan_030716_SC 5 (04/09/18) SN/jil C. Stormwater Unit Volumes Paver System: 1 square foot of pave drain = 1 cubic foot of storage. The project is proposing to use a 3-ft pervious paver section. The section, as shown on sheet C9.1, is made up of 6-inch as paver, and 30 inches as stone base. Native gravels are located at 3-feet below existing ground surface. This paver section was designed to ensure that the pavers are tied into native gravels. As shown in Appendix C, the ACF environmental storage capacity determination of PaveDrain spreadsheet shows that the proposed section of pave drain has the capacity to hold 1 cubic of runoff per 1 square foot of pave drain section. In most cases, the paver units were oversized in order to allow for the use of the mechanical installer because cost of the additional pavers is less than the cost to hand install the smaller paver units. The infiltration rate considered the entire area of the pervious paver unit. "# $% = "# &ℎ ×"# ℎ ’ 1 () 1) Chamber System: The online ADS StormTech Design Tool was used to calculate the detention volume in conjunction with the Appendix C spreadsheets to calculate the volume after infiltration. A general detail of the ADS StormTech Chamber system is provided on sheet C9.0. A trial and error method was used between the Appendix B spreadsheets and the ADS StormTech Design Tool to ensure that the length and width between the spreadsheet and the design tool match and that the provided volume from the design tool was larger than the required volume from the spreadsheet. The infiltration rate leaving the ADS system used the entire area of the chamber system. Dry Well: The detention volumes of dry wells were calculated by using the radius and depth of the dry well barrel. *+ $% = ,× -×*.ℎ The dry well barrels proposed have a 15-inch radius and are 5-feet in depth. The infiltration rate leaving the dry well system was assumed to be the surface area of the bottom of the barrel. Most of the dry wells are located in shallow depressions. The storage provided in the depressions is included in the storage capacity calculations for the dry wells. The volume calculations for the depression areas are provided in Appendix C. D. Water Quality The development project is greater than one acre and therefore will infiltrate runoff generated from the first 0.5-inches of rainfall from a 24-hour storm. Table 1 and Figure 1 in Appendix A, show the locations of the watersheds on site. Table 1 shows the required storage volume V:17007_02_Storm_Drainage_Plan_030716_SC 6 (04/09/18) SN/jil for each watershed calculated. The runoff calculations are in Appendix B. Table 2 outlines the provided storage and type of stormwater unit for each watershed. Each stormwater unit retains the 25-year storm and infiltrates the 25-year runoff volume in under 72 hours. The stormwater storage facilities are designed to remove pollutants such as solids, silts, oils, and greases. There is no oil/water separator required on site. The media below the pavers and chambers will filter any solids, silts, oils and greases. All inlets and manholes are designed in accordance with the City of Bozeman standard details. However, a larger 18-inch sump has been design in the manholes upstream of the ADS chamber systems. Alignment between manholes is straight. However, there are limited manholes onsite due to the use of pervious paver. Storm sewer systems are designed with a slope and pipe diameter as to ensure a velocity of 3-fps. The storm sewers within the public access easement are public and will be maintained by the City of Bozeman. A minimum pipe size of 12-inch for inlet structures and 15-inch for all other structures has been used for design. E. Outlet Structures There are no offsite discharge locations as part of this project. As previously mentioned, the runoff from the southern portion of Resort Drive (Watershed 6) is captured in an existing inlet which discharges off site. Since the impervious cover draining to this inlet is not increasing, the inlet was left as is. The stormwater management plan on site is designed to infiltrate the 25-year storm event. The ultimate destination of the stormwater runoff within the apartment community is the groundwater table. III. Stormwater Design A. Pavers: Pervious pavers were proposed within the parking lot areas of the apartment complex. Specifically, the pavers are located within the first couple of feet at the beginning of the parking stalls. The area surrounding the pavers are graded towards the pavers to allow runoff to sheet flow and infiltrate into the paver section. The pavers have a flat cross slope but have a slight longitudinal grade. Since the infiltration rate is so high, pavers did not have to cover the entire parking area, only small sections were needed. The parking stalls were chosen as a desirable area for pavers because they would be susceptible to lower traffic speeds. It also seemed more practical to divert flow to parking areas rather than drive aisle. Additionally, the pervious pavers needed to remain 30 feet away and have at least 18-inches of vertical separation for perpendicular crossings from all water mains in order to meet DEQ regulations. This, in many cases, limited the potential paver areas to the parking stalls. In areas where the pavers are within 20-feet of a building or public street, the paver section will have an impermeable fabric layer down to a depth of 4-feet on the side of the paver section that is adjacent V:17007_02_Storm_Drainage_Plan_030716_SC 7 (04/09/18) SN/jil to the building or public street. The intent of the impermeable fabric layer is to protect the building foundations from saturated soils. In the event of a storm larger than the 50-year event, the site has been graded to allow for any excess flow to overtop into the adjacent public roadways to reduce the potential for flooding at the buildings. The paver section shown on Sheet C8.2 shows 1”-3/4” clean angular stone tying into native gravels at a 3’-4’ depth. However, the 8-inch leveling layer of sand also ties into native graves at 8-inches below the native gravel elevation. The leveling sand and gravels both tie into the native gravels. The limiting infiltration rate is the infiltration rate of the native gravels which the paver system ties into. The limiting infiltration rate was found to be 80 inches/hour as described above and it was used as the design infiltration rate. B. Chambers: Four out of the six chamber systems are designed to retain the 25-year runoff volume from the new and existing public roads (Chamber A, C1, C2, D, F). One chamber system, Chamber E, is used to retain runoff from the deficient volume from the Ferguson Farms subdivision south of Fallon Street. The other chamber system, Chamber B, is used to retain runoff from the pool area. In areas where the chambers are within 20-feet of a building or public street, the chamber section will have an impermeable fabric layer down to a depth of 4-feet on the side of the chamber section that is adjacent to the building or public street. The chamber bedding will tie into the native gravels in order to promote infiltration. Chamber system A is designed to retain the runoff from Fallon Drive, the portion of Stafford Avenue south of Palisades Drive and a portion Palisades Drive west of the crosswalk. The chamber system is located within the pervious area adjacent to Building 17. The system is accessible for maintenance by Palisade Drive or the parking lot south of Building 17. The chamber system will not be deeper than 5-feet below the existing ground surface and does not account for volume below 5-feet. Chamber system B is located within the pervious area southwest of the pool area. Chamber system B is design to retain runoff from the pool patio, sidewalk and landscaped area. Chamber system B is accessible for maintenance from the parking area to the west. The chamber system is located here in order to comply with landscape requirements and water easement regulations. The chamber system will not be deeper than 5-feet below the existing ground surface and does not account for volume below 5-feet. Chamber system C1 and C2 are located within the boulevard area of Palisade Drive. The chamber systems will retain runoff from the portion of Palisades Drive east of the crosswalk. The Chamber systems are located in an area that is easily accessible for maintenance purposes. The chamber system will not be deeper than 5-feet below the existing ground surface and does not account for volume below 5-feet. Chamber system D is located at the northeast corner of the site and is used to retain runoff from a portion of Resort Drive. The chamber system is accessible for maintenance from Resort Drive and the parking lot east of Building 13. The chamber V:17007_02_Storm_Drainage_Plan_030716_SC 8 (04/09/18) SN/jil system will not be deeper than 5-feet below the existing ground surface and does not account for volume below 5-feet. Chamber system E is located at the southwest corner of the site and is used to retain the deficient volume from the Ferguson Farms subdivision to the south. The system will consist of a single row of chambers. The chamber system will not be deeper than 5-feet below the existing ground surface and does not account for volume below 5- feet. The chamber system is accessible for maintenance from Stafford Avenue. Like the other Chamber Systems, infiltration of the runoff volume was included in the required storage volume calculations. Chamber system F is located at the northwest corner of the site and retains the volume from a portion of Stafford Avenue north of its intersection with Palisade Drive. The chamber system is accessible for maintenance from Stafford Avenue. The chamber system will not be deeper than 5-feet below the existing ground surface and does not account for volume below 5-feet. In the event of a storm larger than the 50-year event, the site has been graded to allow for any excess flow to overtop into the adjacent public roadways to reduce the potential for flooding at the buildings. C. Dry Wells: The drywells on site are designed to retain runoff from sidewalk and landscape area. The flows to the drywells are relatively small compared to the other flows on site do to the large amount of pervious area in their watersheds. Flow to the dry well will sheet flow over grassed area, which will slow down peak flows and provide some pretreatment as filtration. In the event of a storm larger than the 50-year event, the site has been graded to allow for any excess flow to overtop into the adjacent public roadways to reduce the potential for flooding at the buildings. V:17007_02_Storm_Drainage_Plan_030716_SC 9 (04/09/18) SN/jil Appendix A WATERSHED MAP V:17007_02_Storm_Drainage_Plan_030716_SC 10 (04/09/18) SN/jil Appendix B HYDROLOGY CALCULATIONS Table 1: Watershed Properties Watershed SW Unit # Total Area (SF) Impervious Area (SF) Pervious Area (SF) 25-year Runoff Volume After Infiltration (CF)Provided Storage (CF) 1 Unit 1 27535 20625 6910 1577.01 1814.00 2 Unit 1 25809 20969 4840 3 Unit 2 13165 7564 5601 373.66 571.10 4 Unit 3 10721 5471 5250 185.23 320.40 5 Unit 4 14287 7631 6656 394.40 635.10 6 Offsite 34525 27699 6826 5853.82 N/A 7 Unit 5 30217 23129 7088 392.81 403.17 8 Unit 6 10781 10715 66 103.48 427.20 9 Unit 7 28062 24752 3310 409.36 409.40 10 Unit 8 14374 12570 1804 207.83 209.15 11 Unit 9 7196 6910 286 154.50 213.60 12 Unit 10 51919 29513 22406 557.60 606.00 13 Drain 5188 5188 0 1039.49 #N/A 14 Unit 11 12804 7336 5468 357.22 402.12 15 Unit 12 10173 10016 157 154.50 172.55 16 Unit 13 25059 19677 5382 329.20 344.96 17 Unit 14 17267 16355 912 188.66 427.20 18 Unit 1 34625 26288 8337 19 Unit 16 4825 4820 5 39.35 249.20 20 Unit 17 20512 19013 1499 223.86 471.70 21 Unit 18 27598 27598 0 230.02 1388.40 22 Unit 19 63397 49197 14200 571.26 1553.05 23 Unit 20A 19238 13403 5835 227.93 308.00 24 Unit 1 27576 19950 7626 25 Unit 15 6820 2746 4074 1206.36 1350.00 26 Unit 15 12464 9650 2814 27 Unit 20B 8647 6039 2608 94.89 153.00 28 Unit 22 63920 21205 42715 29 Unit 21 23767 13603 10164 242.69 318.00 30 Unit 22 59707 53228 6479 1207.55 1633.15 31 Unit 23 9694 9307 387 83.95 427.20 32 Unit 15 29542 19415 10127 33 Unit 24 25936 14315 11621 185.30 493.95 34 Unit 26 12044 9803 2241 323.72 319.19 35 Unit 28 15733 15733 0 157.72 578.50 36 Unit 29 66946 63080 3866 904.15 1223.75 37 Unit 27 8196 6891 1305 76.62 226.95 38 Unit 30 3972 3567 405 30.12 186.90 39 Unit 15 17229 7088 10141 40 Unit 25 - Future 27382 13184 14198 991.35 Future 41 Unit 25 - Future 31854 31854 0 153.67 481.00 Included in WS 25 Calculations Included in WS 25 Calculations Included in WS 40 Calculations Ferguson Farms Deficent Volume Included in WS 1 Calculations Included in WS 1 Calculations Included in WS 1 Calculations Included in WS 25 Calculations Included in WS 30 Calculations Table 2: Stormwater Unit Properties Watershed SW Unit # Type Width (FT) Length (FT) Depth (FT) *Storage (CF) 1 & 2 & 18 & 24 Unit 1 Chamber A 1814.00 3 Unit 2 Dry Well 28.27 4 571.10 4 Unit 3 PaveDrain 6 60 320.40 5 Unit 4 Dry Well 28.27 4 635.10 6 Offiste 7 Unit 5 PaveDrain 6 75.5 403.17 8 Unit 6 PaveDrain 5 96 427.20 9 Unit 7 PaveDrain 5 92 409.40 10 Unit 8 PaveDrain 10 23.5 209.15 11 Unit 9 PaveDrain 10 24 213.60 12 Unit 10 Chamber B 606.00 13 Drain to Sewer 14 Unit 11 Dry Well 100.53 4 402.12 15 Unit 12 PaveDrain 4 48.47 172.55 16 Unit 13 PaveDrain 8 48.45 344.96 17 Unit 14 PaveDrain 5 96 427.20 19 Unit 16 PaveDrain 5 56 249.20 20 Unit 17 PaveDrain 5 106 471.70 21 Unit 18 PaveDrain 5 312 1388.40 22 Unit 19 PaveDrain 5 349 1553.05 23 Unit 20A Chamber C1 308.00 27 Unit 20B Chamber C2 153.00 25 & 26 & 32 & 39 Unit 15 Chamber F 1350.00 29 Unit 21 Chamber D 318.00 30&28 Unit 22 PaveDrain 5 367 1633.15 31 Unit 23 PaveDrain 5 96 427.20 33 Unit 24 PaveDrain 5 111 493.95 34 Unit 26 Dry Well 56.55 4 319.19 35 Unit 28 PaveDrain 5 130 578.50 36 Unit 29 PaveDrain 5 275 1223.75 37 Unit 27 PaveDrain 5 51 226.95 38 Unit 30 PaveDrain 5 42 186.90 40&41 Future Chambers Ferguson Farms Chamber E Chamber E 481.00 See Appendix C See Appendix C See Appendix C See Appendix C See Appendix C See Appendix C See Appendix C Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =2.92 cfs 21 75 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 87832 2.016 0.9 1.1 0.99 0.99 1.996181818 27713 0.636 0.2 1.1 0.22 0.22 0.139964646 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 115545 2.6525 2.1361 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =2.14 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 10.72 22.90 5 3.83 8.17 10 2.46 5.24 15 1.89 4.05 20 1.58 3.37 25 1.37 2.92 30 1.22 2.60 35 1.10 2.35 40 1.01 2.16 45 0.94 2.00 50 0.88 1.87 55 0.82 1.76 60 0.78 1.67 75 0.68 1.44 90 0.60 1.29 105 0.55 1.16 120 0.50 1.07 150 0.43 0.93 180 0.39 0.82 360 0.25 0.53 720 0.16 0.34 1440 0.10 1,577.01 ft3 22.90 (ft3/s) 14673.49 126000.00 ----- 18832.34 252000.00 ----- 8908.24 31500.00 ----- 11433.06 63000.00 ----- 7698.37 21000.00 ----- 8342.31 26250.00 ----- 6940.98 15750.00 ----- 7337.06 18375.00 ----- 5998.30 10500.00 ----- 6500.04 13125.00 ----- 5617.24 8750.00 ----- 5813.32 9625.00 ----- 5183.65 7000.00 ----- 5408.17 7875.00 ----- 4673.66 5250.00 ----- 4940.36 6125.00 ----- 4038.91 3500.00 538.91 4376.75 4375.00 1.75 3146.98 1750.00 1396.98 3641.55 2625.00 1016.55 1373.71 175.00 1198.71 2452.01 875.00 1577.01 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.7321 Cwd x Cf =0.81 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 1, 2, 18, 24 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Area (sq.ft.)Infiltration Rate (in/hr) Discharge Rate, d =0.05 cfs 28.27 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 7564 0.174 0.9 1.1 0.99 0.99 0.171909091 5601 0.129 0.2 1.1 0.22 0.22 0.028287879 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 13165 0.3022 0.2002 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.20 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 2.15 5 3.83 0.77 10 2.46 0.49 15 1.89 0.38 20 1.58 0.32 25 1.37 0.27 30 1.22 0.24 35 1.10 0.22 40 1.01 0.20 45 0.94 0.19 50 0.88 0.18 55 0.82 0.17 60 0.78 0.16 75 0.68 0.14 90 0.60 0.12 105 0.55 0.11 120 0.50 0.10 150 0.43 0.09 180 0.39 0.08 360 0.25 0.05 720 0.16 0.03 1440 0.10 373.66 ft3 2.15 (ft3/s) 1375.18 2261.95 ----- 1764.94 4523.89 ----- 834.87 565.49 269.38 1071.49 1130.97 ----- 721.48 376.99 344.49 781.83 471.24 310.59 650.50 282.74 367.76 687.62 329.87 357.75 562.15 188.50 373.66 609.18 235.62 373.56 526.44 157.08 369.36 544.82 172.79 372.03 485.80 125.66 360.14 506.85 141.37 365.48 438.01 94.25 343.76 463.00 109.96 353.05 378.52 62.83 315.69 410.18 78.54 331.64 294.93 31.42 263.51 341.28 47.12 294.16 128.74 3.14 125.60 229.80 15.71 214.09 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.6022 Cwd x Cf =0.66 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 3 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.67 cfs 6 60 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 5471 0.126 0.9 1.1 0.99 0.99 0.124340909 5250 0.121 0.2 1.1 0.22 0.22 0.026515152 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 10721 0.2461 0.1509 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.15 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 1.62 5 3.83 0.58 10 2.46 0.37 15 1.89 0.29 20 1.58 0.24 25 1.37 0.21 30 1.22 0.18 35 1.10 0.17 40 1.01 0.15 45 0.94 0.14 50 0.88 0.13 55 0.82 0.12 60 0.78 0.12 75 0.68 0.10 90 0.60 0.09 105 0.55 0.08 120 0.50 0.08 150 0.43 0.07 180 0.39 0.06 360 0.25 0.04 720 0.16 0.02 1440 0.10 57.01 ft3 1.62 (ft3/s) 1036.25 28800.00 ----- 1329.95 57600.00 ----- 629.11 7200.00 ----- 807.41 14400.00 ----- 543.66 4800.00 ----- 589.14 6000.00 ----- 490.18 3600.00 ----- 518.15 4200.00 ----- 423.60 2400.00 ----- 459.04 3000.00 ----- 396.69 2000.00 ----- 410.54 2200.00 ----- 366.07 1600.00 ----- 381.93 1800.00 ----- 330.06 1200.00 ----- 348.89 1400.00 ----- 285.23 800.00 ----- 309.09 1000.00 ----- 222.24 400.00 ----- 257.17 600.00 ----- 97.01 40.00 57.01 173.16 200.00 ----- = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.5572 Cwd x Cf =0.61 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 4 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Area (sq.ft.)Infiltration Rate (in/hr) Discharge Rate, d =0.05 cfs 28.27 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 7631 0.175 0.9 1.1 0.99 0.99 0.173431818 6656 0.153 0.2 1.1 0.22 0.22 0.033616162 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 14287 0.3280 0.2070 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.21 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 2.22 5 3.83 0.79 10 2.46 0.51 15 1.89 0.39 20 1.58 0.33 25 1.37 0.28 30 1.22 0.25 35 1.10 0.23 40 1.01 0.21 45 0.94 0.19 50 0.88 0.18 55 0.82 0.17 60 0.78 0.16 75 0.68 0.14 90 0.60 0.12 105 0.55 0.11 120 0.50 0.10 150 0.43 0.09 180 0.39 0.08 360 0.25 0.05 720 0.16 0.03 1440 0.10 394.40 ft3 2.22 (ft3/s) 1422.24 2261.95 ----- 1825.34 4523.89 ----- 863.44 565.49 297.95 1108.16 1130.97 ----- 746.17 376.99 369.18 808.59 471.24 337.35 672.76 282.74 390.02 711.15 329.87 381.28 581.39 188.50 392.90 630.02 235.62 394.40 544.46 157.08 387.38 563.46 172.79 390.67 502.43 125.66 376.77 524.19 141.37 382.82 453.00 94.25 358.75 478.85 109.96 368.89 391.48 62.83 328.64 424.22 78.54 345.68 305.02 31.42 273.61 352.96 47.12 305.84 133.15 3.14 130.01 237.66 15.71 221.96 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.5739 Cwd x Cf =0.63 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 5 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Discharge Rate, d =0.00 cfs Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 27699 0.636 0.9 1.1 0.99 0.99 0.629522727 6826 0.157 0.2 1.1 0.22 0.22 0.034474747 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 34525 0.7926 0.6640 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.66 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 10.72 7.12 5 3.83 2.54 10 2.46 1.63 15 1.89 1.26 20 1.58 1.05 25 1.37 0.91 30 1.22 0.81 35 1.10 0.73 40 1.01 0.67 45 0.94 0.62 50 0.88 0.58 55 0.82 0.55 60 0.78 0.52 75 0.68 0.45 90 0.60 0.40 105 0.55 0.36 120 0.50 0.33 150 0.43 0.29 180 0.39 0.26 360 0.25 0.16 720 0.16 0.11 1440 0.10 5,853.82 ft3 7.12 (ft3/s) 4561.09 0.00 4561.09 5853.82 0.00 5853.82 2769.03 0.00 2769.03 3553.84 0.00 3553.84 2392.95 0.00 2392.95 2593.12 0.00 2593.12 2157.53 0.00 2157.53 2280.64 0.00 2280.64 1864.50 0.00 1864.50 2020.46 0.00 2020.46 1746.06 0.00 1746.06 1807.01 0.00 1807.01 1611.28 0.00 1611.28 1681.07 0.00 1681.07 1452.76 0.00 1452.76 1535.65 0.00 1535.65 1255.45 0.00 1255.45 1360.47 0.00 1360.47 978.20 0.00 978.20 1131.94 0.00 1131.94 427.00 0.00 427.00 762.18 0.00 762.18 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.7616 Cwd x Cf =0.84 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 6 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.84 cfs 6 75.5 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 23129 0.531 0.9 1.1 0.99 0.99 0.525659091 7088 0.163 0.2 1.1 0.22 0.22 0.03579798 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 30217 0.6937 0.5615 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.56 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 6.02 5 3.83 2.15 10 2.46 1.38 15 1.89 1.06 20 1.58 0.88 25 1.37 0.77 30 1.22 0.68 35 1.10 0.62 40 1.01 0.57 45 0.94 0.53 50 0.88 0.49 55 0.82 0.46 60 0.78 0.44 75 0.68 0.38 90 0.60 0.34 105 0.55 0.31 120 0.50 0.28 150 0.43 0.24 180 0.39 0.22 360 0.25 0.14 720 0.16 0.09 1440 0.10 392.81 ft3 6.02 (ft3/s) 3856.73 36240.00 ----- 4949.82 72480.00 ----- 2341.41 9060.00 ----- 3005.03 18120.00 ----- 2023.41 6040.00 ----- 2192.66 7550.00 ----- 1824.34 4530.00 ----- 1928.45 5285.00 ----- 1576.57 3020.00 ----- 1708.45 3775.00 ----- 1476.41 2516.67 ----- 1527.95 2768.33 ----- 1362.45 2013.33 ----- 1421.46 2265.00 ----- 1228.41 1510.00 ----- 1298.51 1761.67 ----- 1061.57 1006.67 54.91 1150.37 1258.33 ----- 827.14 503.33 323.81 957.13 755.00 202.13 361.06 50.33 310.73 644.48 251.67 392.81 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.7358 Cwd x Cf =0.81 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 7 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.89 cfs 5 96 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 10715 0.246 0.9 1.1 0.99 0.99 0.243522727 66 0.002 0.2 1.1 0.22 0.22 0.000333333 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 10781 0.2475 0.2439 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.24 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 2.61 5 3.83 0.93 10 2.46 0.60 15 1.89 0.46 20 1.58 0.38 25 1.37 0.33 30 1.22 0.30 35 1.10 0.27 40 1.01 0.25 45 0.94 0.23 50 0.88 0.21 55 0.82 0.20 60 0.78 0.19 75 0.68 0.16 90 0.60 0.15 105 0.55 0.13 120 0.50 0.12 150 0.43 0.11 180 0.39 0.09 360 0.25 0.06 720 0.16 0.04 1440 0.10 103.48 ft3 2.61 (ft3/s) 1675.08 38400.00 ----- 2149.84 76800.00 ----- 1016.94 9600.00 ----- 1305.16 19200.00 ----- 878.82 6400.00 ----- 952.33 8000.00 ----- 792.36 4800.00 ----- 837.58 5600.00 ----- 684.75 3200.00 ----- 742.02 4000.00 ----- 641.25 2666.67 ----- 663.63 2933.33 ----- 591.75 2133.33 ----- 617.38 2400.00 ----- 533.53 1600.00 ----- 563.98 1866.67 ----- 461.07 1066.67 ----- 499.64 1333.33 ----- 359.25 533.33 ----- 415.71 800.00 ----- 156.82 53.33 103.48 279.91 266.67 13.25 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.8957 Cwd x Cf =0.99 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 8 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.85 cfs 5 92 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 24757 0.568 0.9 1.1 0.99 0.99 0.562659091 3305 0.076 0.2 1.1 0.22 0.22 0.016691919 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 28062 0.6442 0.5794 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.58 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 6.21 5 3.83 2.22 10 2.46 1.42 15 1.89 1.10 20 1.58 0.91 25 1.37 0.79 30 1.22 0.70 35 1.10 0.64 40 1.01 0.59 45 0.94 0.54 50 0.88 0.51 55 0.82 0.48 60 0.78 0.45 75 0.68 0.39 90 0.60 0.35 105 0.55 0.32 120 0.50 0.29 150 0.43 0.25 180 0.39 0.22 360 0.25 0.14 720 0.16 0.09 1440 0.10 409.46 ft3 6.21 (ft3/s) 3979.64 36800.00 ----- 5107.58 73600.00 ----- 2416.03 9200.00 ----- 3100.80 18400.00 ----- 2087.90 6133.33 ----- 2262.55 7666.67 ----- 1882.49 4600.00 ----- 1989.91 5366.67 ----- 1626.82 3066.67 ----- 1762.90 3833.33 ----- 1523.47 2555.56 ----- 1576.65 2811.11 ----- 1405.87 2044.44 ----- 1466.77 2300.00 ----- 1267.56 1533.33 ----- 1339.89 1788.89 ----- 1095.41 1022.22 73.18 1187.03 1277.78 ----- 853.50 511.11 342.39 987.64 766.67 220.97 372.57 51.11 321.46 665.02 255.56 409.46 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.8176 Cwd x Cf =0.90 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 9 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.44 cfs 10 23.5 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 12570 0.289 0.9 1.1 0.99 0.99 0.285681818 1804 0.041 0.2 1.1 0.22 0.22 0.009111111 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 14374 0.3300 0.2948 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.29 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 3.16 5 3.83 1.13 10 2.46 0.72 15 1.89 0.56 20 1.58 0.46 25 1.37 0.40 30 1.22 0.36 35 1.10 0.32 40 1.01 0.30 45 0.94 0.28 50 0.88 0.26 55 0.82 0.24 60 0.78 0.23 75 0.68 0.20 90 0.60 0.18 105 0.55 0.16 120 0.50 0.15 150 0.43 0.13 180 0.39 0.11 360 0.25 0.07 720 0.16 0.05 1440 0.10 207.83 ft3 3.16 (ft3/s) 2024.97 18800.00 ----- 2598.90 37600.00 ----- 1229.36 4700.00 ----- 1577.79 9400.00 ----- 1062.39 3133.33 ----- 1151.26 3916.67 ----- 957.87 2350.00 ----- 1012.53 2741.67 ----- 827.78 1566.67 ----- 897.02 1958.33 ----- 775.19 1305.56 ----- 802.25 1436.11 ----- 715.35 1044.44 ----- 746.34 1175.00 ----- 644.98 783.33 ----- 681.78 913.89 ----- 557.38 522.22 35.16 604.00 652.78 ----- 434.29 261.11 173.18 502.54 391.67 110.88 189.57 26.11 163.46 338.38 130.56 207.83 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.8121 Cwd x Cf =0.89 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 10 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.44 cfs 10 24 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 6910 0.159 0.9 1.1 0.99 0.99 0.157045455 286 0.007 0.2 1.1 0.22 0.22 0.001444444 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 7196 0.1652 0.1585 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.16 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 1.70 5 3.83 0.61 10 2.46 0.39 15 1.89 0.30 20 1.58 0.25 25 1.37 0.22 30 1.22 0.19 35 1.10 0.17 40 1.01 0.16 45 0.94 0.15 50 0.88 0.14 55 0.82 0.13 60 0.78 0.12 75 0.68 0.11 90 0.60 0.10 105 0.55 0.09 120 0.50 0.08 150 0.43 0.07 180 0.39 0.06 360 0.25 0.04 720 0.16 0.03 1440 0.10 75.25 ft3 1.70 (ft3/s) Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 11 Surface Type Landscape Totals =0.8722 Cwd x Cf =0.96 Runoff Volume Discharge Volume Site Detention = = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) 101.92 26.67 75.25 181.93 133.33 48.59 233.49 266.67 ----- 270.18 400.00 ----- 299.66 533.33 ----- 324.73 666.67 ----- 346.76 800.00 ----- 366.55 933.33 ----- 384.60 1066.67 ----- 401.26 1200.00 ----- 416.77 1333.33 ----- 431.32 1466.67 ----- 445.04 1600.00 ----- 482.27 2000.00 ----- 514.98 2400.00 ----- 544.37 2800.00 ----- 571.18 3200.00 ----- 618.95 4000.00 ----- 660.94 4800.00 ----- 848.27 9600.00 ----- 1088.69 19200.00 ----- 1397.25 38400.00 ----- = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =1.14 cfs 11 56 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 29513 0.678 0.9 1.1 0.99 0.99 0.67075 22406 0.514 0.2 1.1 0.22 0.22 0.113161616 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 51919 1.1919 0.7839 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.78 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 8.40 5 3.83 3.00 10 2.46 1.92 15 1.89 1.48 20 1.58 1.24 25 1.37 1.07 30 1.22 0.95 35 1.10 0.86 40 1.01 0.79 45 0.94 0.74 50 0.88 0.69 55 0.82 0.65 60 0.78 0.61 75 0.68 0.53 90 0.60 0.47 105 0.55 0.43 120 0.50 0.39 150 0.43 0.34 180 0.39 0.30 360 0.25 0.19 720 0.16 0.12 1440 0.10 557.60 ft3 8.40 (ft3/s) 5384.80 49280.00 ----- 6910.99 98560.00 ----- 3269.10 12320.00 ----- 4195.64 24640.00 ----- 2825.11 8213.33 ----- 3061.42 10266.67 ----- 2547.16 6160.00 ----- 2692.51 7186.67 ----- 2201.22 4106.67 ----- 2385.35 5133.33 ----- 2061.38 3422.22 ----- 2133.34 3764.44 ----- 1902.27 2737.78 ----- 1984.66 3080.00 ----- 1715.12 2053.33 ----- 1812.99 2395.56 ----- 1482.18 1368.89 113.29 1606.16 1711.11 ----- 1154.86 684.44 470.42 1336.36 1026.67 309.69 504.12 68.44 435.67 899.83 342.22 557.60 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.5979 Cwd x Cf =0.66 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 12 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.00 cfs Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 5188 0.119 0.9 1.1 0.99 0.99 0.117909091 0 0.000 0.2 1.1 0.22 0.22 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 5188 0.1191 0.1179 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.12 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 10.72 1.26 5 3.83 0.45 10 2.46 0.29 15 1.89 0.22 20 1.58 0.19 25 1.37 0.16 30 1.22 0.14 35 1.10 0.13 40 1.01 0.12 45 0.94 0.11 50 0.88 0.10 55 0.82 0.10 60 0.78 0.09 75 0.68 0.08 90 0.60 0.07 105 0.55 0.06 120 0.50 0.06 150 0.43 0.05 180 0.39 0.05 360 0.25 0.03 720 0.16 0.02 1440 0.10 1,039.49 ft3 1.26 (ft3/s) 809.93 0.00 809.93 1039.49 0.00 1039.49 491.71 0.00 491.71 631.07 0.00 631.07 424.93 0.00 424.93 460.47 0.00 460.47 383.12 0.00 383.12 404.98 0.00 404.98 331.09 0.00 331.09 358.78 0.00 358.78 310.06 0.00 310.06 320.88 0.00 320.88 286.12 0.00 286.12 298.52 0.00 298.52 257.97 0.00 257.97 272.69 0.00 272.69 222.94 0.00 222.94 241.58 0.00 241.58 173.70 0.00 173.70 201.00 0.00 201.00 75.82 0.00 75.82 135.34 0.00 135.34 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.9000 Cwd x Cf =0.99 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 13 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Area (sq.ft.)Infiltration Rate (in/hr) Discharge Rate, d =0.05 cfs 28.27433388 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 7336 0.168 0.9 1.1 0.99 0.99 0.166727273 5468 0.126 0.2 1.1 0.22 0.22 0.027616162 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 12804 0.2939 0.1943 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.19 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 2.08 5 3.83 0.74 10 2.46 0.48 15 1.89 0.37 20 1.58 0.31 25 1.37 0.27 30 1.22 0.24 35 1.10 0.21 40 1.01 0.20 45 0.94 0.18 50 0.88 0.17 55 0.82 0.16 60 0.78 0.15 75 0.68 0.13 90 0.60 0.12 105 0.55 0.11 120 0.50 0.10 150 0.43 0.08 180 0.39 0.08 360 0.25 0.05 720 0.16 0.03 1440 0.10 357.22 ft3 2.08 (ft3/s) 1334.97 2261.95 ----- 1713.34 4523.89 ----- 810.46 565.49 244.97 1040.16 1130.97 ----- 700.39 376.99 323.40 758.97 471.24 287.73 631.48 282.74 348.74 667.51 329.87 337.65 545.72 188.50 357.22 591.36 235.62 355.74 511.05 157.08 353.97 528.89 172.79 356.10 471.60 125.66 345.94 492.03 141.37 350.66 425.20 94.25 330.96 449.47 109.96 339.51 367.45 62.83 304.62 398.19 78.54 319.65 286.31 31.42 254.89 331.30 47.12 284.18 124.98 3.14 121.84 223.08 15.71 207.37 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.6011 Cwd x Cf =0.66 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 14 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.36 cfs 4 48.47 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 10016 0.230 0.9 1.1 0.99 0.99 0.227636364 157 0.004 0.2 1.1 0.22 0.22 0.000792929 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 10173 0.2335 0.2284 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.23 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 2.45 5 3.83 0.87 10 2.46 0.56 15 1.89 0.43 20 1.58 0.36 25 1.37 0.31 30 1.22 0.28 35 1.10 0.25 40 1.01 0.23 45 0.94 0.21 50 0.88 0.20 55 0.82 0.19 60 0.78 0.18 75 0.68 0.15 90 0.60 0.14 105 0.55 0.12 120 0.50 0.11 150 0.43 0.10 180 0.39 0.09 360 0.25 0.06 720 0.16 0.04 1440 0.10 154.50 ft3 2.45 (ft3/s) 1569.11 15510.40 ----- 2013.84 31020.80 ----- 952.60 3877.60 ----- 1222.60 7755.20 ----- 823.23 2585.07 ----- 892.09 3231.33 ----- 742.24 1938.80 ----- 784.59 2261.93 ----- 641.43 1292.53 ----- 695.08 1615.67 ----- 600.68 1077.11 ----- 621.65 1184.82 ----- 554.31 861.69 ----- 578.32 969.40 ----- 499.78 646.27 ----- 528.30 753.98 ----- 431.90 430.84 1.06 468.03 538.56 ----- 336.52 215.42 121.10 389.41 323.13 66.28 146.90 21.54 125.36 262.21 107.71 154.50 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.8892 Cwd x Cf =0.98 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 15 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.72 cfs 8 48.45 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 19677 0.452 0.9 1.1 0.99 0.99 0.447204545 5382 0.124 0.2 1.1 0.22 0.22 0.027181818 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 25059 0.5753 0.4744 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.47 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 10.72 5.08 5 3.83 1.82 10 2.46 1.16 15 1.89 0.90 20 1.58 0.75 25 1.37 0.65 30 1.22 0.58 35 1.10 0.52 40 1.01 0.48 45 0.94 0.44 50 0.88 0.42 55 0.82 0.39 60 0.78 0.37 75 0.68 0.32 90 0.60 0.29 105 0.55 0.26 120 0.50 0.24 150 0.43 0.21 180 0.39 0.18 360 0.25 0.12 720 0.16 0.08 1440 0.10 329.20 ft3 5.08 (ft3/s) 3258.63 31008.00 ----- 4182.21 62016.00 ----- 1978.30 7752.00 ----- 2539.01 15504.00 ----- 1709.62 5168.00 ----- 1852.63 6460.00 ----- 1541.42 3876.00 ----- 1629.38 4522.00 ----- 1332.08 2584.00 ----- 1443.50 3230.00 ----- 1247.45 2153.33 ----- 1291.00 2368.67 ----- 1151.16 1722.67 ----- 1201.02 1938.00 ----- 1037.91 1292.00 ----- 1097.13 1507.33 ----- 896.94 861.33 35.61 971.97 1076.67 ----- 698.87 430.67 268.20 808.70 646.00 162.70 305.07 43.07 262.00 544.53 215.33 329.20 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.7497 Cwd x Cf =0.82 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 16 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.89 cfs 5 96 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 16355 0.375 0.9 1.1 0.99 0.99 0.371704545 912 0.021 0.2 1.1 0.22 0.22 0.004606061 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 17267 0.3964 0.3763 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.38 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 4.03 5 3.83 1.44 10 2.46 0.92 15 1.89 0.71 20 1.58 0.59 25 1.37 0.51 30 1.22 0.46 35 1.10 0.41 40 1.01 0.38 45 0.94 0.35 50 0.88 0.33 55 0.82 0.31 60 0.78 0.29 75 0.68 0.25 90 0.60 0.23 105 0.55 0.21 120 0.50 0.19 150 0.43 0.16 180 0.39 0.15 360 0.25 0.09 720 0.16 0.06 1440 0.10 188.66 ft3 4.03 (ft3/s) 2584.93 38400.00 ----- 3317.57 76800.00 ----- 1569.30 9600.00 ----- 2014.09 19200.00 ----- 1356.17 6400.00 ----- 1469.61 8000.00 ----- 1222.75 4800.00 ----- 1292.52 5600.00 ----- 1056.68 3200.00 ----- 1145.07 4000.00 ----- 989.55 2666.67 ----- 1024.09 2933.33 ----- 913.17 2133.33 ----- 952.72 2400.00 ----- 823.33 1600.00 ----- 870.31 1866.67 ----- 711.51 1066.67 ----- 771.02 1333.33 ----- 554.38 533.33 21.05 641.51 800.00 ----- 242.00 53.33 188.66 431.95 266.67 165.29 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.8630 Cwd x Cf =0.95 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 17 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.52 cfs 5 56 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 4820 0.111 0.9 1.1 0.99 0.99 0.109545455 5 0.000 0.2 1.1 0.22 0.22 2.52525E-05 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 4825 0.1108 0.1096 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.11 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 1.17 5 3.83 0.42 10 2.46 0.27 15 1.89 0.21 20 1.58 0.17 25 1.37 0.15 30 1.22 0.13 35 1.10 0.12 40 1.01 0.11 45 0.94 0.10 50 0.88 0.10 55 0.82 0.09 60 0.78 0.09 75 0.68 0.07 90 0.60 0.07 105 0.55 0.06 120 0.50 0.05 150 0.43 0.05 180 0.39 0.04 360 0.25 0.03 720 0.16 0.02 1440 0.10 39.35 ft3 1.17 (ft3/s) 752.66 22400.00 ----- 965.98 44800.00 ----- 456.94 5600.00 ----- 586.44 11200.00 ----- 394.88 3733.33 ----- 427.91 4666.67 ----- 356.03 2800.00 ----- 376.34 3266.67 ----- 307.67 1866.67 ----- 333.41 2333.33 ----- 288.13 1555.56 ----- 298.19 1711.11 ----- 265.89 1244.44 ----- 277.40 1400.00 ----- 239.73 933.33 ----- 253.41 1088.89 ----- 207.17 622.22 ----- 224.50 777.78 ----- 161.42 311.11 ----- 186.79 466.67 ----- 70.46 31.11 39.35 125.77 155.56 ----- = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.8993 Cwd x Cf =0.99 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 19 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.98 cfs 5 106 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 19013 0.436 0.9 1.1 0.99 0.99 0.432113636 1499 0.034 0.2 1.1 0.22 0.22 0.007570707 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 20512 0.4709 0.4397 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.44 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 4.71 5 3.83 1.68 10 2.46 1.08 15 1.89 0.83 20 1.58 0.69 25 1.37 0.60 30 1.22 0.53 35 1.10 0.48 40 1.01 0.44 45 0.94 0.41 50 0.88 0.39 55 0.82 0.36 60 0.78 0.34 75 0.68 0.30 90 0.60 0.26 105 0.55 0.24 120 0.50 0.22 150 0.43 0.19 180 0.39 0.17 360 0.25 0.11 720 0.16 0.07 1440 0.10 223.86 ft3 4.71 (ft3/s) 3020.25 42400.00 ----- 3876.27 84800.00 ----- 1833.59 10600.00 ----- 2353.27 21200.00 ----- 1584.56 7066.67 ----- 1717.10 8833.33 ----- 1428.67 5300.00 ----- 1510.19 6183.33 ----- 1234.63 3533.33 ----- 1337.91 4416.67 ----- 1156.20 2944.44 ----- 1196.56 3238.89 ----- 1066.95 2355.56 ----- 1113.17 2650.00 ----- 961.98 1766.67 ----- 1016.88 2061.11 ----- 831.33 1177.78 ----- 900.87 1472.22 ----- 647.74 588.89 58.86 749.54 883.33 ----- 282.75 58.89 223.86 504.70 294.44 210.26 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.8488 Cwd x Cf =0.93 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 20 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =2.89 cfs 5 312 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 27598 0.634 0.9 1.1 0.99 0.99 0.627227273 0 0.000 0.2 1.1 0.22 0.22 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 27598 0.6336 0.6272 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.63 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 6.72 5 3.83 2.40 10 2.46 1.54 15 1.89 1.19 20 1.58 0.99 25 1.37 0.86 30 1.22 0.76 35 1.10 0.69 40 1.01 0.63 45 0.94 0.59 50 0.88 0.55 55 0.82 0.52 60 0.78 0.49 75 0.68 0.42 90 0.60 0.38 105 0.55 0.34 120 0.50 0.31 150 0.43 0.27 180 0.39 0.24 360 0.25 0.16 720 0.16 0.10 1440 0.10 230.02 ft3 6.72 (ft3/s) 4308.51 124800.00 ----- 5529.66 249600.00 ----- 2615.69 31200.00 ----- 3357.04 62400.00 ----- 2260.44 20800.00 ----- 2449.52 26000.00 ----- 2038.05 15600.00 ----- 2154.35 18200.00 ----- 1761.25 10400.00 ----- 1908.58 13000.00 ----- 1649.37 8666.67 ----- 1706.94 9533.33 ----- 1522.05 6933.33 ----- 1587.98 7800.00 ----- 1372.31 5200.00 ----- 1450.61 6066.67 ----- 1185.93 3466.67 ----- 1285.13 4333.33 ----- 924.03 1733.33 ----- 1069.25 2600.00 ----- 403.36 173.33 230.02 719.97 866.67 ----- = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.9000 Cwd x Cf =0.99 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 21 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =3.23 cfs 5 349 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 49197 1.129 0.9 1.1 0.99 0.99 1.118113636 14200 0.326 0.2 1.1 0.22 0.22 0.071717172 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 63397 1.4554 1.1898 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =1.19 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 12.75 5 3.83 4.55 10 2.46 2.92 15 1.89 2.25 20 1.58 1.87 25 1.37 1.63 30 1.22 1.45 35 1.10 1.31 40 1.01 1.20 45 0.94 1.12 50 0.88 1.04 55 0.82 0.98 60 0.78 0.93 75 0.68 0.80 90 0.60 0.72 105 0.55 0.65 120 0.50 0.60 150 0.43 0.52 180 0.39 0.46 360 0.25 0.29 720 0.16 0.19 1440 0.10 571.26 ft3 12.75 (ft3/s) 8173.11 139600.00 ----- 10489.59 279200.00 ----- 4961.88 34900.00 ----- 6368.20 69800.00 ----- 4287.98 23266.67 ----- 4646.66 29083.33 ----- 3866.12 17450.00 ----- 4086.73 20358.33 ----- 3341.04 11633.33 ----- 3620.51 14541.67 ----- 3128.79 9694.44 ----- 3238.01 10663.89 ----- 2887.28 7755.56 ----- 3012.34 8725.00 ----- 2603.22 5816.67 ----- 2751.77 6786.11 ----- 2249.67 3877.78 ----- 2437.85 4847.22 ----- 1752.86 1938.89 ----- 2028.34 2908.33 ----- 765.15 193.89 571.26 1365.77 969.44 396.32 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.7432 Cwd x Cf =0.82 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 22 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.52 cfs 8 35 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 13403 0.308 0.9 1.1 0.99 0.99 0.304613636 5835 0.134 0.2 1.1 0.22 0.22 0.029469697 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 19238 0.4416 0.3341 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.33 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 3.58 5 3.83 1.28 10 2.46 0.82 15 1.89 0.63 20 1.58 0.53 25 1.37 0.46 30 1.22 0.41 35 1.10 0.37 40 1.01 0.34 45 0.94 0.31 50 0.88 0.29 55 0.82 0.28 60 0.78 0.26 75 0.68 0.23 90 0.60 0.20 105 0.55 0.18 120 0.50 0.17 150 0.43 0.14 180 0.39 0.13 360 0.25 0.08 720 0.16 0.05 1440 0.10 227.93 ft3 3.58 (ft3/s) 2294.87 22400.00 ----- 2945.29 44800.00 ----- 1393.21 5600.00 ----- 1788.08 11200.00 ----- 1203.99 3733.33 ----- 1304.70 4666.67 ----- 1085.54 2800.00 ----- 1147.48 3266.67 ----- 938.11 1866.67 ----- 1016.58 2333.33 ----- 878.51 1555.56 ----- 909.18 1711.11 ----- 810.70 1244.44 ----- 845.81 1400.00 ----- 730.94 933.33 ----- 772.65 1088.89 ----- 631.67 622.22 9.44 684.50 777.78 ----- 492.17 311.11 181.06 569.52 466.67 102.86 214.84 31.11 183.73 383.48 155.56 227.93 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.6877 Cwd x Cf =0.76 Runoff Volume Discharge Volume Site Detention Landscape Totals = RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 23 Surface Type Impervious = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.26 cfs 5 28 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 6039 0.139 0.9 1.1 0.99 0.99 0.13725 2608 0.060 0.2 1.1 0.22 0.22 0.013171717 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 8647 0.1985 0.1504 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.15 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 1.61 5 3.83 0.58 10 2.46 0.37 15 1.89 0.28 20 1.58 0.24 25 1.37 0.21 30 1.22 0.18 35 1.10 0.17 40 1.01 0.15 45 0.94 0.14 50 0.88 0.13 55 0.82 0.12 60 0.78 0.12 75 0.68 0.10 90 0.60 0.09 105 0.55 0.08 120 0.50 0.08 150 0.43 0.07 180 0.39 0.06 360 0.25 0.04 720 0.16 0.02 1440 0.10 94.89 ft3 1.61 (ft3/s) 1033.27 11200.00 ----- 1326.12 22400.00 ----- 627.29 2800.00 ----- 805.09 5600.00 ----- 542.10 1866.67 ----- 587.44 2333.33 ----- 488.77 1400.00 ----- 516.66 1633.33 ----- 422.38 933.33 ----- 457.72 1166.67 ----- 395.55 777.78 ----- 409.36 855.56 ----- 365.02 622.22 ----- 380.83 700.00 ----- 329.11 466.67 ----- 347.89 544.44 ----- 284.41 311.11 ----- 308.20 388.89 ----- 221.60 155.56 66.05 256.43 233.33 23.10 96.73 15.56 81.18 172.66 77.78 94.89 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.6889 Cwd x Cf =0.76 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 27 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.57 cfs 11 28 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 13603 0.312 0.9 1.1 0.99 0.99 0.309159091 10164 0.233 0.2 1.1 0.22 0.22 0.051333333 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 23767 0.5456 0.3605 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.36 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 3.86 5 3.83 1.38 10 2.46 0.89 15 1.89 0.68 20 1.58 0.57 25 1.37 0.49 30 1.22 0.44 35 1.10 0.40 40 1.01 0.36 45 0.94 0.34 50 0.88 0.32 55 0.82 0.30 60 0.78 0.28 75 0.68 0.24 90 0.60 0.22 105 0.55 0.20 120 0.50 0.18 150 0.43 0.16 180 0.39 0.14 360 0.25 0.09 720 0.16 0.06 1440 0.10 242.69 ft3 3.86 (ft3/s) 2476.27 24640.00 ----- 3178.11 49280.00 ----- 1503.34 6160.00 ----- 1929.42 12320.00 ----- 1299.16 4106.67 ----- 1407.83 5133.33 ----- 1171.35 3080.00 ----- 1238.19 3593.33 ----- 1012.26 2053.33 ----- 1096.93 2566.67 ----- 947.96 1711.11 ----- 981.05 1882.22 ----- 874.78 1368.89 ----- 912.67 1540.00 ----- 788.72 1026.67 ----- 833.73 1197.78 ----- 681.60 684.44 ----- 738.61 855.56 ----- 531.08 342.22 188.86 614.54 513.33 101.21 231.82 34.22 197.60 413.80 171.11 242.69 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.6006 Cwd x Cf =0.66 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 29 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =3.40 cfs 5 367 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 74433 1.709 0.9 1.1 0.99 0.99 1.691659091 49194 1.129 0.2 1.1 0.22 0.22 0.248454545 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 123627 2.8381 1.9401 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =1.94 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 10.72 20.79 5 3.83 7.42 10 2.46 4.76 15 1.89 3.67 20 1.58 3.06 25 1.37 2.65 30 1.22 2.36 35 1.10 2.14 40 1.01 1.96 45 0.94 1.82 50 0.88 1.70 55 0.82 1.60 60 0.78 1.51 75 0.68 1.31 90 0.60 1.17 105 0.55 1.06 120 0.50 0.97 150 0.43 0.84 180 0.39 0.75 360 0.25 0.48 720 0.16 0.31 1440 0.10 1,207.55 ft3 20.79 (ft3/s) 13326.91 146800.00 ----- 17104.10 293600.00 ----- 8090.73 36700.00 ----- 10383.86 73400.00 ----- 6991.90 24466.67 ----- 7576.75 30583.33 ----- 6304.01 18350.00 ----- 6663.74 21408.33 ----- 5447.84 12233.33 ----- 5903.53 15291.67 ----- 5101.75 10194.44 ----- 5279.84 11213.89 ----- 4707.95 8155.56 ----- 4911.86 9175.00 ----- 4244.76 6116.67 ----- 4486.98 7136.11 ----- 3668.26 4077.78 ----- 3975.10 5097.22 ----- 2858.18 2038.89 819.29 3307.37 3058.33 249.04 1247.64 203.89 1043.75 2226.99 1019.44 1207.55 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.6215 Cwd x Cf =0.68 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 28 & 30 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.89 cfs 5 96 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 9307 0.214 0.9 1.1 0.99 0.99 0.211522727 387 0.009 0.2 1.1 0.22 0.22 0.001954545 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 9694 0.2225 0.2135 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.21 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 2.29 5 3.83 0.82 10 2.46 0.52 15 1.89 0.40 20 1.58 0.34 25 1.37 0.29 30 1.22 0.26 35 1.10 0.24 40 1.01 0.22 45 0.94 0.20 50 0.88 0.19 55 0.82 0.18 60 0.78 0.17 75 0.68 0.14 90 0.60 0.13 105 0.55 0.12 120 0.50 0.11 150 0.43 0.09 180 0.39 0.08 360 0.25 0.05 720 0.16 0.03 1440 0.10 83.95 ft3 2.29 (ft3/s) 1466.41 38400.00 ----- 1882.02 76800.00 ----- 890.25 9600.00 ----- 1142.57 19200.00 ----- 769.34 6400.00 ----- 833.69 8000.00 ----- 693.65 4800.00 ----- 733.23 5600.00 ----- 599.44 3200.00 ----- 649.59 4000.00 ----- 561.36 2666.67 ----- 580.96 2933.33 ----- 518.03 2133.33 ----- 540.47 2400.00 ----- 467.07 1600.00 ----- 493.72 1866.67 ----- 403.63 1066.67 ----- 437.39 1333.33 ----- 314.50 533.33 ----- 363.92 800.00 ----- 137.28 53.33 83.95 245.04 266.67 ----- = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.8721 Cwd x Cf =0.96 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 31 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =2.33 cfs 18 70 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 65187 1.496 0.9 1.1 0.99 0.99 1.481522727 35493 0.815 0.2 1.1 0.22 0.22 0.179257576 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 100680 2.3113 1.6608 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =1.66 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 10.72 17.80 5 3.83 6.35 10 2.46 4.08 15 1.89 3.15 20 1.58 2.62 25 1.37 2.27 30 1.22 2.02 35 1.10 1.83 40 1.01 1.68 45 0.94 1.56 50 0.88 1.46 55 0.82 1.37 60 0.78 1.30 75 0.68 1.12 90 0.60 1.00 105 0.55 0.91 120 0.50 0.83 150 0.43 0.72 180 0.39 0.64 360 0.25 0.41 720 0.16 0.26 1440 0.10 1,206.36 ft3 17.80 (ft3/s) 11408.13 100800.00 ----- 14641.49 201600.00 ----- 6925.85 25200.00 ----- 8888.81 50400.00 ----- 5985.22 16800.00 ----- 6485.86 21000.00 ----- 5396.38 12600.00 ----- 5704.31 14700.00 ----- 4663.47 8400.00 ----- 5053.55 10500.00 ----- 4367.21 7000.00 ----- 4519.66 7700.00 ----- 4030.11 5600.00 ----- 4204.66 6300.00 ----- 3633.61 4200.00 ----- 3840.96 4900.00 ----- 3140.12 2800.00 340.12 3402.78 3500.00 ----- 2446.67 1400.00 1046.67 2831.18 2100.00 731.18 1068.01 140.00 928.01 1906.36 700.00 1206.36 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.6532 Cwd x Cf =0.72 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 32, 25, 26 & 39 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =1.03 cfs 5 111 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 14315 0.329 0.9 1.1 0.99 0.99 0.325340909 11621 0.267 0.2 1.1 0.22 0.22 0.058691919 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 25936 0.5954 0.3840 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.38 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 4.12 5 3.83 1.47 10 2.46 0.94 15 1.89 0.73 20 1.58 0.61 25 1.37 0.52 30 1.22 0.47 35 1.10 0.42 40 1.01 0.39 45 0.94 0.36 50 0.88 0.34 55 0.82 0.32 60 0.78 0.30 75 0.68 0.26 90 0.60 0.23 105 0.55 0.21 120 0.50 0.19 150 0.43 0.17 180 0.39 0.15 360 0.25 0.10 720 0.16 0.06 1440 0.10 185.30 ft3 4.12 (ft3/s) 2637.98 44400.00 ----- 3385.65 88800.00 ----- 1601.51 11100.00 ----- 2055.42 22200.00 ----- 1384.00 7400.00 ----- 1499.77 9250.00 ----- 1247.84 5550.00 ----- 1319.04 6475.00 ----- 1078.36 3700.00 ----- 1168.57 4625.00 ----- 1009.86 3083.33 ----- 1045.11 3391.67 ----- 931.91 2466.67 ----- 972.27 2775.00 ----- 840.22 1850.00 ----- 888.17 2158.33 ----- 726.11 1233.33 ----- 786.85 1541.67 ----- 565.76 616.67 ----- 654.67 925.00 ----- 246.96 61.67 185.30 440.82 308.33 132.49 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.5864 Cwd x Cf =0.64 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 33 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Area (sq.ft.)Infiltration Rate (in/hr) Discharge Rate, d =0.10 cfs 56.5 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 9803 0.225 0.9 1.1 0.99 0.99 0.222795455 2241 0.051 0.2 1.1 0.22 0.22 0.011318182 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 12044 0.2765 0.2341 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.23 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 2.51 5 3.83 0.90 10 2.46 0.57 15 1.89 0.44 20 1.58 0.37 25 1.37 0.32 30 1.22 0.28 35 1.10 0.26 40 1.01 0.24 45 0.94 0.22 50 0.88 0.21 55 0.82 0.19 60 0.78 0.18 75 0.68 0.16 90 0.60 0.14 105 0.55 0.13 120 0.50 0.12 150 0.43 0.10 180 0.39 0.09 360 0.25 0.06 720 0.16 0.04 1440 0.10 323.72 ft3 2.51 (ft3/s) 1608.16 4523.89 ----- 2063.95 9047.79 ----- 976.31 1130.97 ----- 1253.02 2261.95 ----- 843.71 753.98 89.73 914.29 942.48 ----- 760.71 565.49 195.22 804.11 659.73 144.38 657.39 376.99 280.40 712.38 471.24 241.14 615.63 314.16 301.47 637.12 345.58 291.54 568.11 251.33 316.78 592.71 282.74 309.97 512.22 188.50 323.72 541.44 219.91 321.53 442.65 125.66 316.99 479.68 157.08 322.60 344.90 62.83 282.07 399.10 94.25 304.85 150.55 6.28 144.27 268.73 31.42 237.32 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.7698 Cwd x Cf =0.85 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 34 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =1.20 cfs 5 130 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 15733 0.361 0.9 1.1 0.99 0.99 0.357568182 0 0.000 0.2 1.1 0.22 0.22 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 15733 0.3612 0.3576 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.36 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 3.83 5 3.83 1.37 10 2.46 0.88 15 1.89 0.68 20 1.58 0.56 25 1.37 0.49 30 1.22 0.43 35 1.10 0.39 40 1.01 0.36 45 0.94 0.34 50 0.88 0.31 55 0.82 0.29 60 0.78 0.28 75 0.68 0.24 90 0.60 0.22 105 0.55 0.19 120 0.50 0.18 150 0.43 0.16 180 0.39 0.14 360 0.25 0.09 720 0.16 0.06 1440 0.10 157.72 ft3 3.83 (ft3/s) 2456.19 52000.00 ----- 3152.33 104000.00 ----- 1491.14 13000.00 ----- 1913.77 26000.00 ----- 1288.63 8666.67 ----- 1396.41 10833.33 ----- 1161.85 6500.00 ----- 1228.15 7583.33 ----- 1004.05 4333.33 ----- 1088.04 5416.67 ----- 940.27 3611.11 ----- 973.09 3972.22 ----- 867.69 2888.89 ----- 905.27 3250.00 ----- 782.32 2166.67 ----- 826.96 2527.78 ----- 676.07 1444.44 ----- 732.62 1805.56 ----- 526.77 722.22 ----- 609.56 1083.33 ----- 229.94 72.22 157.72 410.44 361.11 49.33 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.9000 Cwd x Cf =0.99 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 35 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =2.55 cfs 5 275 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 63080 1.448 0.9 1.1 0.99 0.99 1.433636364 3866 0.089 0.2 1.1 0.22 0.22 0.019525253 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 66946 1.5369 1.4532 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =1.45 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 15.57 5 3.83 5.56 10 2.46 3.57 15 1.89 2.75 20 1.58 2.29 25 1.37 1.98 30 1.22 1.77 35 1.10 1.60 40 1.01 1.47 45 0.94 1.36 50 0.88 1.27 55 0.82 1.20 60 0.78 1.13 75 0.68 0.98 90 0.60 0.87 105 0.55 0.79 120 0.50 0.73 150 0.43 0.63 180 0.39 0.56 360 0.25 0.36 720 0.16 0.23 1440 0.10 904.15 ft3 15.57 (ft3/s) 9981.97 110000.00 ----- 12811.12 220000.00 ----- 6060.03 27500.00 ----- 7777.60 55000.00 ----- 5236.99 18333.33 ----- 5675.05 22916.67 ----- 4721.76 13750.00 ----- 4991.20 16041.67 ----- 4080.48 9166.67 ----- 4421.80 11458.33 ----- 3821.25 7638.89 ----- 3954.64 8402.78 ----- 3526.29 6111.11 ----- 3679.03 6875.00 ----- 3179.36 4583.33 ----- 3360.79 5347.22 ----- 2747.56 3055.56 ----- 2977.38 3819.44 ----- 2140.80 1527.78 613.02 2477.25 2291.67 185.58 934.49 152.78 781.72 1668.04 763.89 904.15 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.8596 Cwd x Cf =0.95 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 36 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.47 cfs 5 51 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 6891 0.158 0.9 1.1 0.99 0.99 0.156613636 1305 0.030 0.2 1.1 0.22 0.22 0.006590909 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 8196 0.1882 0.1632 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.16 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 1.75 5 3.83 0.62 10 2.46 0.40 15 1.89 0.31 20 1.58 0.26 25 1.37 0.22 30 1.22 0.20 35 1.10 0.18 40 1.01 0.17 45 0.94 0.15 50 0.88 0.14 55 0.82 0.13 60 0.78 0.13 75 0.68 0.11 90 0.60 0.10 105 0.55 0.09 120 0.50 0.08 150 0.43 0.07 180 0.39 0.06 360 0.25 0.04 720 0.16 0.03 1440 0.10 76.62 ft3 1.75 (ft3/s) 1121.07 20400.00 ----- 1438.82 40800.00 ----- 680.60 5100.00 ----- 873.50 10200.00 ----- 588.17 3400.00 ----- 637.36 4250.00 ----- 530.30 2550.00 ----- 560.56 2975.00 ----- 458.28 1700.00 ----- 496.61 2125.00 ----- 429.16 1416.67 ----- 444.15 1558.33 ----- 396.04 1133.33 ----- 413.19 1275.00 ----- 357.07 850.00 ----- 377.45 991.67 ----- 308.58 566.67 ----- 334.39 708.33 ----- 240.43 283.33 ----- 278.22 425.00 ----- 104.95 28.33 76.62 187.34 141.67 45.67 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.7885 Cwd x Cf =0.87 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 37 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.39 cfs 5 42 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 3567 0.082 0.9 1.1 0.99 0.99 0.081068182 405 0.009 0.2 1.1 0.22 0.22 0.002045455 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 3972 0.0912 0.0831 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.08 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 0.89 5 3.83 0.32 10 2.46 0.20 15 1.89 0.16 20 1.58 0.13 25 1.37 0.11 30 1.22 0.10 35 1.10 0.09 40 1.01 0.08 45 0.94 0.08 50 0.88 0.07 55 0.82 0.07 60 0.78 0.06 75 0.68 0.06 90 0.60 0.05 105 0.55 0.05 120 0.50 0.04 150 0.43 0.04 180 0.39 0.03 360 0.25 0.02 720 0.16 0.01 1440 0.10 30.12 ft3 0.89 (ft3/s) 570.92 16800.00 ----- 732.73 33600.00 ----- 346.60 4200.00 ----- 444.84 8400.00 ----- 299.53 2800.00 ----- 324.58 3500.00 ----- 270.06 2100.00 ----- 285.47 2450.00 ----- 233.38 1400.00 ----- 252.90 1750.00 ----- 218.56 1166.67 ----- 226.19 1283.33 ----- 201.69 933.33 ----- 210.42 1050.00 ----- 181.84 700.00 ----- 192.22 816.67 ----- 157.15 466.67 ----- 170.29 583.33 ----- 122.44 233.33 ----- 141.69 350.00 ----- 53.45 23.33 30.12 95.40 116.67 ----- = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.8286 Cwd x Cf =0.91 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 38 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =10 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.00 cfs 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 45038 1.034 0.9 1 0.90 0.90 0.93053719 14198 0.326 0.2 1 0.20 0.20 0.065188246 0 1 0.00 0.00 0 0 1 0.00 0.00 0 0 1 0.00 0.00 0 59236 1.3599 0.9957 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =1.00 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 9.16 9.12 5 3.22 3.20 10 2.05 2.04 15 1.58 1.57 20 1.31 1.30 25 1.13 1.13 30 1.00 1.00 35 0.91 0.90 40 0.83 0.83 45 0.77 0.77 50 0.72 0.72 55 0.68 0.67 60 0.64 0.64 75 0.55 0.55 90 0.49 0.49 105 0.44 0.44 120 0.41 0.41 150 0.35 0.35 180 0.31 0.31 360 0.20 0.20 720 0.13 0.13 1440 0.08 2,924.04 ft3 9.12 (ft3/s) 5474.39 0.00 5474.39 6977.44 0.00 6977.44 3369.88 0.00 3369.88 4295.12 0.00 4295.12 2924.04 0.00 2924.04 3161.56 0.00 3161.56 2643.95 0.00 2643.95 2790.52 0.00 2790.52 2294.15 0.00 2294.15 2480.51 0.00 2480.51 2152.33 0.00 2152.33 2225.34 0.00 2225.34 1990.63 0.00 1990.63 2074.40 0.00 2074.40 1799.95 0.00 1799.95 1899.73 0.00 1899.73 1561.82 0.00 1561.82 1688.68 0.00 1688.68 1225.38 0.00 1225.38 1412.22 0.00 1412.22 547.36 0.00 547.36 961.41 0.00 961.41 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.7322 Cwd x Cf =0.73 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed 40 & 41 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =10 years Unit Width (ft)Unit Length (ft)Infiltration Rate (in/hr) Discharge Rate, d =0.63 cfs 4 85 80 Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C'C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 0 0.000 0 1 0.00 0.00 0 0 1 0.00 0.00 0 0 1 0.00 0.00 0 0 1 0.00 0.00 0 0 1 0.00 0.00 0 0 0.0000 0.0000 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj = Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 9.16 5 3.22 10 2.05 15 1.58 20 1.31 25 1.13 30 1.00 35 0.91 40 0.83 45 0.77 50 0.72 55 0.68 60 0.64 75 0.55 90 0.49 105 0.44 120 0.41 150 0.35 180 0.31 360 0.20 720 0.13 1440 0.08 153.67 ft3 - (ft3/s) 4687.00 4533.33 153.67 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.0000 Cwd x Cf = Runoff Volume Discharge Volume Site Detention = Totals N/A RATIONAL METHOD FOR RUNOFF CALCULATIONS Post-Project Watershed Ferguson Farms Deficient Volume Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Discharge Rate, d = cfs Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 16158 0.371 0.9 1.1 0.99 0.99 0.367227273 0.000 0.2 1.1 0.22 0.22 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 16158 0.3709 0.3672 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.37 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 10.72 3.94 5 3.83 1.41 10 2.46 0.90 15 1.89 0.70 20 1.58 0.58 25 1.37 0.50 30 1.22 0.45 35 1.10 0.40 40 1.01 0.37 45 0.94 0.34 50 0.88 0.32 55 0.82 0.30 60 0.78 0.29 75 0.68 0.25 90 0.60 0.22 105 0.55 0.20 120 0.50 0.18 150 0.43 0.16 180 0.39 0.14 360 0.25 0.09 720 0.16 0.06 1440 0.10 1.41 (ft3/s) 2522.54 0.00 2522.54 3237.49 0.00 3237.49 1531.42 0.00 1531.42 1965.47 0.00 1965.47 1323.44 0.00 1323.44 1434.14 0.00 1434.14 1193.23 0.00 1193.23 1261.32 0.00 1261.32 1031.17 0.00 1031.17 1117.43 0.00 1117.43 965.67 0.00 965.67 999.37 0.00 999.37 891.13 0.00 891.13 929.72 0.00 929.72 803.45 0.00 803.45 849.30 0.00 849.30 694.33 0.00 694.33 752.41 0.00 752.41 541.00 0.00 541.00 626.02 0.00 626.02 236.16 0.00 236.16 421.53 0.00 421.53 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3) (ft 3) (ft 3) = 0.9000 Cwd x Cf =0.99 Runoff Volume Discharge Volume Site Detention Landscape Totals = RATIONAL METHOD FOR RUNOFF CALCULATIONS Resort Drive Analysis Surface Type Impervious = Label Solve For Discharge (ft³/s) Spread (ft) ResortDriveInlet Spread 1.41 2.12 Gutter Width (ft) Gutter Cross Slope (ft/ft) Road Cross Slope (ft/ft) Local Depression (in) 3.50 0.10 0.02 2.00 Local Depression Width (ft) Grate Width (ft) Grate Length (ft) Grate Type 3.00 1.00 3.00 45˚ Tilt Bar Clogging (%) Curb Opening Length (ft) Opening Height (ft) Curb Throat Type 0.00 3.00 0.33 Horizontal Throat Incline Angle (degrees) Depth (ft) Gutter Depression (ft) Total Depression (ft) 90.00 0.16 0.28 0.45 Open Grate Area (ft²) Active Grate Weir Length (ft) Calculation Option Notes 1.02 5.00 Use Both Messages Resort Drive Sag Inlet (SAGINLET.fm8) Report 10/03/2018 2:24:41 PM Bentley Systems, Inc. Haestad Methods Solution CenterBentley FlowMaster V8i (SELECTseries 1) [08.11.01.03] 27 Siemons Company Drive Suite 200 W Watertown, CT 06795 USA +1-203-755-1666 2of1Page TABLE I-1: Runoff Coefficients for Use in the Rational Method LAND USE RUNOFF COEFFICIENTS, C Open Land 0.2 Low to Medium Density Residential 0.35 Dense Residential 0.5 Commercial Neighborhood 0.6 Commercial Downtown 0.8 Industrial 0.8 Design Standards and Specifications Policy City of Bozeman, March 2004 as Amended RAINFALL INTENSITY-DURATION CURVES (Figures I-2, I-3) Time 2 5 10 25 50 100 (min)(in/hr)(in/hr)(in/hr)(in/hr)(in/hr)(in/hr) 1 4.20 7.15 9.16 10.72 13.72 15.69 5 1.60 2.55 3.22 3.83 4.74 5.34 10 1.05 1.64 2.05 2.46 3.00 3.35 15 0.83 1.26 1.58 1.89 2.30 2.56 20 0.70 1.05 1.31 1.58 1.90 2.11 25 0.61 0.91 1.13 1.37 1.64 1.82 30 0.55 0.81 1.00 1.22 1.45 1.61 35 0.50 0.73 0.91 1.10 1.31 1.45 40 0.46 0.67 0.83 1.01 1.20 1.33 45 0.43 0.63 0.77 0.94 1.11 1.22 50 0.40 0.58 0.72 0.88 1.04 1.14 55 0.38 0.55 0.68 0.82 0.97 1.07 60 0.36 0.52 0.64 0.78 0.92 1.01 75 0.31 0.45 0.55 0.68 0.79 0.87 90 0.28 0.40 0.49 0.60 0.70 0.77 105 0.26 0.36 0.44 0.55 0.64 0.69 120 0.24 0.33 0.41 0.50 0.58 0.63 150 0.21 0.29 0.35 0.43 0.50 0.55 180 0.19 0.26 0.31 0.39 0.45 0.48 360 0.12 0.17 0.20 0.25 0.28 0.30 720 0.08 0.11 0.13 0.16 0.18 0.19 1440 0.05 0.07 0.08 0.10 0.11 0.12 Storm Recurrence Interval Design Standards and Specifications Policy City of Bozeman, March 2004 as Amended Zoning District/Design Storm Requirement Zoning Type Design Rainfall Frequency Open Land 2-year Residential 10-year Commercial 10-year (p. 28, Table I-3) STORMWATER MANAGEMENT MANUAL TABLE 2-5 FREQUENCY FACTORS FOR THE RATIONAL FORMULA Recurrence Interval Adjustment Factor (Years)Cf 2 1.00 5 1.00 10 1.00 25 1.10 50 1.20 100 1.25 * C X Cf should not exceed 1.0 V:17007_02_Storm_Drainage_Plan_030716_SC 11 (04/09/18) SN/jil Appendix C STORMWATER UNIT VOLUMES COST Square Footage of 6" PaveDrain 1 sf 0.09 cf sf $0.00 #57 Stone Base Thickness 30 inches 1.00 cf ton $0.00 Capacity 40% #2 Stone Sub-Base Thickness (Not Required)0 inches 0.00 cf ton $0.00 Capacity 40% Modular Storage System 1 0 0.00 cf cf $0.00 90% TOTAL SYSTEM HEIGHT:36 inches 1.09 cf Total System Capacity 1.09 cf/sf System Efficiency SYSTEM COST:$0 $0.00 cf Cost per Cubic Foot Required System Capacity 0 cf Required PaveDrain Area:0.0 sf 6" PaveDrain 6 inches 0.09 cf/sf #57 Stone Base Thickness 6 inches 0.20 cf/sf Capacity 40% #2 Stone Sub-Base Thickness (Not Required)0 inches 0.00 cf/sf Capacity 40% Modular Storage System Height 1 0 0.00 cf/sf 95% TOTAL SYSTEM HEIGHT:12 inches 0.29 Total cf/sf CAPACITY Determine Storage Capacity of PaveDrain Determine PaveDrain Area Required to Meet Storage Demand CAPACITY ACF Environmental 800-448-3636 www.acfenvironmental.com ACF Environmental 800-448-3636 www.acfenvironmental.com Combined.txt DEPRESSION AREAS ABOVE DRY WELLS - STAGE STORAGE TABLES Stage Storage Table Project: Icon Home Apartments Basin Description: Unit 2A Contour Contour Depth Incremental Cumulative Incremental Cumulative Elevation Area (ft)Volume Volume Volume Volume (sq. ft) Avg. End Avg. End Conic Conic (cu. ft) (cu. ft) (cu. ft) (cu. ft) 4,820.60 2 N/A N/A 0.00 N/A 0.00 4,820.70 33 0.10 1.72 1.72 1.40 1.40 4,820.80 102 0.10 6.75 8.47 6.43 7.83 4,820.90 211 0.10 15.66 24.13 15.34 23.17 4,821.00 347 0.10 27.89 52.03 27.61 50.78 4,821.10 487 0.10 41.71 93.73 41.51 92.29 4,821.20 631 0.10 55.89 149.63 55.74 148.03 4,821.30 777 0.10 70.41 220.04 70.28 218.31 4,821.40 928 0.10 85.25 305.29 85.14 303.45 Stage Storage Table Project: Icon Home Apartments Basin Description: Unit 2B Contour Contour Depth Incremental Cumulative Incremental Cumulative Elevation Area (ft)Volume Volume Volume Volume (sq. ft) Avg. End Avg. End Conic Conic (cu. ft) (cu. ft) (cu. ft) (cu. ft) 4,820.90 18 N/A N/A 0.00 N/A 0.00 4,821.00 76 0.10 4.70 4.70 4.37 4.37 4,821.10 165 0.10 12.01 16.71 11.73 16.10 4,821.20 284 0.10 22.43 39.14 22.16 38.26 4,821.30 435 0.10 35.93 75.07 35.66 73.93 4,821.40 616 0.10 52.52 127.59 52.26 126.18 Stage Storage Tables Project: Icon Home Apartments Basin Description: Unit 2C Contour Contour Depth Incremental Cumulative Incremental Cumulative Elevation Area (ft)Volume Volume Volume Volume (sq. ft) Avg. End Avg. End Conic Conic (cu. ft) (cu. ft) (cu. ft) (cu. ft) 4,821.00 7 N/A N/A 0.00 N/A 0.00 4,821.10 103 0.10 5.48 5.48 4.53 4.53 4,821.20 482 0.10 29.25 34.72 26.92 31.45 Stage Storage Table Project: Icon Home Apartments Basin Description: Unit 4A Contour Contour Depth Incremental Cumulative Incremental Cumulative Elevation Area (ft)Volume Volume Volume Volume (sq. ft) Avg. End Avg. End Conic Conic (cu. ft) (cu. ft) (cu. ft) (cu. ft) 4,822.20 6 N/A N/A 0.00 N/A 0.00 4,822.30 46 0.10 2.58 2.58 2.27 2.27 4,822.40 97 0.10 7.15 9.73 6.99 9.26 4,822.50 154 0.10 12.58 22.31 12.47 21.72 4,822.60 217 0.10 18.58 40.88 18.49 40.21 4,822.70 286 0.10 25.14 66.02 25.06 65.27 Page 1 Combined.txt 4,822.80 360 0.10 32.28 98.30 32.20 97.48 4,822.90 440 0.10 39.98 138.27 39.91 137.39 4,823.00 525 0.10 48.25 186.52 48.18 185.57 4,823.10 616 0.10 57.08 243.60 57.02 242.59 Stage Storage Table Project: Icon Home Apartments Basin Description: Unit 4B Contour Contour Depth Incremental Cumulative Incremental Cumulative Elevation Area (ft)Volume Volume Volume Volume (sq. ft) Avg. End Avg. End Conic Conic (cu. ft) (cu. ft) (cu. ft) (cu. ft) 4,822.50 20 N/A N/A 0.00 N/A 0.00 4,822.60 82 0.10 5.10 5.10 4.74 4.74 4,822.70 187 0.10 13.43 18.52 13.08 17.82 4,822.80 333 0.10 25.97 44.50 25.62 43.44 4,822.90 497 0.10 41.47 85.97 41.20 84.64 4,823.00 663 0.10 57.99 143.96 57.79 142.43 4,823.10 833 0.10 74.82 218.78 74.66 217.09 Stage Storage Table Project: Icon Home Apartments Basin Description: Unit 4C Contour Contour Depth Incremental Cumulative Incremental Cumulative Elevation Area (ft)Volume Volume Volume Volume (sq. ft) Avg. End Avg. End Conic Conic (cu. ft) (cu. ft) (cu. ft) (cu. ft) 4,822.80 28 N/A N/A 0.00 N/A 0.00 4,822.90 97 0.10 6.26 6.26 5.91 5.91 4,823.00 192 0.10 14.47 20.73 14.20 20.12 4,823.10 300 0.10 24.62 45.36 24.42 44.54 Stage Storage Table Project: Icon Home Apartments Basin Description: Unit 4D Contour Contour Depth Incremental Cumulative Incremental Cumulative Elevation Area (ft)Volume Volume Volume Volume (sq. ft) Avg. End Avg. End Conic Conic (cu. ft) (cu. ft) (cu. ft) (cu. ft) 4,823.00 49 N/A N/A 0.00 N/A 0.00 4,823.10 280 0.10 16.44 16.44 14.85 14.85 Stage Storage Table Project: Icon Home Apartments Basin Description: Unit 26A Contour Contour Depth Incremental Cumulative Incremental Cumulative Elevation Area (ft)Volume Volume Volume Volume (sq. ft) Avg. End Avg. End Conic Conic (cu. ft) (cu. ft) (cu. ft) (cu. ft) 4,808.70 0 N/A N/A 0.00 N/A 0.00 4,808.80 8 0.10 0.41 0.41 0.28 0.28 4,808.90 23 0.10 1.59 2.00 1.52 1.80 4,809.00 44 0.10 3.36 5.37 3.31 5.11 4,809.10 69 0.10 5.64 11.01 5.60 10.71 4,809.20 99 0.10 8.43 19.44 8.38 19.09 4,809.30 135 0.10 11.72 31.16 11.68 30.77 Stage Storage Table Page 2 Combined.txt Project: Icon Home Apartments Basin Description: Unit 26B Contour Contour Depth Incremental Cumulative Incremental Cumulative Elevation Area (ft)Volume Volume Volume Volume (sq. ft) Avg. End Avg. End Conic Conic (cu. ft) (cu. ft) (cu. ft) (cu. ft) 4,808.90 8 N/A N/A 0.00 N/A 0.00 4,809.00 34 0.10 2.10 2.10 1.96 1.96 4,809.10 69 0.10 5.15 7.25 5.05 7.00 4,809.20 108 0.10 8.89 16.15 8.82 15.82 4,809.30 151 0.10 12.97 29.12 12.91 28.74 Stage Storage Table Project: Icon Home Apartments Basin Description: Unit 26C Contour Contour Depth Incremental Cumulative Incremental Cumulative Elevation Area (ft)Volume Volume Volume Volume (sq. ft) Avg. End Avg. End Conic Conic (cu. ft) (cu. ft) (cu. ft) (cu. ft) 4,809.10 12 N/A N/A 0.00 N/A 0.00 4,809.20 30 0.10 2.14 2.14 2.08 2.08 4,809.30 51 0.10 4.05 6.20 4.01 6.09 Stage Storage Table Project: Icon Home Apartments Basin Description: Unit 26D Contour Contour Depth Incremental Cumulative Incremental Cumulative Elevation Area (ft)Volume Volume Volume Volume (sq. ft) Avg. End Avg. End Conic Conic (cu. ft) (cu. ft) (cu. ft) (cu. ft) 4,808.90 8 N/A N/A 0.00 N/A 0.00 4,809.00 31 0.10 1.96 1.96 1.83 1.83 4,809.10 65 0.10 4.81 6.77 4.71 6.54 4,809.20 102 0.10 8.31 15.09 8.24 14.79 4,809.30 142 0.10 12.16 27.25 12.11 26.89 Page 3 - F SHEETOFDATE: PROJECT #: DRAWN: CHECKED: THIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS. 4640 TRUEMAN BLVDHILLIARD, OH 430261-800-733-7473 REV DRW CHK DESCRIPTION Tool 5---860-529-8188 |888-892-2694 | WWW.STORMTECH.COM Detention Retention Water Quality ACCEPTABLE FILL MATERIALS: STORMTECH SC-310 CHAMBER SYSTEMSPLEASE NOTE:1. THE LISTED AASHTO DESIGNATIONS ARE FOR GRADATIONS ONLY. THE STONE MUST ALSO BE CLEAN, CRUSHED, ANGULAR. FOR EXAMPLE, A SPECIFICATION FOR #4 STONE WOULD STATE: "CLEAN, CRUSHED,ANGULAR NO. 4 (AASHTO M43) STONE".2. STORMTECH COMPACTION REQUIREMENTS ARE MET FOR 'A' LOCATION MATERIALS WHEN PLACED AND COMPACTED IN 6" (150 mm) (MAX) LIFTS USING TWO FULL COVERAGES WITH A VIBRATORY COMPACTOR.3. WHERE INFILTRATION SURFACES MAY BE COMPROMISED BY COMPACTION, FOR STANDARD DESIGN LOAD CONDITIONS, A FLAT SURFACE MAY BE ACHIEVED BY RAKING OR DRAGGING WITHOUT COMPACTIONEQUIPMENT. FOR SPECIAL LOAD DESIGNS, CONTACT STORMTECH FOR COMPACTION REQUIREMENTS.NOTES:1. SC-310 CHAMBERS SHALL CONFORM TO THE REQUIREMENTS OF ASTM F2418 "STANDARD SPECIFICATION FOR POLYPROPYLENE (PP) CORRUGATED WALL STORMWATER COLLECTION CHAMBERS", OR ASTMF2922"STANDARD SPECIFICATION FOR POLYETHYLENE (PE) CORRUGATED WALL STORMWATER COLLECTION CHAMBERS".2. SC-310 CHAMBERS SHALL BE DESIGNED IN ACCORDANCE WITH ASTM F2787 "STANDARD PRACTICE FOR STRUCTURAL DESIGN OF THERMOPLASTIC CORRUGATED WALL STORMWATER COLLECTIONCHAMBERS".3. "ACCEPTABLE FILL MATERIALS" TABLE ABOVE PROVIDES MATERIAL LOCATIONS, DESCRIPTIONS, GRADATIONS, AND COMPACTION REQUIREMENTS FOR FOUNDATION, EMBEDMENT, AND FILL MATERIALS.4. THE "SITE DESIGN ENGINEER" REFERS TO THE ENGINEER RESPONSIBLE FOR THE DESIGN AND LAYOUT OF THE STORMTECH CHAMBERS FOR THIS PROJECT.5. THE SITE DESIGN ENGINEER IS RESPONSIBLE FOR ASSESSING THE BEARING RESISTANCE (ALLOWABLE BEARING CAPACITY) OF THE SUBGRADE SOILS AND THE DEPTH OF FOUNDATION STONE WITHCONSIDERATION FOR THE RANGE OF EXPECTED SOIL MOISTURE CONDITIONS.6. PERIMETER STONE MUST BE EXTENDED HORIZONTALLY TO THE EXCAVATION WALL FOR BOTH VERTICAL AND SLOPED EXCAVATION WALLS.7. ONCE LAYER 'C' IS PLACED, ANY SOIL/MATERIAL CAN BE PLACED IN LAYER 'D' UP TO THE FINISHED GRADE. MOST PAVEMENT SUBBASE SOILS CAN BE USED TO REPLACE THE MATERIAL REQUIREMENTS OFLAYER 'C' OR 'D' AT THE SITE DESIGN ENGINEER'S DISCRETION.MATERIAL LOCATIONDESCRIPTIONAASHTO MATERIALCLASSIFICATIONSCOMPACTION / DENSITYREQUIREMENTDFINAL FILL: FILL MATERIAL FOR LAYER 'D' STARTSFROM THE TOP OF THE 'C' LAYER TO THE BOTTOMOF FLEXIBLE PAVEMENT OR UNPAVED FINISHEDGRADE ABOVE. NOTE THAT PAVEMENT SUBBASEMAY BE PART OF THE 'D' LAYERANY SOIL/ROCK MATERIALS, NATIVE SOILS, OR PERENGINEER'S PLANS. CHECK PLANS FOR PAVEMENTSUBGRADE REQUIREMENTS.N/APREPARE PER SITE DESIGN ENGINEER'S PLANS.PAVED INSTALLATIONS MAY HAVE STRINGENTMATERIAL AND PREPARATION REQUIREMENTS.CINITIAL FILL: FILL MATERIAL FOR LAYER 'C'STARTS FROM THE TOP OF THE EMBEDMENTSTONE ('B' LAYER) TO 18" (450 mm) ABOVE THETOP OF THE CHAMBER. NOTE THAT PAVEMENTSUBBASE MAY BE A PART OF THE 'C' LAYER.GRANULAR WELL-GRADED SOIL/AGGREGATE MIXTURES, <35%FINES OR PROCESSED AGGREGATE. MOST PAVEMENT SUBBASE MATERIALS CAN BE USED IN LIEUOF THIS LAYER.AASHTO M145¹A-1, A-2-4, A-3ORAASHTO M43¹3, 357, 4, 467, 5, 56, 57, 6, 67, 68, 7, 78, 8, 89,9, 10BEGIN COMPACTIONS AFTER 12" (300 mm) OFMATERIAL OVER THE CHAMBERS IS REACHED.COMPACT ADDITIONAL LAYERS IN 6" (150 mm) MAXLIFTS TO A MIN. 95% PROCTOR DENSITY FORWELL GRADED MATERIAL AND 95% RELATIVEDENSITY FOR PROCESSED AGGREGATEMATERIALS. ROLLER GROSS VEHICLE WEIGHTNOT TO EXCEED 12,000 lbs (53 kN). DYNAMICFORCE NOT TO EXCEED 20,000 lbs (89 kN).BEMBEDMENT STONE: FILL SURROUNDING THECHAMBERS FROM THE FOUNDATION STONE ('A'LAYER) TO THE 'C' LAYER ABOVE.CLEAN, CRUSHED, ANGULAR STONE, NOMINAL SIZEDISTRIBUTION BETWEEN 3/4-2 INCH (20-50 mm)AASHTO M43¹3, 357, 4, 467, 5, 56, 57NO COMPACTION REQUIRED.AFOUNDATION STONE: FILL BELOW CHAMBERSFROM THE SUBGRADE UP TO THE FOOT (BOTTOM)OF THE CHAMBER.CLEAN, CRUSHED, ANGULAR STONE, NOMINAL SIZEDISTRIBUTION BETWEEN 3/4-2 INCH (20-50 mm)AASHTO M43¹3, 357, 4, 467, 5, 56, 57PLATE COMPACT OR ROLL TO ACHIEVE A FLATSURFACE. ² ³18"(450 mm) MIN*8'(2.4 m)MAX6" (150 mm)MINEXCAVATION WALL(CAN BE SLOPED OR VERTICAL)12" (300 mm) MIN12" (300 mm) TYP34" (865 mm)6"(150 mm) MINADS GEOSYNTHETICS 601T NON-WOVEN GEOTEXTILE ALL AROUNDCLEAN CRUSHED, ANGULAR STONE IN A & B LAYERS16"(405 mm)DEPTH OF STONE TO BE DETERMINEDBY DESIGN ENGINEER 6" (150 mm) MIN*TO BOTTOM OF FLEXIBLE PAVEMENT. FOR UNPAVEDINSTALLATIONS WHERE RUTTING FROM VEHICLES MAYOCCUR, INCREASE COVER TO 24" (600 mm).SUBGRADE SOILS(SEE NOTE 5)PAVEMENT LAYER (DESIGNEDBY SITE DESIGN ENGINEER)SC-310END CAPDCBAPERIMETER STONE(SEE NOTE 6)3 5 Icon Home Apartments - Chamber Bozeman, Montana 03/01/2017 SH SHEETOFDATE: PROJECT #: DRAWN: CHECKED: THIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS. 4640 TRUEMAN BLVDHILLIARD, OH 430261-800-733-7473 REV DRW CHK DESCRIPTION Tool 5---860-529-8188 |888-892-2694 | WWW.STORMTECH.COM Detention Retention Water QualityINSPECTION & MAINTENANCESTEP 1) INSPECT ISOLATOR ROW FOR SEDIMENTA. INSPECTION PORTS (IF PRESENT)A.1. REMOVE/OPEN LID ON NYLOPLAST INLINE DRAINA.2. REMOVE AND CLEAN FLEXSTORM FILTER IF INSTALLEDA.3. USING A FLASHLIGHT AND STADIA ROD, MEASURE DEPTH OF SEDIMENT AND RECORD ON MAINTENANCE LOGA.4. LOWER A CAMERA INTO ISOLATOR ROW FOR VISUAL INSPECTION OF SEDIMENT LEVELS (OPTIONAL)A.5. IF SEDIMENT IS AT, OR ABOVE, 3" (80 mm) PROCEED TO STEP 2. IF NOT, PROCEED TO STEP 3.B. ALL ISOLATOR ROWSB.1. REMOVE COVER FROM STRUCTURE AT UPSTREAM END OF ISOLATOR ROWB.2. USING A FLASHLIGHT, INSPECT DOWN THE ISOLATOR ROW THROUGH OUTLET PIPEi) MIRRORS ON POLES OR CAMERAS MAY BE USED TO AVOID A CONFINED SPACE ENTRYii) FOLLOW OSHA REGULATIONS FOR CONFINED SPACE ENTRY IF ENTERING MANHOLEB.3. IF SEDIMENT IS AT, OR ABOVE, 3" (80 mm) PROCEED TO STEP 2. IF NOT, PROCEED TO STEP 3.STEP 2) CLEAN OUT ISOLATOR ROW USING THE JETVAC PROCESSA. A FIXED CULVERT CLEANING NOZZLE WITH REAR FACING SPREAD OF 45" (1.1 m) OR MORE IS PREFERREDB. APPLY MULTIPLE PASSES OF JETVAC UNTIL BACKFLUSH WATER IS CLEANC. VACUUM STRUCTURE SUMP AS REQUIREDSTEP 3) REPLACE ALL COVERS, GRATES, FILTERS, AND LIDS; RECORD OBSERVATIONS AND ACTIONS.STEP 4) INSPECT AND CLEAN BASINS AND MANHOLES UPSTREAM OF THE STORMTECH SYSTEM.NOTES1. INSPECT EVERY 6 MONTHS DURING THE FIRST YEAR OF OPERATION. ADJUST THE INSPECTION INTERVAL BASED ON PREVIOUSOBSERVATIONS OF SEDIMENT ACCUMULATION AND HIGH WATER ELEVATIONS.2. CONDUCT JETTING AND VACTORING ANNUALLY OR WHEN INSPECTION SHOWS THAT MAINTENANCE IS NECESSARY.SC-310 ISOLATOR ROW DETAILNTSSTORMTECH HIGHLY RECOMMENDSFLEXSTORM PURE INSERTS IN ANY UPSTREAMSTRUCTURES WITH OPEN GRATESCOVER ENTIRE ISOLATOR ROW WITH ADSGEOSYNTHETICS 601T NON-WOVEN GEOTEXTILE5' (1.5 m) MIN WIDESC-310 CHAMBERSC-310 END CAPOPTIONAL INSPECTION PORTSUMP DEPTH TBD BYSITE DESIGN ENGINEER(24" [600 mm] MIN RECOMMENDED)12" (300 mm) HDPE ACCESS PIPE REQUIREDUSE FACTORY PRE-FABRICATED END CAPPART #: SC310EPE12BTWO LAYERS OF ADS GEOSYNTHETICS 315WTK WOVENGEOTEXTILE BETWEEN FOUNDATION STONE AND CHAMBERS4' (1.2 m) MIN WIDE CONTINUOUS FABRIC WITHOUT SEAMSCATCH BASINORMANHOLESC-310 6" INSPECTION PORT DETAILNTSSC-310 CHAMBERFLEXSTORM CATCH ITPART# 6212NYFXWITH USE OF OPEN GRATE6" (150 mm) INSERTA TEEPART#06N12ST31IPINSERTA TEE TO BE CENTEREDON CORRUGATION CREST6" (150 mm) ADS N-12HDPE PIPECONCRETE COLLAR12" (300 mm) NYLOPLAST INLINEDRAIN BODY W/SOLID HINGEDCOVER OR GRATEPART# 2712AG06NSOLID COVER: 1299CGCGRATE: 1299CGS18" (450 mm) MIN WIDTHCONCRETE SLAB8" (200 mm) MIN THICKNESSPAVEMENTCONCRETE COLLAR NOT REQUIREDFOR UNPAVED APPLICATION4 5 Icon Home Apartments - Chamber Bozeman, Montana 03/01/2017 SH SHEETOFDATE: PROJECT #: DRAWN: CHECKED: THIS DRAWING HAS BEEN PREPARED BASED ON INFORMATION PROVIDED TO ADS UNDER THE DIRECTION OF THE SITE DESIGN ENGINEER OR OTHER PROJECT REPRESENTATIVE. THE SITE DESIGN ENGINEER SHALL REVIEW THIS DRAWING PRIOR TO CONSTRUCTION. IT IS THE ULTIMATERESPONSIBILITY OF THE SITE DESIGN ENGINEER TO ENSURE THAT THE PRODUCT(S) DEPICTED AND ALL ASSOCIATED DETAILS MEET ALL APPLICABLE LAWS, REGULATIONS, AND PROJECT REQUIREMENTS. 4640 TRUEMAN BLVDHILLIARD, OH 430261-800-733-7473 REV DRW CHK DESCRIPTION Tool 5---860-529-8188 |888-892-2694 | WWW.STORMTECH.COM Detention Retention Water QualityPART #STUB ABCSC310EPE06T / SC310EPE06TPC6" (150 mm) 9.6" (244 mm)5.8" (147 mm)---SC310EPE06B / SC310EPE06BPC---0.5" (13 mm)SC310EPE08T / SC310EPE08TPC8" (200 mm) 11.9" (302 mm)3.5" (89 mm)---SC310EPE08B / SC310EPE08BPC---0.6" (15 mm)SC310EPE10T / SC310EPE10TPC10" (250 mm) 12.7" (323 mm)1.4" (36 mm)---SC310EPE10B / SC310EPE10BPC---0.7" (18 mm)SC310EPE12B12" (300 mm) 13.5" (343 mm)---0.9" (23 mm)ALL STUBS, EXCEPT FOR THE SC310EPE12B ARE PLACED AT BOTTOM OF END CAP SUCH THAT THE OUTSIDE DIAMETER OFTHE STUB IS FLUSH WITH THE BOTTOM OF THE END CAP. FOR ADDITIONAL INFORMATION CONTACT STORMTECH AT1-888-892-2694.* FOR THE SC310EPE12B THE 12" (300 mm) STUB LIES BELOW THE BOTTOM OF THE END CAP APPROXIMATELY 0.25" (6 mm).BACKFILL MATERIAL SHOULD BE REMOVED FROM BELOW THE N-12 STUB SO THAT THE FITTING SITS LEVEL.NOTE: ALL DIMENSIONS ARE NOMINALNOMINAL CHAMBER SPECIFICATIONSSIZE (W X H X INSTALLED LENGTH)34.0" X 16.0" X 85.4" (864 mm X 406 mm X 2169 mm)CHAMBER STORAGE14.7 CUBIC FEET (0.42 m³)MINIMUM INSTALLED STORAGE*31.0 CUBIC FEET (0.88 m³)WEIGHT35.0 lbs.(16.8 kg)*ASSUMES 6" (152 mm) ABOVE, BELOW, AND BETWEEN CHAMBERSSTUBS AT BOTTOM OF END CAP FOR PART NUMBERS ENDING WITH "B"STUBS AT TOP OF END CAP FOR PART NUMBERS ENDING WITH "T"34.0"(864 mm)16.0"(406 mm)90.7" (2304 mm) ACTUAL LENGTH85.4" (2169 mm) INSTALLED LENGTHACCEPTS 4" (100 mm) SCH 40 PVCPIPE FOR INSPECTION PORT. FORPIPE SIZES LARGER THAN 4" (100 mm)UP TO 10" (250 mm) USE INSERTA TEECONNECTION CENTERED ON ACHAMBER CREST CORRUGATIONOVERLAP NEXT CHAMBER HERE(OVER SMALL CORRUGATION)BUILD ROW IN THIS DIRECTIONSTART ENDAABCSC-310 TECHNICAL SPECIFICATIONNTS9.9"(251 mm)45.9"(1166 mm)15.6"(396 mm)INSERTA TEE DETAILNTSINSERTA TEECONNECTIONCONVEYANCE PIPEMATERIAL MAY VARY(PVC, HDPE, ETC.)PLACE ADS GEOSYNTHETICS 315 WOVENGEOTEXTILE (CENTERED ON INSERTA-TEEINLET) OVER BEDDING STONE FOR SCOURPROTECTION AT SIDE INLET CONNECTIONS.GEOTEXTILE MUST EXTEND 6" (150 mm)PAST CHAMBER FOOTINSERTA TEE TO BEINSTALLED, CENTEREDOVER CORRUGATIONSIDE VIEWSECTION A-AAADO NOT INSTALLINSERTA-TEE ATCHAMBER JOINTSNOTE:PART NUMBERS WILL VARY BASED ON INLET PIPE MATERIALS.CONTACT STORMTECH FOR MORE INFORMATION.CHAMBERMAX DIAMETER OFINSERTA TEEHEIGHT FROM BASE OFCHAMBER (X)SC-3106" (150 mm)4" (100 mm)SC-74010" (250 mm)4" (100 mm)DC-78010" (250 mm)4" (100 mm)MC-350012" (300 mm)6" (150 mm)MC-450012" (300 mm)8" (200 mm)INSERTA TEE FITTINGS AVAILABLE FOR SDR 26, SDR 35, SCH 40 IPSGASKETED & SOLVENT WELD, N-12, HP STORM, C-900 OR DUCTILE IRON(X)INTENTIONALLYLEFT BLANK5 5 Icon Home Apartments - Chamber Bozeman, Montana 03/01/2017 SH V:17007_02_Storm_Drainage_Plan_030716_SC 12 (04/09/18) SN/jil Appendix D PIPE CAPACITIES Icon Home Apartments Project #:17007.02 3/7/2018 Standard Single Inlet Qdesign 1.49 cfs Peak Flow n 0.012 RCP Mannings Roughness Coefficient d 12 inches Pipe Diameter S 0.0022 ft/ft Pipe Slope R 0.25 ft2 Hydraulic Radius A 0.7854 ft2 Area Q100 1.81524 cfs Flow Capacity Double Inlet to MHA Qdesign 5.37 cfs Peak Flow n 0.012 RCP Mannings Roughness Coefficient d 15 inches Pipe Diameter S 0.006 ft/ft Pipe Slope R 0.3125 ft2 Hydraulic Radius A 1.22719 ft2 Area Q100 5.43532 cfs Flow Capacity Double Inlet to MHC Qdesign 2.98 cfs Peak Flow n 0.012 RCP Mannings Roughness Coefficient d 15 inches Pipe Diameter S 0.0022 ft/ft Pipe Slope R 0.3125 ft2 Hydraulic Radius A 1.22719 ft2 Area Q100 3.29125 cfs Flow Capacity Double Inlet to MHD Qdesign 1.99 cfs Peak Flow n 0.012 RCP Mannings Roughness Coefficient d 15 inches Pipe Diameter S 0.0015 ft/ft Pipe Slope R 0.3125 ft2 Hydraulic Radius A 1.22719 ft2 Area Q100 2.71766 cfs Flow Capacity Storm Drain Pipe Flow From Inlet to Manhole Icon Home Apartments Project #:17007.02 3/7/2018 MHA to MHB - Watershed 2 Qdesign 5.37 cfs Peak Flow n 0.012 RCP Mannings Roughness Coefficient d 15 inches Pipe Diameter S 0.012 ft/ft Pipe Slope R 0.3125 ft2 Hydraulic Radius A 1.22719 ft2 Area Q100 7.6867 cfs Flow Capacity MHB to MHC - Watershed 2 & 1 Qdesign 10.77 cfs Peak Flow n 0.012 RCP Mannings Roughness Coefficient d 18 inches Pipe Diameter S 0.0112 ft/ft Pipe Slope R 0.375 ft2 Hydraulic Radius A 1.76715 ft2 Area Q100 12.0756 cfs Flow Capacity MHC to Chamber A - Watershed 2 & 1 & 18 & 24 Qdesign 22.9 cfs Peak Flow n 0.012 RCP Mannings Roughness Coefficient d 24 inches Pipe Diameter S 0.009 ft/ft Pipe Slope R 0.5 ft2 Hydraulic Radius A 3.1416 ft2 Area Q100 23.3126 cfs Flow Capacity Storm Drain Pipe Flow To Chamber A Icon Home Apartments Project #:17007.02 3/7/2018 MHD to MHE - Watershed 25 & 26 Qdesign 3.39 cfs Peak Flow n 0.012 RCP Mannings Roughness Coefficient d 15 inches Pipe Diameter S 0.0112 ft/ft Pipe Slope R 0.3125 ft2 Hydraulic Radius A 1.22719 ft2 Area Q100 7.42606 cfs Flow Capacity MHE to Chamber F - Watershed 25 & 26 & 32 Qdesign 8.67 cfs Peak Flow n 0.012 RCP Mannings Roughness Coefficient d 18 inches Pipe Diameter S 0.0128 ft/ft Pipe Slope R 0.375 ft2 Hydraulic Radius A 1.76715 ft2 Area Q100 12.9093 cfs Flow Capacity Inlets to Chamber F - Watershed 39 Qdesign 2.28 cfs Peak Flow n 0.012 RCP Mannings Roughness Coefficient d 12 inches Pipe Diameter S 0.0128 ft/ft Pipe Slope R 0.25 ft2 Hydraulic Radius A 0.7854 ft2 Area Q100 4.37852 cfs Flow Capacity Storm Drain Pipe Flow To Chamber F Icon Home Apartments Project #:17007.02 3/7/2018 MHF to Chamber C - Watershed 23 & 27 Qdesign 5.19 cfs Peak Flow n 0.012 RCP Mannings Roughness Coefficient d 15 inches Pipe Diameter S 0.006 ft/ft Pipe Slope R 0.3125 ft2 Hydraulic Radius A 1.22719 ft2 Area Q100 5.43532 cfs Flow Capacity Storm Drain Pipe Flow To Chamber C Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Discharge Rate, d =0.00 cfs Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 20625 0.473 0.9 1.1 0.99 0.99 0.46875 6910 0.159 0.2 1.1 0.22 0.22 0.03489899 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 27535 0.6321 0.5036 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.50 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 10.72 5.40 5 3.83 1.93 10 2.46 1.24 15 1.89 0.95 20 1.58 0.79 25 1.37 0.69 30 1.22 0.61 35 1.10 0.55 40 1.01 0.51 45 0.94 0.47 50 0.88 0.44 55 0.82 0.42 60 0.78 0.39 75 0.68 0.34 90 0.60 0.30 105 0.55 0.27 120 0.50 0.25 150 0.43 0.22 180 0.39 0.19 360 0.25 0.12 720 0.16 0.08 1440 0.10 ft3 5.40 (ft3/s) 3459.64 0.00 3459.64 4440.19 0.00 4440.19 2100.34 0.00 2100.34 2695.63 0.00 2695.63 1815.08 0.00 1815.08 1966.91 0.00 1966.91 1636.51 0.00 1636.51 1729.89 0.00 1729.89 1414.25 0.00 1414.25 1532.54 0.00 1532.54 1324.40 0.00 1324.40 1370.63 0.00 1370.63 1222.17 0.00 1222.17 1275.11 0.00 1275.11 1101.93 0.00 1101.93 1164.81 0.00 1164.81 952.27 0.00 952.27 1031.93 0.00 1031.93 741.98 0.00 741.98 858.59 0.00 858.59 323.88 0.00 323.88 578.12 0.00 578.12 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.7243 Cwd x Cf =0.80 Runoff Volume Discharge Volume Site Detention = Landscape Totals Impervious RATIONAL METHOD FOR PEAK FLOW CALCULATIONS Post-Project Watershed 1 Surface Type = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Discharge Rate, d =0.00 cfs Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 20969 0.481 0.9 1.1 0.99 0.99 0.476568182 4840 0.111 0.2 1.1 0.22 0.22 0.024444444 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 25809 0.5925 0.5010 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.50 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 10.72 5.37 5 3.83 1.92 10 2.46 1.23 15 1.89 0.95 20 1.58 0.79 25 1.37 0.68 30 1.22 0.61 35 1.10 0.55 40 1.01 0.51 45 0.94 0.47 50 0.88 0.44 55 0.82 0.41 60 0.78 0.39 75 0.68 0.34 90 0.60 0.30 105 0.55 0.27 120 0.50 0.25 150 0.43 0.22 180 0.39 0.19 360 0.25 0.12 720 0.16 0.08 1440 0.10 ft3 5.37 (ft3/s) 3441.53 0.00 3441.53 4416.94 0.00 4416.94 2089.34 0.00 2089.34 2681.51 0.00 2681.51 1805.58 0.00 1805.58 1956.61 0.00 1956.61 1627.94 0.00 1627.94 1720.84 0.00 1720.84 1406.84 0.00 1406.84 1524.52 0.00 1524.52 1317.47 0.00 1317.47 1363.46 0.00 1363.46 1215.77 0.00 1215.77 1268.43 0.00 1268.43 1096.16 0.00 1096.16 1158.71 0.00 1158.71 947.29 0.00 947.29 1026.53 0.00 1026.53 738.09 0.00 738.09 854.09 0.00 854.09 322.19 0.00 322.19 575.10 0.00 575.10 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.7687 Cwd x Cf =0.85 Runoff Volume Discharge Volume Site Detention Landscape Totals = RATIONAL METHOD FOR PEAK FLOW CALCULATIONS Post-Project Watershed 2 Surface Type Impervious = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Discharge Rate, d =0.00 cfs Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 46238 1.061 0.9 1.1 0.99 0.99 1.050863636 15963 0.366 0.2 1.1 0.22 0.22 0.080621212 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 62201 1.4279 1.1315 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =1.13 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min)(in/hr)(ft3/s) 1 10.72 12.13 5 3.83 4.33 10 2.46 2.78 15 1.89 2.14 20 1.58 1.78 25 1.37 1.55 30 1.22 1.38 35 1.10 1.25 40 1.01 1.14 45 0.94 1.06 50 0.88 0.99 55 0.82 0.93 60 0.78 0.88 75 0.68 0.77 90 0.60 0.68 105 0.55 0.62 120 0.50 0.57 150 0.43 0.49 180 0.39 0.44 360 0.25 0.28 720 0.16 0.18 1440 0.10 ft3 12.13 (ft3/s) 7772.33 0.00 7772.33 9975.21 0.00 9975.21 4718.56 0.00 4718.56 6055.92 0.00 6055.92 4077.71 0.00 4077.71 4418.80 0.00 4418.80 3676.53 0.00 3676.53 3886.33 0.00 3886.33 3177.21 0.00 3177.21 3442.97 0.00 3442.97 2975.37 0.00 2975.37 3079.23 0.00 3079.23 2745.70 0.00 2745.70 2864.63 0.00 2864.63 2475.57 0.00 2475.57 2616.83 0.00 2616.83 2139.35 0.00 2139.35 2318.30 0.00 2318.30 1666.91 0.00 1666.91 1928.88 0.00 1928.88 727.63 0.00 727.63 1298.79 0.00 1298.79 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.7204 Cwd x Cf =0.79 Runoff Volume Discharge Volume Site Detention Landscape Totals = RATIONAL METHOD FOR PEAK FLOW CALCULATIONS Post-Project Watershed 18 & 24 Surface Type Impervious = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Discharge Rate, d =0.00 cfs Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 19950 0.458 0.9 1.1 0.99 0.99 0.453409091 7626 0.175 0.2 1.1 0.22 0.22 0.038515152 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 27576 0.6331 0.4919 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.49 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 10.72 5.27 5 3.83 1.88 10 2.46 1.21 15 1.89 0.93 20 1.58 0.78 25 1.37 0.67 30 1.22 0.60 35 1.10 0.54 40 1.01 0.50 45 0.94 0.46 50 0.88 0.43 55 0.82 0.41 60 0.78 0.38 75 0.68 0.33 90 0.60 0.30 105 0.55 0.27 120 0.50 0.25 150 0.43 0.21 180 0.39 0.19 360 0.25 0.12 720 0.16 0.08 1440 0.10 ft3 5.27 (ft3/s) 3379.10 0.00 3379.10 4336.82 0.00 4336.82 2051.44 0.00 2051.44 2632.87 0.00 2632.87 1772.83 0.00 1772.83 1921.12 0.00 1921.12 1598.41 0.00 1598.41 1689.62 0.00 1689.62 1381.32 0.00 1381.32 1496.87 0.00 1496.87 1293.57 0.00 1293.57 1338.73 0.00 1338.73 1193.72 0.00 1193.72 1245.42 0.00 1245.42 1076.28 0.00 1076.28 1137.69 0.00 1137.69 930.10 0.00 930.10 1007.90 0.00 1007.90 724.70 0.00 724.70 838.60 0.00 838.60 316.34 0.00 316.34 564.66 0.00 564.66 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.7064 Cwd x Cf =0.78 Runoff Volume Discharge Volume Site Detention Landscape Totals = RATIONAL METHOD FOR PEAK FLOW CALCULATIONS Post-Project Watershed 24 Surface Type Impervious = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Discharge Rate, d =0.00 cfs Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 12396 0.285 0.9 1.1 0.99 0.99 0.281727273 6888 0.158 0.2 1.1 0.22 0.22 0.034787879 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 19284 0.4427 0.3165 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.32 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 10.72 3.39 5 3.83 1.21 10 2.46 0.78 15 1.89 0.60 20 1.58 0.50 25 1.37 0.43 30 1.22 0.38 35 1.10 0.35 40 1.01 0.32 45 0.94 0.30 50 0.88 0.28 55 0.82 0.26 60 0.78 0.25 75 0.68 0.21 90 0.60 0.19 105 0.55 0.17 120 0.50 0.16 150 0.43 0.14 180 0.39 0.12 360 0.25 0.08 720 0.16 0.05 1440 0.10 ft3 3.39 (ft3/s) 2174.19 0.00 2174.19 2790.41 0.00 2790.41 1319.94 0.00 1319.94 1694.05 0.00 1694.05 1140.68 0.00 1140.68 1236.09 0.00 1236.09 1028.45 0.00 1028.45 1087.14 0.00 1087.14 888.77 0.00 888.77 963.12 0.00 963.12 832.31 0.00 832.31 861.37 0.00 861.37 768.07 0.00 768.07 801.33 0.00 801.33 692.50 0.00 692.50 732.02 0.00 732.02 598.45 0.00 598.45 648.51 0.00 648.51 466.29 0.00 466.29 539.57 0.00 539.57 203.54 0.00 203.54 363.32 0.00 363.32 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.6500 Cwd x Cf =0.71 Runoff Volume Discharge Volume Site Detention Landscape Totals = RATIONAL METHOD FOR PEAK FLOW CALCULATIONS Post-Project Watershed 25 & 26 Surface Type Impervious = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Discharge Rate, d =0.00 cfs Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 19415 0.446 0.9 1.1 0.99 0.99 0.44125 10127 0.232 0.2 1.1 0.22 0.22 0.051146465 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 29542 0.6782 0.4924 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.49 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 10.72 5.28 5 3.83 1.88 10 2.46 1.21 15 1.89 0.93 20 1.58 0.78 25 1.37 0.67 30 1.22 0.60 35 1.10 0.54 40 1.01 0.50 45 0.94 0.46 50 0.88 0.43 55 0.82 0.41 60 0.78 0.38 75 0.68 0.33 90 0.60 0.30 105 0.55 0.27 120 0.50 0.25 150 0.43 0.21 180 0.39 0.19 360 0.25 0.12 720 0.16 0.08 1440 0.10 ft3 5.28 (ft3/s) 3382.34 0.00 3382.34 4340.98 0.00 4340.98 2053.41 0.00 2053.41 2635.40 0.00 2635.40 1774.53 0.00 1774.53 1922.96 0.00 1922.96 1599.94 0.00 1599.94 1691.24 0.00 1691.24 1382.65 0.00 1382.65 1498.30 0.00 1498.30 1294.81 0.00 1294.81 1340.01 0.00 1340.01 1194.87 0.00 1194.87 1246.62 0.00 1246.62 1077.31 0.00 1077.31 1138.79 0.00 1138.79 931.00 0.00 931.00 1008.87 0.00 1008.87 725.40 0.00 725.40 839.40 0.00 839.40 316.65 0.00 316.65 565.21 0.00 565.21 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.6600 Cwd x Cf =0.73 Runoff Volume Discharge Volume Site Detention Landscape Totals = RATIONAL METHOD FOR PEAK FLOW CALCULATIONS Post-Project Watershed 32 Surface Type Impervious = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Discharge Rate, d =0.00 cfs Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 7088 0.163 0.9 1.1 0.99 0.99 0.161090909 10141 0.233 0.2 1.1 0.22 0.22 0.051217172 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 17229 0.3955 0.2123 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.21 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 10.72 2.28 5 3.83 0.81 10 2.46 0.52 15 1.89 0.40 20 1.58 0.33 25 1.37 0.29 30 1.22 0.26 35 1.10 0.23 40 1.01 0.21 45 0.94 0.20 50 0.88 0.19 55 0.82 0.18 60 0.78 0.17 75 0.68 0.14 90 0.60 0.13 105 0.55 0.12 120 0.50 0.11 150 0.43 0.09 180 0.39 0.08 360 0.25 0.05 720 0.16 0.03 1440 0.10 ft3 2.28 (ft3/s) 1458.37 0.00 1458.37 1871.71 0.00 1871.71 885.38 0.00 885.38 1136.31 0.00 1136.31 765.13 0.00 765.13 829.13 0.00 829.13 689.85 0.00 689.85 729.22 0.00 729.22 596.16 0.00 596.16 646.03 0.00 646.03 558.29 0.00 558.29 577.78 0.00 577.78 515.19 0.00 515.19 537.51 0.00 537.51 464.51 0.00 464.51 491.01 0.00 491.01 401.42 0.00 401.42 435.00 0.00 435.00 312.77 0.00 312.77 361.93 0.00 361.93 136.53 0.00 136.53 243.70 0.00 243.70 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.4880 Cwd x Cf =0.54 Runoff Volume Discharge Volume Site Detention Landscape Totals = RATIONAL METHOD FOR PEAK FLOW CALCULATIONS Post-Project Watershed 39 Surface Type Impervious = Project: Icon Home Apartments Project #: 17007.02 Date: 7/25/2017 Design Storm Frequency =25 years Discharge Rate, d =0.00 cfs Input values for runoff coefficients from appropriate tables. Area Area Runoff Coefficient Frequency Factor Calculation Value A A/(43560 ft2/acre)C Cf C x Cf C' C' x A (ft2)(Acres)=(C x Cf) < or = 1 (Acres) 19442 0.446 0.9 1.1 0.99 0.99 0.441863636 8443 0.194 0.2 1.1 0.22 0.22 0.042641414 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 0 1.1 0.00 0.00 0 27885 0.6402 0.4845 Weighted Runoff Coefficient, Cwd SCjAj SAj Cwd x Cf x SAj =0.48 Where Cj is the adjusted runoff coefficient for surface type j and Aj is the area of surface type j Rainfall Rainfall Peak Flow Duration, t Intensity, i = Cwd x SAj x i (min) (in/hr)(ft3/s) 1 10.72 5.19 5 3.83 1.85 10 2.46 1.19 15 1.89 0.92 20 1.58 0.76 25 1.37 0.66 30 1.22 0.59 35 1.10 0.53 40 1.01 0.49 45 0.94 0.45 50 0.88 0.42 55 0.82 0.40 60 0.78 0.38 75 0.68 0.33 90 0.60 0.29 105 0.55 0.26 120 0.50 0.24 150 0.43 0.21 180 0.39 0.19 360 0.25 0.12 720 0.16 0.08 1440 0.10 ft3 5.19 (ft3/s) 3328.13 0.00 3328.13 4271.41 0.00 4271.41 2020.50 0.00 2020.50 2593.16 0.00 2593.16 1746.09 0.00 1746.09 1892.14 0.00 1892.14 1574.30 0.00 1574.30 1664.14 0.00 1664.14 1360.49 0.00 1360.49 1474.29 0.00 1474.29 1274.06 0.00 1274.06 1318.53 0.00 1318.53 1175.72 0.00 1175.72 1226.64 0.00 1226.64 1060.05 0.00 1060.05 1120.54 0.00 1120.54 916.08 0.00 916.08 992.70 0.00 992.70 713.77 0.00 713.77 825.95 0.00 825.95 311.57 0.00 311.57 556.15 0.00 556.15 = Cwd x SAj x i x t = d x t = Runoff Volume - Discharge Volume (ft3)(ft3)(ft3) =0.6881 Cwd x Cf =0.76 Runoff Volume Discharge Volume Site Detention Landscape Totals = RATIONAL METHOD FOR PEAK FLOW CALCULATIONS Post-Project Watershed 23 & 27 Surface Type Impervious = V:17007_02_Storm_Drainage_Plan_030716_SC 13 (04/09/18) SN/jil Appendix E INFILTRATION DATA Encased Falling Head Test Results On Third Trial Time (min)Depth (in)in/hr Time (min)Depth (in)in/hr Time (min)Depth (in)in/hr 0 24 0 24 0 24 0.18 12 4000.00 0.3 20 800.00 0.35 20 685.71 0.22 11 1500.00 0.45 19 400.00 0.38 19 2000.00 0.4 10 333.33 0.53 18 750.00 0.41 18 2000.00 1.06 9 90.91 1.04 17 117.65 0.43 17 3000.00 1.5 8 136.36 1.12 16 750.00 0.47 16 1500.00 2.41 7 65.93 1.2 15 750.00 0.5 15 2000.00 3.4 6 60.61 1.3 14 600.00 0.53 14 2000.00 5 5 37.50 1.43 13 461.54 0.57 13 1500.00 6.22 4 49.18 1.56 12 461.54 1 12 139.53 8.04 3 32.97 2.1 11 111.11 1.07 11 857.14 10.28 2 26.79 2.28 10 333.33 1.14 10 857.14 12 1 34.88 2.48 9 300.00 1.2 9 1000.00 14.07 0 28.99 3.05 8 105.26 1.27 8 857.14 3.25 7 300.00 1.38 7 545.45 Average 102.35 3.49 6 250.00 2.19 6 74.07 4.17 5 88.24 2.56 5 162.16 4.5 4 181.82 3.18 4 96.77 5.36 3 69.77 3.58 3 150.00 6.22 2 69.77 5.01 2 41.96 7.07 1 70.59 5.58 1 105.26 8.22 0 52.17 6.57 0 60.61 Average 175.18 Average 219.18 Southwest Corner Northwest Corner Northeast Corner V:17007_02_Storm_Drainage_Plan_030716_SC 14 (04/09/18) SN/jil Appendix F MAINTENANCE PLAN July 25, 2017 Updated April 9, 2018 Project No. 17007.02 STORM DRAINAGE FACILITY MAINTENANCE PLAN FOR ICON APARTMENT HOMES AT FERGUSON FARM BOZEMAN, MONTANA OVERVIEW NARRATIVE The purpose of this maintenance plan is to outline the necessary details related to ownership, responsibility and cleaning schedule for the storm drainage facilities for the Icon Apartment Homes at Ferguson Farm Master Site Plan. This plan has been completed in accordance with The City of Bozeman Design Standards and Specifications Policy, dated March 2004. The site stormwater improvements have been designed with the intent to meet the current City of Bozeman drainage regulations for the entire site to the extent feasible. Specific site information and criteria are described below: I.Ownership of Facilities Apartment Community Bozeman Apartment Group, LLC will own all stormwater facilities, including the ADS StormTech chamber systems, pervious pavers, dry wells, inlets and storm drain piping within Lot 3A of Minor Subdivision 365 that is not within the public access easements. Additionally, Bozeman Apartment Group, LLC will own all retention/detention systems within the public access easements for Palisade Drive and South Stafford Avenue. Public Access Easements The street public access easements for Palisade Drive and South Stafford Avenue will include ADS StormTech chamber infiltration systems, inlets, and storm drain piping. The City of Bozeman will own all the stormwater facilities within their easements except for the ADS StormTech chamber infiltration systems. V:17007.02_SD Maintenance Plan 2 (04/09/18) SH/LW II.Inspection Thresholds for Cleaning ADS Chamber System If the average depth of sediment exceeds 3 inches, clean ADS Chamber System. Refer to Isolator Row Maintenance Plan attached. Pervious Pavers If the average depth of sediment exceeds 2 inches, clean paver system. Refer to PaveDrain specifications attached. Dry Wells If sediment in sump exceeds 5 inches or grate is more than 25% clogged with debris, clean grate and/or structure. Storm Drain Inlets and Manholes If sediment in sump exceeds 5 inches or grate is more than 25% clogged with debris, clean grate and/or structure. Storm Drain Piping If sediment in sump exceeds 2 inches, clean pipe. III.Cleaning ADS Chamber System To clean ADS Chamber Systems, use the JetVac process outlined in the Isolator Row Inspection/Maintenance plan attached. PaveDrain To clean PaveDrain pavers, use an approved vacuum as outlined in the PaveDrain specifications attached. Nearby Owner of Vacuum Head David – Rocky Mountain Super Vac 73 Morning Glory Lane Kalispell, MT 59901 406-257-4639 Manholes, Inlets, Dry Wells To clean grate of structure, remove and dispose of debris clogging the grate. To clean structure, use catch basin vacuum to remove sediment and debris. Pipes To clean pipes, flush pipe at inlet structure and ensure that debris is captured at outlet structure and is removed. V:17007.02_SD Maintenance Plan 3 (04/09/18) SH/LW IV.Schedule ADS Chamber System Inspection: Every 6 months Vacuum Manholes/Chambers: Every 5 years or as needed based on inspection Note: Refer to Isolator Row Maintenance Plan attached. Pervious Pavers Inspection: Every 6 months Vacuum pavers every 5-7 years or as needed based on inspection. Note: PaveDrain specifications attached. Dry Wells Inspection: Every 6 months Vacuum Drywells: Every 5 years or as needed based on inspection Storm Drain Inlets and Manholes Inspection: Every 6 months Vacuum Inlets/Manholes: Every 5 years or as needed based on inspection Storm Drain Piping Inspection: Inspect inverts and outlet inverts every 6 months Flush pipes every 5 years or as needed based on inspection and condition of inlet or manhole. V.Responsible Party City of Bozeman The City of Bozeman will be responsible for the inspection and maintenance of the stormwater inlets, manholes and pipes within the public access easements for Palisade Drive and South Stafford Avenue. Bozeman Apartment Group, LLC Bozeman Apartment Group, LLC will be responsible for all stormwater facilities located within Lot 3A of Minor Subdivision 365 and will be responsible for maintaining any ADS StormTech Chambers within the public access easements. This includes the chamber system designed to retain the deficient volume from the Ferguson Farm subdivision to the south. PERMEABLE ARTICULATING CONCRETE BLOCK (P-ACB) SPECIFICATION FOR PARKING LOTS, DRIVEWAYS, ALLEYS AND ROADWAYS PART 1: GENERAL A.Definitions Contract Documents – the Contract Documents establish the rights and obligations ofthe parties and include the Agreement, Addenda (which pertain to the ContractDocuments), CONTRACTOR’s Bid (including documentation accompanying the Bidand any post Bid documentation submitted prior to the Notice of Award) when attached as an exhibit to the Agreement, the Notice to Proceed, the Bonds, the General conditions, the Supplementary Conditions, the Specifications and the Drawings as thesame are more specifically identified in the Agreement, together with all WrittenAmendments, Change Orders, Work Change Directives, Field Orders, andENGINEER’s written interpretations and clarifications issued on or after the Effective Date of the Agreement. Approved Shop Drawings and the reports of subsurface andphysical conditions are not Contract Documents. Only printed hard copies of the itemslisted in this paragraph are Contract Documents. Files in electronic media format, oftext, data, graphics, and the like that may be furnished by OWNER to CONTRACTOR are not Contract Documents. CONTRACTOR – The individual or entity with whom OWNER has entered into theAgreement. Drawings – That part of the Contract Documents prepared or approved by the ENGINEER which graphically shows the scope, extent, and character of the Work to be performed by the CONTRACTOR. Shop Drawings and other CONTRACTOR submittals are not Drawings as so defined. ENGINEER- The individual or entity named as such in the Agreement. OWNER – The individual, entity, public body, or authority with whom the CONTRACTOR has entered into the Agreement and for whom the Work is to be performed. Project – The total construction of which the Work to be performed under the Contract Documents may be the whole, or part as may be indicated elsewhere in the Contract Documents. Resident Project Representative – The authorized representative of the ENGINEER who may be assigned to the Site or any part thereof. Samples – Physical examples of materials, equipment, or workmanship that are representative of some portion of the Work and which establish the standards by which such portions of the Work will be judged. Shop Drawings – All drawings, diagrams, illustrations, schedules, and other data or information which are specifically prepared or assembled for the CONTRACTOR and submitted by the CONTRACTOR to illustrate some portion of the Work. Site – Lands or areas indicated in the Contract Documents as being furnished by the OWNER upon which the Work is to be performeed, including the rights-of-way and easements for access thereto, and such other lands furnished by OWNER which are designated for the use of the CONTRACTOR. Specifications – That part of the Contract Documents consisting of written technical descriptions of materials, equipment, systems, standards, and workmanship applied to the Work and certain adminstrative details applicable there to. Subcontractor – An individual or entity having a direct contract with CONTRACTOR or with any other Subcontractor for the performance of a part of the Work at the Site. Supplier – A manufaturer, fabricator, supplier, distributor, material man, or vendor having a direct contract with CONTRACTOR or with any Subcontractor to furnish materials or equipment to be incorporated in the Work by the CONTRACTOR or Subcontractor. Work- The entire completed construction of the various separately identifiable parts thereof required to be provided under the Contract Documents. Work includes and is the result of performing or providing all labor, services and documentation necessary to produce such construction and furnishing, installing, and incorporating all materials and equipment into such construction, as required by the Contract Documents. B.Scope of Work The contractor shall furnish all labor, materials, equipment, and incidentals required andperform all operations in connection with the installation of the Permeable Articulating Concrete Block (P-ACB) in accordance with the lines, grades, design and dimensionsshown on the Contract Drawings and as specified herein. C.Submittal The contractor shall submit to the engineer all manufacturer's performance research results and calculations in support of the permeable articulating concrete blocksP-ACB system and geotextile proposed for use. The contractor shall furnish to the engineer all manufacturer's specifications, literature, and installation drawings of the P-ACB. D.Preconstruction Conference Within 2 weeks prior to the installation of the P-ACB, a conference attended byCONTRACTOR, ENGINEER, Supplier, and others as appropriate will be held to establish a working understanding among the parties as to the Work and to discuss theschedules, procedures for handling Shop Drawings and other submittals, processingApplications for Payment, and maintaining required records. PART 2: PRODUCTS A.GENERAL Permeable Articulating Concrete Blocks (P-ACB) shall be premanufactured ofindividual concrete blocks with specific stormwater runoff and storage capacities. Blocks shall be hand-placed or mechanically installed with the use of a clamping or suction lifting device. Individual blocks in the P-ACB shall be staggered, beveled, and interlocked forenhanced stability. The blocks shall be constructed of closed cell blocks with an arched storage chamber for additional stormwater runoff as shown on the contract drawings. Each row of blocks shall be laterally offset by one-half block width from the adjacentrow so that any given block is interlocked to four other blocks (two in the row above andtwo in the row below). Six adjacent blocks shall also surround each block. Each block shall incorporate interlocking surfaces that prevent lateral displacement of the blocks. The interlocking surfaces shall not protrude beyond the perimeter of theblocks to such an extent that they reduce the flexibility or articulating capability of thesystem. Backfilling of the joints between the P-ACB with rock chips or sand is notrequired and shall not be done or included in the Work. Infiltration Performance: The P-ACB will only be accepted when accompanied bydocumented third party infiltration performance characteristics based on ASTMC1701/C1701M-09, or C1781. The infiltration rate shall be no less than 1,000 inches perhour on an outdoor working surface, with typical base material utilized for the test. Structural Performance: The design of the P-ACB shall be capable of supportingAASHTO H-25 and HS-25 truck loading. The blocks shall be analyzed as unreinforcedconcrete arches supporting a uniform truck tire load with impact per AASHTOstandards. The subgrade soil, geosynthetic and base preperation for the P-ACB shall be properly designed by a Registered Professional Engineer and inspected by the ENGINEER or the Resident Project Representative during and following theinstallation of the Work. B.Cellular Concrete Blocks Materials Cementitious Materials - Materials shall conform to the following applicableASTM specifications: Portland Cements - Specification C 150, for Portland Cement. Blended Cements - Specification C 595, for Blended Hydraulic Cements. Hydrated Lime Types - Specification C 207, for Hydrated Lime Types. Pozzolans - Specifications C 618, for Fly Ash and Raw or Calcinated NaturalPozzolans for use in Portland Cement Concrete. Aggregates shall conform to the following ASTM specifications. Normal Weight - Specification C 33, for Concrete Aggregates. Visual Inspection All units shall be sound and free of defects that would interfere with the proper placing of the unit or impair the strength or permanence of the construction. Surface cracks incidental to the usual methods of manufacture, or surface chipping resulting from customary methods of handling in shipment and delivery, shall not be deemed grounds for rejection. Cracks exceeding 0.25 inches in width and/or 1.0 inch in depth shall be deemed grounds for rejection. Physical Requirements At the time of delivery to the work site, the units shall conform to the physical requirements prescribed in Table 1, Physical Characteristics. TABLE 1: PHYSICAL CHARACTERISTICS Item Description Values Dimensions Length x Width x Height 12” x 12” x 5.65” (+/- 1/8”) Compressive Strength ASTM D-6684 / C-140 Avg. of Three: 4,000 psi min. Individual units: 3,500 psi min. Block Weight Arched Block: 45-50 lbs/sf Solid Block: 55-60 lbs/sf Loading Capabilities Truck Load Traffic Rating AASHTO H-20, HS-20, HS-25 Joint Filler Between Blocks Material Used NONE Required Percent Open Space Surface: 7% Storage: 20% Water Absorption (%) Density (lbs/cf) ASTM D-6684 Table 1 / ASTM C-140 9.1% Avg. of Three, 11.7% Individual 130 Avg of Three, 125 Individual Storage Capacity Above Aggregate Within Arch 0.0833 cf/block Post-Installation, Verified Surface Infiltration Rate ASTM C1701/C1701M-09 ASTM C1781 Ave of three tests: 1,000 inches/hour/sf (MIN. 3 tests) Sampling and Testing The OWNER, ENGINEER or their authorized representative shall be accorded proper access to the manufacturer to inspect and obtain samples of the Permeable Articulating Concrete Blocks at the place of manufacture from lots ready for delivery. Expense of Tests Additional testing and associated costs, other than that provided by the manufacturer, shall be borne by the OWNER. Manufacturer The Permeable Articulating Concrete Blocks shall be PaveDrain® or pre-approved equal, as represented or distributed by: LOCALY NATIONAL ACF West, Inc. PaveDrain, LLC PH. (800) 878-511500-597-2180 PH. (888) 575-5339info@acfwest.com info@pavedrain.com http://www.acfwest.com www.pavedrain.com "Or-Equal" Items: If in ENGINEER's sole discretion an item of material or equipment proposed by CONTRACTOR is functionally equal to that named and sufficiently similar so that no change in related Work will be required, it may be considered by ENGINEER as an "or-equal" item, in which case review and approval of the proposed item may, in ENGINEER's sole discretion, be accomplished without compliance with some or all of the requirements for approval of proposed substitute items. A proposed item of material or equipment will be considered functionally equal to an item so named if: a.in the exercise of reasonable judgment ENGINEER determines that: (i) it is at least equal in quality, durability, appearance, strength, and design characteristics; (ii) it will reliably perform at least equally well the function imposed by the design concept of the completed Project as a functioning whole, and; b.CONTRACTOR certifies that: (i) there is no increase in cost to the OWNER; and(ii) it will conform substantially, even with deviations, to the detailed requirements ofthe item named in the Contract Documents. PART 3: FOUNDATION PREPARATION AND BLOCK INSTALLATION A.Foundation and Preparation General. Areas on which permeable articulating concrete blocks are to be placed shall be constructed to the lines and grades shown on the Drawings and to the tolerances specified in the Contract Documents. Any proposed changes shall bereviewed and approved by the ENGINEER. References.1.Oregon DOT – 2015 Standard Specifications for Construction.2.Washington DOT – 2016 Standard Specifications for Road, Bridge & MunicipalConstruction.3.Idaho Transportation Dept – 2012 Standard Specification for Highway Construction 4.Utah DOT – 2017 Standards and Specifications 5. Nevada DOT – 2014 Standard Specifications for Road and Bridge Construction.6. Montana DOT – 2014 Standard Specifications for Road and Bridge Construction. Subgrade. Unless required on the Drawings, compaction of underlying subgrade soil shall be avoided or minimized in order to encourage infiltration of stormwater. A Geotechnical Engineer should be consulted to determine the CBR values of the subgrade prior to the installation of the subbase materials and geotextile stabilizing fabrics and grids. Geotextile Separator or Geogrid Stabilization. Monofilament or multifilament geotextile, that include Mirafi RS380i or its equivalent, or other geotextile material as shown on the Drawings shall be installed on the bottom and sides of the excavation to prevent in – situ soil contamination of the clean aggregate subbase. A geogrid may be required for sub base stabilization, but is not recommended on the sides of the aggregate sub base to separate the in-situ soils from the clean sub base aggregate. Aggregate Subbase. If more than 6” of base aggregate is required, as shown on the Drawings,, only the top 4-6” shall be AASHTO #57 aggregate. The aggregate shall be clean, angular on all sides with no fines.As shown on the Drawings, this is the leveling course directly beneath the P-ACB blocks. Additional aggregate depth shall consist of either AASHTO #2 or #3 clean, angular on all sides, aggregate, or as shown on Drawings. Crushed Aggregate Base Course: Follow State Specifications Compaction: Standard compaction. 95 percent maximum density determined by Modified Proctor. Allow ENGINEER to inspect prepared base course and to witness proof roll test by a fully loaded dump truck. Reconstruct where deflection is greater than ½ inch. Allowable deviation from design grade: ½ inch. The base course shall be firm and non-yielding, compacted until it does not creep or weave in front of the roller or compacting vehicle. The aggregate bedding layer shall be compacted to a smooth plane surface to ensure intimate and positive contact is achieved between the legs of the permeable articulating concrete blocks and the compacted aggregate subbase layer and the Geogrid Separator. AASHTO #2 or #3 subbase aggregate shall be compacted in 6-8” lifts with a roller-compactor. The AASHTO #57 aggregate leveling subbase shall be rolled and then compacted with a minimum 10,000 psi plate compactor in both the perpendicular and parallel directions in the area of coverage.The CONTRACTOR shall compact a 2” layer of the AASHTO #57 Aggregate into AASHTO #2 or #3 aggregate. Geogrid Separator. Install Naue Secugrid 20/20, (or equal) geogrid separator shall be directly on top of the compacted leveling course. The geogrid seperator may be installed prior to the compaction of the leveling course. This will create a “snow shoe” effect and minimize damage from foot traffic prior to placement of the P-ACB. Inspection. Immediately prior to placing the P-ACB the prepared area shall be inspected by the ENGINEER or Resident Project Representative, the OWNER’s representative, and or by the manufacturer's representative. No blocks shall be placed thereon until that area has been approved by the ENGINEER. B.Placement of Permeable Articulating Concrete Blocks General. Permeable articulating concrete blocks shall be constructed within the specified lines and grades shown on the Drawings. Placement. The P-ACB shall be placed on the geogrid separator so as to produce a smooth plane surface. No individual block within the plane of placed articulating concrete mats shall protrude more than one-quarter of an inch unless otherwise specified by the ENGINEER. Consultation. The Supplier will provide design and construction advice during the design and installation phases of the project. The Supplier will not supervise, direct, control, or have authority over or be responsible for CONTRACTOR's means, methods, techniques, sequences, or procedures of construction, or the safety precautions and programs incident thereto, or for any failure of CONTRACTOR to comply with Laws and Regulations applicable to the performance of the Work. Finishing. The joints between the P-ACB shall not be backfilled with smaller aggregates or sand in order to function properly. The joints shall be left open. This includes following maintenance of the P-ACB. If the joints are filled with smaller aggregates or sand, the CONTRACTOR shall be responsible for the removal of the material and perform infiltration tests to assure that the P-ACB meets the minimum infiltration tests described in this specification. Post Installation Certification. Upon completion of the P-ACB installation, the surface infiltration rate of the pavement shall be verified by ASTM C1701M-09 or ASTM C1781 to confirm the required infiltration rate of the pavement (per Table 1). If the system fails to perform as required in section Table 1 of this spec, it shall be removed and replaced at the supplier’s cost. C.Maintenance of Permeable Articulating Concrete Blocks General. The maintainabilty of the permeable articulating concrete blocks shall be based on a maintenance study of at least 24 months conducted by an independent or third party representation. -The study shall include multiple pre and post testing documentations in multiple locations of infiltration rates according to ASTM C1701 or a modified versionof ASTM C1701 where the infiltration rate is recorded without a head pressure.-Subsurface aggregate performance of pre and post testing shall also bedocumented over a 24 month period. -The study shall show that following proper maintenance the original performance of the P-ACB can effectively be restored to at least 90% of itsoriginal performance. Inspection & Maintenance. The manufacturer’s representative of the P-ACB shall provide a minimum 36 month maintenance program; including a visual inspection report with photos and a recommended cleaning schedule with a Vacuum truck such as the Elgin® Whirlwind® or Megawind® or with the PaveDrain® Vac Head and associated combination sanitation vac truck. The visual inspection and recommended cleaning schedule shall be included with the price of the system. Maintenance utilizing a combination sanitation vaccum truck with the PaveDrain vac head will be quoted and supplied by others based on the maintenance program. Maintenance shall be required when either of the following are reached: a.The surface infiltration rates of more than 75% of the surface area fall below10% of the rate required in Table 1. b.Surface ponding remains for 24 hours in an area larger than 10 square feet. Isolator®Row O&M Manual StormTech®Chamber System for Stormwater Management Save Valuable Land and Protect Water Resources Detention • Retention • Water Quality A division of 1.1 INTRODUCTION An important component of any Stormwater Pollution Prevention Plan is inspection and maintenance. The StormTech Isolator Row is a patented technique to inexpensively enhance Total Suspended Solids (TSS) removal and provide easy access for inspection and maintenance. 1.2 THE ISOLATOR ROW The Isolator Row is a row of StormTech chambers, either SC-310, SC-310-3, SC-740, DC-780, MC-3500 or MC- 4500 models, that is surrounded with filter fabric and con- nected to a closely located manhole for easy access. The fabric-wrapped chambers pro vide for settling and filtra- tion of sediment as storm water rises in the Isolator Row and ultimately passes through the filter fabric. The open bottom chambers and perforated sidewalls (SC-310, SC- 310-3 and SC-740 models) allow storm water to flow both vertically and horizon tally out of the chambers. Sediments are cap tured in the Isolator Row protecting the storage areas of the adjacent stone and chambers from sediment accumulation. Two different fabrics are used for the Isolator Row. A woven geotextile fabric is placed between the stone and the Isolator Row chambers. The tough geo textile provides a media for storm water filtration and provides a durable surface for maintenance operations. It is also designed to prevent scour of the underlying stone and remain intact during high pressure jetting. A non-woven fabric is placed over the chambers to provide a filter media for flows passing through the perforations in the sidewall of the chamber. The non-woven fabric is not required over the DC-780, MC-3500 or MC-4500 models as these chambers do not have perforated side walls. 2 Call StormTech at 888.892.2694 or visit our website at www.stormtech.com for technical and product information. 1.0 The Isolator®Row The Isolator Row is typically designed to capture the “first flush” and offers the versatility to be sized on a vol- ume basis or flow rate basis. An upstream manhole not only provides access to the Isolator Row but typically includes a high flow weir such that storm water flowrates or volumes that exceed the capacity of the Isolator Row overtop the over flow weir and discharge through a manifold to the other chambers. The Isolator Row may also be part of a treatment train. By treating storm water prior to entry into the chamber system, the service life can be extended and pollutants such as hydrocarbons can be captured. Pre-treatment best management practices can be as simple as deep sump catch basins, oil-water separators or can be inno- vative storm water treatment devices. The design of the treatment train and selection of pretreatment devices by the design engineer is often driven by regulatory requirements. Whether pretreatment is used or not, the Isolator Row is recommended by StormTech as an effective means to minimize maintenance requirements and maintenance costs. Note: See the StormTech Design Manual for detailed information on designing inlets for a StormTech system, including the Isolator Row. ECCENTRIC HEADER MANHOLE WITH OVERFLOW WEIR STORMTECH ISOLATOR ROW OPTIONAL PRE-TREATMENT OPTIONAL ACCESS STORMTECH CHAMBERS StormTech Isolator Row with Overflow Spillway (not to scale) Looking down the Isolator Row from the manhole opening, woven geotextile is shown between the chamber and stone base. 2.0 Isolator Row Inspection/Maintenance Call StormTech at 888.892.2694 or visit our website at www.stormtech.com for technical and product information. 3 Maintenance is accomplished with the JetVac process. The JetVac process utilizes a high pressure water noz- zle to propel itself down the Isolator Row while scouring and suspending sediments. As the nozzle is retrieved, the captured pollutants are flushed back into the man- hole for vacuuming. Most sewer and pipe maintenance companies have vacuum/JetVac combination vehicles. Selection of an appropriate JetVac nozzle will improve maintenance efficiency. Fixed nozzles designed for cul- verts or large diameter pipe cleaning are preferable. Rear facing jets with an effective spread of at least 45” are best. Most JetVac reels have 400 feet of hose allow- ing maintenance of an Isolator Row up to 50 chambers long. The JetVac process shall only be performed onStormTech Isolator Rows that have AASHTO class 1woven geotextile (as specified by StormTech) overtheir angular base stone. 2.1 INSPECTION The frequency of Inspection and Maintenance varies by location. A routine inspection schedule needs to be established for each individual location based upon site specific variables. The type of land use (i.e. industrial, commercial, residential), anticipated pollutant load, per- cent imperviousness, climate, etc. all play a critical role in determining the actual frequency of inspection and maintenance practices. At a minimum, StormTech recommends annual inspec- tions. Initially, the Isolator Row should be inspected every 6 months for the first year of operation. For sub sequent years, the inspection should be adjusted based upon previous observation of sediment deposition. The Isolator Row incorporates a combination of standard manhole(s) and strategically located inspection ports (as needed). The inspection ports allow for easy access to the system from the surface, eliminating the need to perform a confined space entry for inspection purposes. If upon visual inspection it is found that sediment has accumulated, a stadia rod should be inserted to deter- mine the depth of sediment. When the average depth of sediment exceeds 3 inches throughout the length of the Isolator Row, clean-out should be performed. 2.2 MAINTENANCE The Isolator Row was designed to reduce the cost of periodic maintenance. By “isolating” sediments to just one row, costs are dramatically reduced by eliminating the need to clean out each row of the entire storage bed. If inspection indicates the potential need for main- tenance, access is provided via a manhole(s) located on the end(s) of the row for cleanout. If entry into the manhole is required, please follow local and OSHA rules for a confined space entries. StormTech Isolator Row (not to scale) Examples of culvert cleaning nozzles appropriate for Isolator Row maintenance. (These are not StormTech products.) NOTE:NON-WOVEN FABRIC IS ONLY REQUIRED OVER THE INLET PIPE CONNECTION INTO THE END CAP FOR DC-780, MC-3500 AND MC-4500 CHAMBER MODELS AND IS NOT REQUIRED OVER THE ENTIRE ISOLATOR ROW. Step 1)Inspect Isolator Row for sediment A) Inspection ports (if present) i. Remove lid from floor box frame ii. Remove cap from inspection riser iii. Using a flashlight and stadia rod, measure depth of sediment and record results on maintenance log. iv. If sediment is at, or above, 3 inch depth proceed to Step 2. If not proceed to step 3. B) All Isolator Rows i. Remove cover from manhole at upstream end of Isolator Row ii. Using a flashlight, inspect down Isolator Row through outlet pipe 1.Mirrors on poles or cameras may be used to avoid a confined space entry 2.Follow OSHA regulations for confined space entry if entering manhole iii. If sediment is at or above the lower row of sidewall holes (approximately 3 inches) proceed to Step 2. If not proceed to Step 3. Step 2)Clean out Isolator Row using the JetVac process A) A fixed culvert cleaning nozzle with rear facing nozzle spread of 45 inches or more is preferable B) Apply multiple passes of JetVac until backflush water is clean C) Vacuum manhole sump as required Step 3) Replace all caps, lids and covers, record observations and actions Step 4)Inspect & clean catch basins and manholes upstream of the StormTech system ADS “Terms and Conditions of Sale” are available on the ADS website, www.ads-pipe.com Advanced Drainage Systems, the ADS logo, and the green stripe are registered trademarks of Advanced Drainage Systems. Stormtech®and the Isolator®Row are registered trademarks of StormTech, Inc. Green Building Council Member logo is a registered trademark of the U.S. Green Building Council. © 2013 Advanced Drainage Systems, Inc. SO90809 02/13 3.0 Isolator Row Step By Step Maintenance Procedures 4 21) B)1) A) StormTech Isolator Row (not to scale) Stadia Rod Readings Fixed point Fixed point Sediment Date to chamber to top of Depth Observations/Actions Inspector bottom (1) sediment (2) (1) - (2) 3/15/01 6.3 ft. none New installation. Fixed point is Cl frame at grade djm 9/24/01 6.2 0.1 ft. Some grit felt sm 6/20/03 5.8 0.5 ft. Mucky feel, debris visible in manhole and in rv Isolator row, maintenance due 7/7/03 6.3 ft.0 System jetted and vacuumed djm Sample Maintenance Log 70 Inwood Road, Suite 3 Rocky Hill Connecticut 06067 860.529.8188 888.892.2694 fax 866.328.8401 www.stormtech.com Detention • Retention • Water Quality A division of