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Home My WebLink AboutPOWERHOUSE 2 - PDP220006 - DOCUMENT MARKUPS - ROUND 3 - DRAINAGE REPORT PRELIMINARY DRAINAGE REPORT AND EROSION CONTROL REPORT POWERHOUSE 2 FORT COLLINS, COLORADO JUNE 29, 2022 NORTHERNENGINEERING.COM 970.221.4158 FORT COLLINS GREELEY This Drainage Report is consciously provided as a PDF. Please consider the environment before printing this document in its entirety. When a hard copy is necessary, we recommend double-sided printing. NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse 2 FORT COLLINS | GREELEY COVER LETTER June 29, 2022 City of Fort Collins Stormwater Utility 700 Wood Street Fort Collins, CO 80521 RE: PRELIMINARY DRAINAGE AND EROSION CONTROL REPORT FOR POWERHOUSE 2 Dear Staff: Northern Engineering is pleased to submit this Preliminary Drainage and Erosion Control Report for your review. This report accompanies the combined Project Development Plan (PDP) submittal for the proposed Powerhouse 2 development. This report has been prepared in accordance with the Fort Collins Stormwater Criteria Manual (FCSCM) and serves to document the stormwater impacts associated with the proposed Powerhouse 2 development. We understand review by the City of Fort Collins is to assure general compliance with standardized criteria contained in the FCSCM. If you have any questions as you review this report, please feel free to contact us. Sincerely, NORTHERN ENGINEERING SERVICES, INC. CARLOS ORTIZ GARCIA AUSTIN SNOW, PE Project Engineer Project Engineer NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse 2 FORT COLLINS | GREELEY TABLE OF CONTENTS TABLE OF CONTENTS This basin will generally drain via overland flow to the property adjacent to the west ost NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse 2 FORT COLLINS | GREELEY 1 | 10 This basin will generally drain via overland flow to the property adjacent to the west ost NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse 2 FORT COLLINS | GREELEY 2 | 10 This basin will generally drain via overland flow to the property adjacent to the west ost NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse 2 FORT COLLINS | GREELEY 3 | 10 C. FLOODPLAIN 1. The Powerhouse 2 project is located within a FEMA Special Flood Hazard Area of the Cache la Poudre River (Poudre River). Most of this area is designated as With Base Flood Elevation (BFE) or Depth in Zone AE on FIRM Panel 08069C0997G, effective June 17, 2008. The floodplain from the Whitewater Park Letter of Map Revision (LOMR) will supersede the current FEMA RiskMap. Therefore, most of the property falls inside the regulated 100-year floodplain. Chapter 10 of the City of Fort Collins Municipal Code regulates critical facilities within this Flood Hazard Zone. It should be noted FEMA, as part of RiskMap, is currently remapping the Poudre River. Anderson Consulting Engineers (ACE) will provide the updated Floodplain modeling, mapping and report for the site when completed. 2. Anderson Consulting Engineers is in the process of preparing a variance request to the Fort Collins Water Commission to allow construction of the Powerhouse 2 Building, which is considered to be a critical facility, within the currently effective 1% annual chance of occurrence (100-year) floodplain. Once constructed, the building will be elevated above, and mapped out of, both the 100-year and 0.2% annual chance (500-year) floodplains. The as-built condition will be documented in a LOMR to be submitted to the City and FEMA for review and adoption. However, since the building (as a critical facility) is planned to be constructed prior to the LOMR being approved by FEMA, a variance is required by City Code. The variance request also seeks to allow the City to issue a Certificate of Occupancy (CO) for the building once the City has reviewed and approved the LOMR application, but prior to final adoption by FEMA. It is currently anticipated that this variance request will come before the Water Commission in September 2022. 3. It is assumed a portion of the project site will continue to be located within the updated 100-year floodplain. To ensure the proposed buildings have adequate flood protection, the finished floors and all ductwork, heating, ventilation, electrical systems, etc., will be elevated 24-inches above Figure 4 – Area Floodplain Mapping This basin will generally drain via overland flow to the property adjacent to the west ost NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse 2 FORT COLLINS | GREELEY 4 | 10 the effective Base Flood Elevation (BFE). This elevation is known as the Regulatory Flood Protection Elevation (RFPE). The RFPE = BFE + 24 inches. The solar panels and the electric vehicle charging components in the parking lot shall be installed above the RFPE or have floodproofing as require by Chapter 10 of the City of Fort Collins Municipal Code. A minimum of 24-inches of freeboard will be provided from base (100-year) flood elevation (BFE). This freeboard level will be applied to either the design of finished floor elevations, or the minimum level of flood proofing measures Figure 5 – Foundation Detail 4. Furniture or site components not elevated above the floodplain or contained within a utility wall shall be securely anchored with a system of 4" lags bolts epoxied into ground base concrete or stone with straps and/or chains secured to elements to prevent flotation. 5. All elevators installed below the RFPE in the project will comply with FEMA NFIP technical bulletin 4 June 2019 and the 2021 IBC. 6. An emergency response and preparedness plan (ERPP) will be required by the City of Fort Collins prior to a floodplain or building permit being issued. 7. Outdoor classrooms are informal outdoor gathering space to be used for site tours and outdoor learning. These spaces will be constructed using large boulders and crusher-fine surfacing. 8. The vertical datum utilized for site survey work is the City of Fort Collins Benchmark # 1-00 (Elevation=4968.74); NAVD 88. 9. A floodplain use permit will be required for the building structure and each site construction element in the floodplain. The floodplain use permit for the building will be approved at the time of building permit application. 10. An elevation certificate will be completed before the Certificate of Occupancy (C.O.) is issued. This basin will generally drain via overland flow to the property adjacent to the west ost NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse 2 FORT COLLINS | GREELEY 5 | 10 This basin will generally drain via overland flow to the property adjacent to the west ost NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse 2 FORT COLLINS | GREELEY 6 | 10 proposed development. Tabulated data contained in Table 3.4-1 was utilized for Rational Method runoff calculations. This basin will generally drain via overland flow to the property adjacent to the west ost NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse 2 FORT COLLINS | GREELEY 7 | 10 Step 4 – Implement Site Specific and Other Source Control BMPs. This step typically applies to industrial and commercial developments. This basin will generally drain via overland flow to the property adjacent to the west ost NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse 2 FORT COLLINS | GREELEY 8 | 10 This basin will generally drain via overland flow to the property adjacent to the west ost NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse 2 FORT COLLINS | GREELEY 9 | 10 proposed area inlet located on East Vine Drive. Runoff from the basin will be routed to the Whitewater Park detention pond. Basins W8 & W10 Basin W8, approximately 0.63 acres, and Basin 10, approximately 1.50 acres, are part of the “Drainage, Water Quality and Erosion Control Report for the Poudre River Whitewater Park Project” drainage study. Runoff from the basins will follow the assumed fully-developed conceptual design path from the drainage study. Runoff will be routed to a proposed area inlet on East Vine Drive and then to Whitewater Park detention pond. Basin W11 Basin W11, approximately 0.89 acres, is part of the “Drainage, Water Quality and Erosion Control Report for the Poudre River Whitewater Park Project” drainage study. Runoff from the basin will follow the assumed fully-developed conceptual design path from the drainage study, and will be routed via storm drain to Whitewater Park detention pond in the future when the parcel is developed. This basin will generally drain via overland flow to the property adjacent to the west ost NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse 2 FORT COLLINS | GREELEY 10 | 10 This basin will generally drain via overland flow to the property adjacent to the west ost NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse 2 FORT COLLINS | GREELEY 11 | 10 NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse II FORT COLLINS | GREELEY APPENDIX APPENDIX A HYDROLOGIC COMPUTATIONS Runoff Coefficient1 Percent Impervious1 Project: Location: 0.95 100%Calc. By: 0.95 90%Date: 0.50 40% 0.50 40% 0.20 2% 0.20 2% Basin ID Basin Area (sq.ft.) Basin Area (acres) Asphalt, Concrete (acres)Rooftop (acres)Gravel (acres) Pavers (acres) Undeveloped: Greenbelts, Agriculture (acres) Lawns, Clayey Soil, Flat Slope < 2% (acres) Percent Impervious C2*Cf Cf = 1.00 C5*Cf Cf = 1.00 C10*Cf Cf = 1.00 C100*Cf Cf = 1.25 Imp. Areas lot 2 & 3 30,613 0.70 0.60 0.10 0.00 0.00 0.00 0.00 99% 0.95 0.95 0.95 1.00 Perv. Areas lot 2 & 3 20,004 0.46 0.00 0.00 0.32 0.00 0.00 0.14 28% 0.41 0.41 0.41 0.51 Imp. Areas lot 4 26,797 0.62 0.51 0.11 0.00 0.00 0.00 0.00 98% 0.95 0.95 0.95 1.00 Perv. Areas lot 4 139,212 3.20 0.00 0.00 3.08 0.00 0.00 0.11 39% 0.49 0.49 0.49 0.61 H1 216,626 4.97 1.11 0.20 3.40 0.00 0.00 0.25 54% 0.60 0.60 0.60 0.76 1 (North Rain Garden) 97,274 2.23 0.81 0.34 0.13 0.15 0.00 0.80 56% 0.63 0.63 0.63 0.78 2 32,182 0.74 0.41 0.00 0.32 0.00 0.00 0.02 72%0.74 0.74 0.74 0.93 3 (South Rain Garden) 31,334 0.72 0.11 0.55 0.00 0.00 0.00 0.05 85%0.90 0.90 0.90 1.00 4 4,748 0.11 0.10 0.00 0.00 0.00 0.00 0.00 96% 0.92 0.92 0.92 1.00 6 17,909 0.41 0.00 0.00 0.00 0.00 0.00 0.41 2% 0.20 0.20 0.20 0.25 5 5,988 0.14 0.03 0.00 0.00 0.00 0.00 0.10 27% 0.39 0.39 0.39 0.49 7 1,768 0.04 0.01 0.00 0.00 0.00 0.00 0.03 35% 0.45 0.45 0.45 0.56 8 4,818 0.11 0.03 0.00 0.00 0.00 0.00 0.08 31% 0.42 0.42 0.42 0.52 9 5,990 0.14 0.00 0.00 0.00 0.00 0.00 0.14 2% 0.20 0.20 0.20 0.25 10 1,258 0.03 0.00 0.00 0.00 0.00 0.00 0.03 2% 0.20 0.20 0.20 0.25 11 2,385 0.05 0.00 0.00 0.00 0.00 0.00 0.05 2% 0.20 0.20 0.20 0.25 12 6,264 0.14 0.07 0.00 0.00 0.00 0.00 0.07 52% 0.58 0.58 0.58 0.73 Co1 18,884 0.43 0.29 0.00 0.00 0.00 0.00 0.15 67% 0.70 0.70 0.70 0.87 W8 27,443 0.63 Information taken from "Drainage, Water Quality and Erosion Control Report for Poudre River Whitewater Park"90% W10 65,340 1.50 Information taken from "Drainage, Water Quality and Erosion Control Report for Poudre River Whitewater Park"90% W11 38,768 0.89 Information taken from "Drainage, Water Quality and Erosion Control Report for Poudre River Whitewater Park"85% 2, 4, 6 to Extended Detention Basin WQ 54,840 1.26 0.51 0.00 0.32 0.00 0.00 0.43 51% 0.58 0.58 0.58 0.72 1, 2, 3, 4 and 6 to Detention Pond 183,448 4.21 1.44 0.90 0.45 0.15 0.00 1.28 60% 0.66 0.66 0.66 0.82 Basins Not Detained Lawns and Landscaping: Combined Basins A,B & C 2) Composite Runoff Coefficient adjusted per Table 3.2-3 of the Fort Collins Stormwater Manual (FCSM). Lawns, Clayey Soil, Flat Slope < 2% USDA SOIL TYPE: C Undeveloped: Greenbelts, Agriculture Composite Runoff Coefficient2 1) Runoff coefficients per Tables 3.2-1 & 3.2 of the FCSM. Percent impervious per Tables 4.1-2 & 4.1-3 of the FCSM. Historic Basins: Developed Basins: DEVELOPED RUNOFF COEFFICIENT CALCULATIONS Asphalt, Concrete Rooftop Gravel Pavers Streets, Parking Lots, Roofs, Alleys, and Drives: Character of Surface:Powerhouse II Fort Collins C. Ortiz June 29, 2022 Notes: 1)Basins 1 and 3 are draining towards Rain Gardens (LID). 2) Extended Detention Basin WQ, consist of basins draining into detention pond that is not treated by LID. (2, 4, 6) 3) Basin 10 and 11 Drain to Lake Canal. 4) Basin 5 and 7 Drain to Vine Drive. 5) Basin 12 Drain to Jerome St. 6) Basin 8 and Co1 Drain to College Ave. Where: Length (ft) Elev Up Elev Down Slope (%) Ti 2-Yr (min) Ti 10-Yr (min) Ti 100-Yr (min) Length (ft) Elev Up Elev Down Slope (%)Surface n Flow Area3 (sq.ft.) WP3 (ft)R (ft)V (ft/s) Tt (min) Tc 2-Yr (min) Tc 100-Yr (min) imp. areas lot 2 & 3 Imp. Areas lot 2 & 3 119 65.00 64.17 0.70%3.45 3.45 2.30 327 64.17 61.50 0.82% Swale (8:1)0.04 8.00 16.12 0.50 2.41 2.26 5.71 5.00 perv. areas lot 2 & 3 Perv. Areas lot 2 & 3 119 65.00 64.17 0.70%15.89 15.89 13.54 327 64.17 61.50 0.82% Swale (8:1)0.04 8.00 16.12 0.50 2.41 2.26 12.48 12.48 imp. areas lot 4 Imp. Areas lot 4 119 63.75 61.60 1.81%2.51 2.51 1.67 181 61.60 60.41 0.66% Swale (8:1)0.04 8.00 16.12 0.50 2.16 1.39 5.00 5.00 perv. areas lot 4 Perv. Areas lot 4 119 63.75 61.60 1.81%10.23 10.23 8.18 181 61.60 60.41 0.66% Swale (8:1)0.04 8.00 16.12 0.50 2.16 1.39 11.62 9.57 1 (north rain garden) 1 (North Rain Garden)92 67.51 64.37 3.41%5.66 5.66 3.80 283 64.37 60.48 1.38% Swale (4:1)0.04 4.00 8.25 0.48 3.08 1.53 7.19 5.33 2 2 75 62.52 61.32 1.60%4.97 4.97 2.41 228 61.32 60.18 0.50% Gutter 0.02 3.61 19.18 0.19 2.31 1.64 6.61 5.00 3 (south rain garden) 3 (South Rain Garden)59 68.80 68.67 0.22%4.88 4.88 2.39 12 68.67 68.63 0.33% Gutter 0.04 3.61 19.18 0.19 0.81 0.25 5.13 5.00 4 4 38 68.48 62.60 15.39%0.84 0.84 0.46 117 62.60 60.58 1.73% Gutter 0.02 3.61 19.18 0.19 4.29 0.45 5.00 5.00 6 6 49 62.04 58.09 8.00%5.92 5.92 5.59 208 58.09 56.99 0.53% Swale (8:1)0.04 8.00 16.12 0.50 1.94 1.79 7.70 7.37 5 5 42 68.68 67.08 3.82%5.50 5.50 4.74 24 67.08 66.23 3.49% Gutter 0.02 3.61 19.18 0.19 6.09 0.07 5.57 5.00 7 7 27 62.36 61.21 4.27%3.89 3.89 3.22 28 61.21 60.35 3.11% Swale (8:1)0.02 8.00 16.12 0.50 10.98 0.04 5.00 5.00 8 8 21 68.77 67.69 5.12%3.39 3.39 2.87 25 67.69 67.05 2.60% Swale (8:1)0.04 8.00 16.12 0.50 4.31 0.10 5.00 5.00 9 9 53 67.99 65.10 5.46%6.95 6.95 6.57 49 65.10 64.37 1.49% Swale (6:1)0.04 6.00 12.17 0.49 3.24 0.25 7.21 6.82 10 10 5 65.85 63.45 52.86%0.96 0.96 0.90 4 63.45 61.20 55.01% Swale (8:1)0.04 8.00 16.12 0.50 19.79 0.00 5.00 5.00 11 11 6 63.42 63.29 2.19%3.16 3.16 2.98 8 63.29 63.11 2.16% Swale (8:1)0.04 8.00 16.12 0.50 3.93 0.04 5.00 5.00 12 12 27 63.56 62.85 2.65%3.62 3.62 2.60 34 62.85 62.50 1.03% Swale (8:1)0.04 8.00 16.12 0.50 2.71 0.21 5.00 5.00 co1 Co1 34 67.54 66.78 2.23%3.37 3.37 1.91 179 66.78 65.93 0.47% Gutter 0.02 3.61 19.18 0.19 2.25 1.33 5.00 5.00 w8 W8 Information taken from "Drainage, Water Quality and Erosion Control Report for Poudre River Whitewater Park" w10 W10 Information taken from "Drainage, Water Quality and Erosion Control Report for Poudre River Whitewater Park" w11 W11 Information taken from "Drainage, Water Quality and Erosion Control Report for Poudre River Whitewater Park" 2, 4, 6 to Extended Detention Basin WQ 49 62.04 58.09 8.00% 3.42 3.42 2.47 208 58.09 56.99 0.53% Swale (8:1) 0.04 8.00 16.12 0.50 1.94 1.79 5.21 5.00 1, 2, 3, 4 and 6 to Detention Pond 49 62.04 58.09 8.00% 2.91 2.91 1.83 208 58.09 56.99 0.53% Swale (6:1) 0.04 6.00 12.17 0.49 1.93 1.80 5.00 5.00 Design Point Basin ID Overland Flow Channelized Flow Time of Historic Basins: Developed Basins: Basins Not Detain Combined Basins DEVELOPED TIME OF CONCENTRATION COMPUTATIONS Maximum Tc:Overland Flow, Time of Concentration: Channelized Flow, Velocity:Channelized Flow, Time of Concentration: Powerhouse II Fort Collins C. Ortiz June 29, 2022 Notes S = Longitudinal Slope, feet/feet R = Hydraulic Radius (feet) n = Roughness Coefficient V = Velocity (ft/sec)WP = Wetted Perimeter (ft) (Equation 3.3-2 per Fort Collins Stormwater Manual)=1.87 1.1 − ∗ =1.49 ∗ /∗(Equation 5-4 per Fort Collins Stormwater Manual) =180 + 10 (Equation 3.3-5 per Fort Collins Stormwater Manual) =∗ 60 (Equation 5-5 per Fort Collins 1)Add 4900 to all elevations. 2) Per Fort Collins Stormwater Manual, minimum Tc = 5 min. 3) Assume a water depth of 6" and a typical curb and gutter per Larimer County Urban Street Standard Detail 701 for curb and gutter channelized flow. Assume a water depth of 1', fixed side Tc2 Tc10 Tc100 C2 C10 C100 I2 I10 I100 Q2 Q10 Q100 Historic Basins: imp. areas lot 2 & 3 Imp. Areas lot 2 & 3 0.70 5.7 5.7 5.0 1.0 1.0 1.0 2.8 4.7 10.0 1.8 3.1 7.0 perv. areas lot 2 & 3 Perv. Areas lot 2 & 3 0.46 12.5 12.5 12.5 0.4 0.4 0.5 2.1 3.5 7.2 0.4 0.7 1.7 imp. areas lot 4 Imp. Areas lot 4 0.62 5.0 5.0 5.0 0.9 0.9 1.0 2.9 4.9 10.0 1.7 2.8 6.1 perv. areas lot 4 Perv. Areas lot 4 3.20 11.6 11.6 9.6 0.5 0.5 0.6 2.1 3.6 7.9 3.3 5.6 15.4 Developed Basins: 1 (north rain garden) 1 (North Rain Garden) 2.23 7.2 7.2 5.3 0.6 0.6 0.8 2.5 4.3 10.0 3.5 6.0 17.4 2 2 0.74 6.6 6.6 5.0 0.7 0.7 0.9 2.6 4.4 10.0 1.4 2.4 6.8 3 (south rain garden) 3 (South Rain Garden) 0.72 5.1 5.1 5.0 0.9 0.9 1.0 2.9 4.9 10.0 1.8 3.1 7.2 4 4 0.11 5.0 5.0 5.0 0.9 0.9 1.0 2.9 4.9 10.0 0.3 0.5 1.1 6 6 0.41 7.7 7.7 7.4 0.2 0.2 0.3 2.5 4.2 8.8 0.2 0.3 0.9 5 5 0.14 5.6 5.6 5.0 0.4 0.4 0.5 2.8 4.7 10.0 0.1 0.3 0.7 7 7 0.04 5.0 5.0 5.0 0.4 0.4 0.6 2.9 4.9 10.0 0.1 0.1 0.2 8 8 0.11 5.0 5.0 5.0 0.4 0.4 0.5 2.9 4.9 10.0 0.13 0.23 0.58 9 9 0.14 7.2 7.2 6.8 0.2 0.2 0.3 2.5 4.3 9.1 0.07 0.12 0.31 10 10 0.03 5.0 5.0 5.0 0.2 0.2 0.3 2.9 4.9 10.0 0.02 0.03 0.07 11 11 0.05 5.0 5.0 5.0 0.2 0.2 0.3 2.9 4.9 10.0 0.03 0.05 0.14 12 12 0.14 5.0 5.0 5.0 0.6 0.6 0.7 2.9 4.9 10.0 0.24 0.41 1.04 co1 Co1 0.43 5.0 5.0 5.0 0.7 0.7 0.9 2.9 4.9 10.0 0.86 1.47 3.76 w8 W8 1.5 3.0 6.9 w10 W10 2.8 5.6 13.2 w11 W11 1.8 3.5 8.1 2, 4, 6 to Extended Detention Basin WQ 1.26 5.2 5.2 5.0 0.6 0.6 0.7 2.9 4.9 10.0 2.1 3.6 9.1 1, 2, 3, 4 and 6 to Detention Pond 4.21 5.0 5.0 5.0 0.7 0.7 0.8 2.9 4.9 10.0 7.9 13.5 34.5 DEVELOPED DIRECT RUNOFF COMPUTATIONS Intensity (in/hr)Flow (cfs) Powerhouse II C. Ortiz June 29, 2022 Design Point Basin Intensity, I, from Fig. 3.4.1 Fort Collins Stormwater Manual. Rational Equation: Q = CiA (Equation 6-1 per MHFD) Area (acres) Runoff CTc (Min) Date: Fort Collins Project: Location: Calc. By: Basins Not Detain Combined Basins Information taken from "Drainage, Water Quality and Erosion Control Report for Poudre River Whitewater Park" Information taken from "Drainage, Water Quality and Erosion Control Report for Poudre River Whitewater Park" Information taken from "Drainage, Water Quality and Erosion Control Report for Poudre River Whitewater Park" This basin will generally drain via overland flow to the property adjacent to the west ost NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse II FORT COLLINS | GREELEY APPENDIX APPENDIX B DETENTION POND COMPUTATION COG Pond No :1 6 100-yr 0.82 WQCV 1108 ft3 Area (A)=4.21 acres Detention 13038 ft3 Max Release Rate =8.50 cfs Total 0.32 ac-ft Time Time 100-yr Intensity Q100 Inflow (Runoff) Volume Outflow (Release) Volume Storage Detention Volume (mins)(secs) (in/hr) (cfs) (ft3)(ft3)(ft3) 5 300 9.950 34.35 10305 2550.0 7754.8 10 600 7.720 26.65 15991 5100.0 10890.6 15 900 6.520 22.51 20258 7650.0 12607.5 20 1200 5.600 19.33 23199 10200.0 12998.8 25 1500 4.980 17.19 25788 12750.0 13037.9 30 1800 4.520 15.60 28087 15300.0 12787.1 35 2100 4.080 14.08 29578 17850.0 11728.4 40 2400 3.740 12.91 30987 20400.0 10586.9 45 2700 3.460 11.94 32250 22950.0 9300.5 50 3000 3.230 11.15 33452 25500.0 7951.8 55 3300 3.030 10.46 34519 28050.0 6468.5 60 3600 2.860 9.87 35544 30600.0 4943.9 65 3900 2.720 9.39 36621 33150.0 3470.9 70 4200 2.590 8.94 37553 35700.0 1853.0 75 4500 2.480 8.56 38527 38250.0 276.6 80 4800 2.380 8.22 39438 40800.0 -1362.1 85 5100 2.290 7.91 40318 43350.0 -3031.8 90 5400 2.210 7.63 41199 45900.0 -4701.4 95 5700 2.130 7.35 41913 48450.0 -6536.8 100 6000 2.060 7.11 42669 51000.0 -8330.8 105 6300 2.000 6.90 43498 53550.0 -10052.3 110 6600 1.940 6.70 44202 56100.0 -11898.0 115 6900 1.890 6.52 45020 58650.0 -13629.9 120 7200 1.840 6.35 45735 61200.0 -15465.3 DETENTION POND CALCULATION; FAA METHOD Project Number : 207-030 Date :June 22, 2022 Project Location : Fort Collins, CO. Developed "C" = Calculations By: Input Variables Results Design Point Design Storm Required Detention Volume 1 Project: Date:6/27/2022 WQCV ELEVATION : (A) (B) (C) (D)Total Volume Detention = 1,306.79 0.03 Ac. Elevation Depth Area Volume Σ Volume Σ Volume Elev. (A1)=4,957.50 (Sf.)(Cf.) (Cf.) (Ac.-ft.)Σ Volume (D1)=488.77 Partial volume (C2)=1,723.69 Outlet Elevation:4,957.00 26.33 Depth, partial volume =0.50 0.50 488.77 488.77 0.01 >>>>>>>>> 4,957.50 1,928.75 High water level (HWL)=4957.74 0.50 1,723.69 2,212.46 0.05 4,958.00 4,966.00 Water Depth =0.74 Ft. 0.50 3,091.84 5,304.30 0.12 4,958.50 7,401.37 0.50 3,962.87 9,267.17 0.21 4,959.00 8,450.10 ACTUAL STORAGE : (A)(B)(C)(D)Total Volume Detention = 13,939.09 0.32 Ac. Elevation Depth Area Volume Σ Volume Σ Volume Elev. (A1)=4,959.00 (Sf.)(Cf.) (Cf.) (Ac.-ft.)Σ Volume (D1)=9,267.17 Partial volume (C2)=4,496.08 Outlet Elevation:4,957.00 26.33 Depth, partial volume =0.50 0.50 488.77 488.77 0.01 4,957.50 1,928.75 High water level (HWL)=4959.52 0.50 1,723.69 2,212.46 0.05 Free board =0.48 4,958.00 4,966.00 Top pond bank elevation =4960.00 0.50 3,091.84 5,304.30 0.12 4,958.50 7,401.37 Water Depth =2.52 Ft. Detention Req'd 0.50 3,962.87 9,267.17 0.21 >>>>>>>>> 4,959.00 8,450.10 0.50 4,496.08 13,763.25 0.32 4,959.50 9,534.21 0.50 5,085.15 18,848.39 0.43 4,960.00 10,806.37 Pond No.:1 Detention Pond Stage Storage Curve Pond Stage Storage Curve Project Number:207-030 Project Location:Fort Collins, Colorado Calculations By:C. Ortiz Powerhouse II 207-030 - D-pond_Capacity, Det. Pond-A1 2022-11, 6/27/2022, 5:34 PM Project Title Date: Project Number Calcs By: City Basins 1 WQCV = Watershed inches of Runoff (inches)60% a = Runoff Volume Reduction (constant) i = Total imperviousness Ratio (i = Iwq/100)0.236 in A =4.21 ac V = 0.10 ac-ft V = 1.2 x Water Quality Design Volume (ac-ft) WQCV = Water Quality Capture Volume (inches) A = Watershed Area (acres) Provided (LID) Rain Gardens = Volume to be provided in the Pond = 0.03 Ac-ft 3223 cu. ft. 1108 cu. ft. Powerhouse II June 22, 2022 207-030 C. Ortiz Fort Collins 4331 cu. ft. Drain Time a = i = WQCV = Figure EDB-2 - Water Quality Capture Volume (WQCV), 80th Percentile Runoff Event 1, 2, 3, 4, and 6 DETENTION POND Dp1 0.231 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 0.4 0.45 0.5 00.10.20.30.40.50.60.70.80.91WQCV (watershed inches)Total Imperviousness Ratio (i = Iwq/100) Water Quality Capture Volume 6 hr 12 hr 24 hr 40 hr ()iii78.019.10.91aWQCV 23 +-= ()iii78.019.10.91aWQCV 23 +-= AV* 12 WQCV   = 40 hr Stormwater Facility Name: Facility Location & Jurisdiction: User (Input) Watershed Characteristics User Defined User Defined User Defined User Defined Watershed Slope =0.005 ft/ft Stage [ft] Area [ft^2] Stage [ft] Discharge [cfs] Watershed Length-to-Width Ratio = 2.72 L:W 0.00 26 0.00 0.00 Watershed Area = 4.21 acres 0.50 1,929 0.50 3.20 Watershed Imperviousness = 60.0% percent 1.00 4,966 1.00 4.53 Percentage Hydrologic Soil Group A = 0.0% percent 1.50 7,401 1.50 5.99 Percentage Hydrologic Soil Group B = 0.0% percent 2.00 8,450 2.00 7.51 Percentage Hydrologic Soil Groups C/D = 100.0% percent 2.50 9,540 2.50 8.77 3.00 10,806 3.00 9.86 User Input: Detention Basin Characteristics WQCV Design Drain Time = 40.00 hours After completing and printing this worksheet to a pdf, go to: https://maperture.digitaldataservices.com/gvh/?viewer=cswdif, create a new stormwater facility, and attach the pdf of this worksheet to that record. Routed Hydrograph Results Design Storm Return Period =WQCV 2 Year 5 Year 10 Year 25 Year 50 Year 100 Year Two-Hour Rainfall Depth =0.53 0.98 1.36 1.71 2.31 2.91 3.67 in Calculated Runoff Volume =0.082 0.198 0.321 0.436 0.650 0.850 1.125 acre-ft OPTIONAL Override Runoff Volume =acre-ft Inflow Hydrograph Volume =0.081 0.198 0.320 0.436 0.650 0.849 1.125 acre-ft Time to Drain 97% of Inflow Volume =1 1 1 1 2 2 2 hours Time to Drain 99% of Inflow Volume =1 1 1 1 2 2 2 hours Maximum Ponding Depth =0.22 0.50 0.87 1.19 1.68 2.13 2.72 ft Maximum Ponded Area =0.020 0.044 0.095 0.135 0.179 0.200 0.232 acres Maximum Volume Stored =0.002 0.011 0.037 0.074 0.153 0.237 0.366 acre-ft Stormwater Detention and Infiltration Design Data Sheet Powerhouse II Fort Collins, Colorado Workbook Protected Worksheet Protected 6573312, Design Data 6/27/2022, 5:20 PM Doing_Clear_Formatting =Yes CountA=1 0 1 2 3 #N/A #N/A 0 1 2 3 #N/A #N/A Check Data Set 1 Check Data Set 1 Stormwater Detention and Infiltration Design Data Sheet Area Discharge 0 2 4 6 8 10 12 14 16 18 20 0.1 1 10FLOW [cfs]TIME [hr] 100YR IN 100YR OUT 50YR IN 50YR OUT 25YR IN 25YR OUT 10YR IN 10YR OUT 5YR IN 5YR OUT 2YR IN 2YR OUT WQCV IN WQCV OUT 0 0.5 1 1.5 2 2.5 3 0.1 1 10 100PONDING DEPTH [ft]DRAIN TIME [hr] 100YR 50YR 25YR 10YR 5YR 2YR WQCV 6573312, Design Data 6/27/2022, 5:20 PM This basin will generally drain via overland flow to the property adjacent to the west ost NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse II FORT COLLINS | GREELEY APPENDIX APPENDIX C INLETS & WEIRS (WILL BE SIZED AT FINAL) Channel Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc.Wednesday, Jun 22 2022 Swale Section 1 -1 Triangular Side Slopes (z:1) = 3.70, 10.80 Total Depth (ft) = 1.40 Invert Elev (ft) = 1.00 Slope (%)= 1.25 N-Value = 0.035 Calculations Compute by:Known Q Known Q (cfs) = 11.20 Highlighted Depth (ft)= 0.79 Q (cfs)= 11.20 Area (sqft)= 4.52 Velocity (ft/s)= 2.48 Wetted Perim (ft) = 11.60 Crit Depth, Yc (ft) = 0.69 Top Width (ft)= 11.45 EGL (ft)= 0.89 0 5 10 15 20 25 30 35 Elev (ft)Depth (ft)Section 0.50 -0.50 1.00 0.00 1.50 0.50 2.00 1.00 2.50 1.50 3.00 2.00 Reach (ft) This basin will generally drain via overland flow to the property adjacent to the west ost NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse II FORT COLLINS | GREELEY APPENDIX APPENDIX D EROSION CONTROL REPORT NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse II FORT COLLINS | GREELEY EROSION CONTROL REPORT EROSION CONTROL REPORT A comprehensive Erosion and Sediment Control Plan (along with associated details) will be included with the final construction drawings. It should be noted; however, any such Erosion and Sediment Control Plan serves only as a general guide to the Contractor. Staging and/or phasing of the BMPs depicted, and additional or different BMPs from those included may be necessary during construction, or as required by the authorities having jurisdiction. It shall be the responsibility of the Contractor to ensure erosion control measures are properly maintained and followed. The Erosion and Sediment Control Plan is intended to be a living document, constantly adapting to site conditions and needs. The Contractor shall update the location of BMPs as they are installed, removed, or modified in conjunction with construction activities. It is imperative to reflect the current site conditions appropriately always. The Erosion and Sediment Control Plan shall address both temporary measures to be implemented during construction, as well as permanent erosion control protection. Best Management Practices from the Volume 3, Chapter 7 – Construction BMPs will be utilized. Measures may include, but are not limited to, silt fencing and/or wattles along the disturbed perimeter, gutter protection in the adjacent roadways, and inlet protection at existing and proposed storm inlets. Vehicle tracking control pads, spill containment and clean-up procedures, designated concrete washout areas, dumpsters, and job site restrooms shall also be provided by the Contractor. Grading and Erosion Control Notes can be found on Sheet CS2 of the Utility Plans. The Final Utility Plans will also contain a full-size Erosion Control Plan as well as a separate sheet dedicated to Erosion Control Details. In addition to this report and the referenced plan sheets, the Contractor shall be aware of, and adhere to, the applicable requirements outlined in any existing Development Agreement(s) of record, as well as the Development Agreement, to be recorded prior to issuance of the Development Construction Permit. Also, the Site Contractor for this project may be required to secure a Stormwater Construction General Permit from the Colorado Department of Public Health and Environment (CDPHE), Water Quality Control Division – Stormwater Program, before commencing any earth disturbing activities. Prior to securing said permit, the Site Contractor shall develop a comprehensive Storm Water Management Plan (SWMP) pursuant to CDPHE requirements and guidelines. The SWMP will further describe and document the ongoing activities, inspections, and maintenance of construction BMPs. NNORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse II FORT COLLINS | GREELEY APPENDIX APPENDIX E PRELIMINARY LID DESIGN INFORMATION VAULTCABLETVAULTF.O.VAULTF.O.F.O.CONTROLIRRCONTROLIRR GASOHU OHULIDMH/ / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / /GASTFTFEAST VINE DRIVENORTH COLLEGE AVENUE JEROME STREET UGEUDUDUDUDSFWIRSOUTH RAIN GARDENSREQUIRED VOLUME: 756 CU. FT.MINIMUM FLAT AREA: 533 SFPROVIDED VOLUME: 1,281 CU. FT.PROVIDED FLAT AREA: 1,538 SFTREATMENT AREA: 28,639 SFNORTH RAIN GARDENREQUIRED VOLUME: 1,449 CU. FT.MINIMUM FLAT AREA: 1,089 SFPROVIDED VOLUME: 1,942 CU. FT.PROVIDED FLAT AREA: 2,234 SFTREATMENT AREA: 63.000 SFJEROME STREET LLC,216 E OAK STJEROME STREET STATION LLC,742 N COLLEGE AVELMC VENTURES LLC,742 N COLLEGE AVECITY OF FORT COLLINS405 N COLLEGE AVEMORAK KAREN LLC622 N COLLEGE AVECITY OF FORT COLLINS,740 N COLLEGE AVEPOWERHOUSE IISHEET NO:P:\207-030\DWG\DRNG\207-030_LID.DWG DRAWING REFERENCE:LID TREATMENT EXHIBITC. Ortiz 1" = 80'JUNE 2022LID-1DRAWN BY:SCALE:ISSUED:NOTES1. FOR LID RAIN GARDENS CALCULATIONS PLEASE REFER TO THEPRELIMINARY DRAINAGE REPORT, DATED JUNE 29, 2022.2. REFER TO UTILITY PLANS FOR POWERHOUSE II FOR ADDITIONALGRADING AND UTILITY INFORMATION.3. REFER TO LANDSCAPE PLANS FOR ADDITIONAL INFORMATION ONHARDSCAPES.4. REFER TO DRAINAGE EXHIBIT SHEET DR1 OF UTILITY PLANS FORSOIL AMENDMENT NOTESLEGENDPROPOSED CONTOURPROPOSED STORM SEWERPROPOSED SWALEEXISTING CONTOURPROPOSED CURB & GUTTERPROPERTY BOUNDARYPROPOSED INLETLID TREATMENT AREANORTH( IN FEET )01 INCH = 80 FEET8080EXTENDED DETENTIONTREATMENT AREAUNTREATED AREAPowerhouse II On-Site LID TreatmentProject SummaryTotal Impervious Area 114,856sfTarget Treatment Percentage75%Minimum Area to be Treated by LIDmeasures 86,142sfTreated Impervious Areas by TreatmentMethodRain Garden91,420sfTotal Treated Impervious Areas91,420sfPercent Total Project Area Treated79.6% Sheet 1 of 2 Designer: Company: Date: Project: Location: 1. Basin Storage Volume A) Effective Imperviousness of Tributary Area, Ia Ia =56.0 % (100% if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio (i = Ia/100)i = 0.560 C) Water Quality Capture Volume (WQCV) for a 12-hour Drain Time WQCV = 0.18 watershed inches (WQCV= 0.8 * (0.91* i3 - 1.19 * i2 + 0.78 * i) D) Contributing Watershed Area (including rain garden area)Area = 97,274 sq ft E) Water Quality Capture Volume (WQCV) Design Volume VWQCV =1,449 cu ft Vol = (WQCV / 12) * Area F) For Watersheds Outside of the Denver Region, Depth of d6 = in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VWQCV OTHER =1,998.0 cu ft Water Quality Capture Volume (WQCV) Design Volume H) User Input of Water Quality Capture Volume (WQCV) Design Volume VWQCV USER =cu ft (Only if a different WQCV Design Volume is desired) 2. Basin Geometry A) WQCV Depth (12-inch maximum)DWQCV =8 in B) Rain Garden Side Slopes (Z = 4 min., horiz. dist per unit vertical)Z = 5.00 ft / ft (Use "0" if rain garden has vertical walls) C) Mimimum Flat Surface Area AMin =1089 sq ft D) Actual Flat Surface Area AActual =2234 sq ft E) Area at Design Depth (Top Surface Area)ATop =3591 sq ft F) Rain Garden Total Volume VT=1,942 cu ft (VT= ((ATop + AActual) / 2) * Depth) 3. Growing Media 4. Underdrain System A) Are underdrains provided? B) Underdrain system orifice diameter for 12 hour drain time i) Distance From Lowest Elevation of the Storage y =N/A ft Volume to the Center of the Orifice ii) Volume to Drain in 12 Hours Vol12 =N/A cu ft iii) Orifice Diameter, 3/8" Minimum DO =N/A in Design Procedure Form: Rain Garden (RG) C. Ortiz Northern Engineering June 22, 2022 Powerhouse II North Rain Garden (Basin 1) UD-BMP (Version 3.06, November 2016) Sheet 2 of 2 Designer: Company: Date: Project: Location: 5. Impermeable Geomembrane Liner and Geotextile Separator Fabric A) Is an impermeable liner provided due to proximity of structures or groundwater contamination? 6. Inlet / Outlet Control A) Inlet Control 7. Vegetation 8. Irrigation A) Will the rain garden be irrigated? Notes: Design Procedure Form: Rain Garden (RG) C. Ortiz Northern Engineering June 22, 2022 Powerhouse II North Rain Garden (Basin 1) Sheet 1 of 2 Designer: Company: Date: Project: Location: 1. Basin Storage Volume A) Effective Imperviousness of Tributary Area, Ia Ia =85.0 % (100% if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio (i = Ia/100)i = 0.850 C) Water Quality Capture Volume (WQCV) for a 12-hour Drain Time WQCV = 0.29 watershed inches (WQCV= 0.8 * (0.91* i3 - 1.19 * i2 + 0.78 * i) D) Contributing Watershed Area (including rain garden area)Area = 31,334 sq ft E) Water Quality Capture Volume (WQCV) Design Volume VWQCV =756 cu ft Vol = (WQCV / 12) * Area F) For Watersheds Outside of the Denver Region, Depth of d6 = in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VWQCV OTHER =884.0 cu ft Water Quality Capture Volume (WQCV) Design Volume H) User Input of Water Quality Capture Volume (WQCV) Design Volume VWQCV USER =cu ft (Only if a different WQCV Design Volume is desired) 2. Basin Geometry A) WQCV Depth (12-inch maximum)DWQCV =10 in B) Rain Garden Side Slopes (Z = 4 min., horiz. dist per unit vertical)Z = 4.00 ft / ft (Use "0" if rain garden has vertical walls) C) Mimimum Flat Surface Area AMin =533 sq ft D) Actual Flat Surface Area AActual =1538 sq ft E) Area at Design Depth (Top Surface Area)ATop =1538 sq ft F) Rain Garden Total Volume VT=1,281 cu ft (VT= ((ATop + AActual) / 2) * Depth) 3. Growing Media 4. Underdrain System A) Are underdrains provided? B) Underdrain system orifice diameter for 12 hour drain time i) Distance From Lowest Elevation of the Storage y =N/A ft Volume to the Center of the Orifice ii) Volume to Drain in 12 Hours Vol12 =N/A cu ft iii) Orifice Diameter, 3/8" Minimum DO =N/A in Design Procedure Form: Rain Garden (RG) C. Ortiz Northern Engineering June 22, 2022 Powerhouse II South Rain Garden (Basin 3) UD-BMP (Version 3.06, November 2016) Sheet 2 of 2 Designer: Company: Date: Project: Location: 5. Impermeable Geomembrane Liner and Geotextile Separator Fabric A) Is an impermeable liner provided due to proximity of structures or groundwater contamination? 6. Inlet / Outlet Control A) Inlet Control 7. Vegetation 8. Irrigation A) Will the rain garden be irrigated? Notes: Design Procedure Form: Rain Garden (RG) C. Ortiz Northern Engineering June 22, 2022 Powerhouse II South Rain Garden (Basin 3) NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse II FORT COLLINS | GREELEY APPENDIX APPENDIX F PREVIOUS STUDIES AND USDA SOILS REPORT DRAINAGE, WATER QUALITY AND EROSION CONTROL REPORT FOR THE POUDRE RIVER WHITEWATER PARK PROJECT PREPARED FOR: City of Fort Collins Park Planning & Development 215 North Mason Street Fort Collins, CO 80524 PREPARED BY: Anderson Consulting Engineers, Inc. 375 East Horsetooth Road, Building 5 Fort Collins, CO 80525 (ACE Project No. COFC18.1) June 6, 2017 COFC18.1 Drainage Report (June 6 2017).docx 3 Anderson Consulting Engineers, Inc. Figure 2.1 Site Map for the Poudre River Whitewater Project. Cache L a P o u d r e Ri ver Vine Dr Linden StreetCherry St College AveProject Area Union Pacific RailroadB urlington N orthern R ailroadJerome St0 500 1,000250 Feet COFC18.1 Drainage Report (June 6 2017).docx 14 Anderson Consulting Engineers, Inc. • Poudre River Pedestrian Bridge: As part of the City’s masterplan for the Poudre River Trail system, the trail will eventually be relocated to the northern side of the river between Linden Street and the BNSF Railroad when improvements to the Linde Street Bridge are implemented. In order to reconnect Poudre River trail users with the current trail as it passes underneath College Avenue, and to provide a pedestrian connection across the river for residents and businesses in northern Fort Collins, a new pedestrian bridge will be installed across the Poudre River as part of the project. The bridge will be 185-feet long and 15-feet wide. As identified on the Floodplain Plan provided as part of the Utility Plan drawings, the low chord elevation of the bridge (4964.0 NAVD88) will be located approximately 0.5-feet above the proposed/post-project base flood elevation of 4963.5. The bridge will also span the proposed/post-project floodway limits and a minimum 8-foot clearance will be provided between the low chord and proposed trails beneath the bridge. Since the bridge will be located above the base flood elevation, it will be designed as a non-breakaway bridge and will be incorporated into the hydraulic modeling conducted for the CLOMR/LOMR as part of this project. 5.2 Fully Developed Project Conditions Based on coordination with City stormwater staff, it was decided that a fully developed condition scenario would be developed to evaluate the sizing of proposed project infrastructure to accommodate fully developed conditions, as well as generate a conceptual drainage plan for future improvements. A figure depicting the fully developed project condition conveyance elements is provided as Sheet 2 in Appendix C. Tabular results from the fully developed project condition EPA SWMM model are also provided in Appendix C. Electronic copies of the fully developed project conditions EPA SWMM models are provided as digital data on the disk included with this report. A description of the fully developed proposed project condition is provided below: • Fully Developed Basins and Conceptual Detention Ponds: Subbasins 9, 11, 13, and 14 were assumed to be fully developed with increased impervious areas. Per the direction of City Stormwater staff, conceptual detention ponds were assumed for the three privately owned properties located north of Vine Drive (Subbasins 9, 11, and 14) to detain and release fully developed 100-year flows to a 2-year historic rate. It is noted that the conceptual detention ponds were simulated with a two-point rating curve. Conceptual detention for Subbasin 13 was not assumed per the development agreement between the City and the developer for this property. Fully developed flows from this basin will be conveyed underneath Vine Drive and into the water quality pond via the existing storm sewer system that was installed as part of the Innosphere development (Subbasin 12). COFC18.1 Drainage Report (June 6 2017).docx 15 Anderson Consulting Engineers, Inc. • Conceptual Future Vine Drive Improvements: In order to meet stormwater criteria, a 5-foot Type R inlet was conceptually assumed in the sump area on the n orth side of Vine Drive. Flow collected by this inlet, along with the detained released from Subbasins 9 and 11 is conceptually conveyed underneath Vine Drive in an 18-inch pipe. This pipe conceptually connects to the inlet on the south side of the street and into the storm drainage system proposed by the project. The installation of the inlet on the north side of the street will reduce the frequency of road overtopping for events less than the 50-year. Basin NameArea (ac) Width (ft)*OFL (ft) % Slope% Impervious (Proposed Conditions) % Impervious (Fully Developed)Description for Fully Developed ConditionB-1 2.78 1211 100 2.00 6060Assumes 100% impervious for ponded areaB-2 3.34 1455 100 3.00 5050 Assumes 100% impervious for ponded areaB-3 0.56 76 320 1.20 9090B-4 0.35 152 100 0.50 9090B-5 0.80 290 120 2.00 7575B-6 0.33 287 50 2.00 7575B-7 1.38 194 310 1.00 5050 Assumes 100% impervious for ponded areaB-8 0.74 101 320 1.20 9090B-9 4.68 371 550 1.00 4585 Assumes property is fully developedB-10 1.50 163 400 0.90 9090B-11 0.89 194 200 0.50 4585 Assumes property is fully developedB-12 2.50 573 190 4.40 8585B-13 2.77 710 170 1.00 2585 Assumes property is fully developedB-142.514972200.502585Assumes property is fully developed*Width is calculated from area and Overland Flow Length (OFL)SWMM MODEL INPUT PARAMETERS Basin Name Area (ac) 2-Year Peak Runoff (cfs) 10-Year Peak Runoff (cfs) 100-Year Peak Runoff (cfs) 100-Year Peak Unit Runoff Rate (cfs/acre) B-1 2.78 4.8 10.5 25.6 9.2 B-2 3.34 4.8 11.1 29.3 8.8 B-3 0.56 1.2 2.3 5.2 9.3 B-4 0.35 0.8 1.6 3.4 9.8 B-5 0.80 1.7 3.4 7.7 9.6 B-6 0.33 0.7 1.5 3.3 9.8 B-7 1.38 1.8 3.6 9.2 6.6 B-8 0.74 1.5 3.0 6.9 9.3 B-9 4.68 7.5 15.7 38.3 8.2 B-10 1.50 2.8 5.6 13.2 8.8 B-11 0.89 1.8 3.5 8.1 9.1 B-12 2.50 5.9 11.5 24.6 9.9 B-13 2.77 6.2 11.9 26.6 9.6 B-14 2.51 4.9 9.8 22.7 9.0 FULLY DEVELOPED CONDITION BASIN RUNOFF RESULTS SWMM Element 2-Year Peak Discharge (cfs) 10-Year Peak Runoff (cfs) 100-Year Peak Runoff (cfs)Description D-6 1.8 3.5 8.1 P-17 0.8 0.9 1.1 N-7 0.8 0.9 1.1 P-16 0.8 0.9 1.1 D-5 7.5 15.7 38.3 P-15 3.1 3.9 5.0 N-6 1.5 3.0 7.3 S-3 0.0 0.0 4.2 N-14 2.8 5.6 16.6 S-4 0.0 0.0 7.3 P-14 2.8 5.6 6.7 N-13 5.3 7.0 9.4 P-13 5.3 7.0 9.4 P-7 1.5 3.0 3.0 N-5 2.7 5.3 7.0 P-6 2.7 5.1 5.7 S-2 0.0 0.0 1.0 N-4 6.0 8.6 12.6 P-5 6.0 8.6 10.2 N-3 8.7 13.7 22.5 S-1 7.7 12.3 20.1 N-2 7.7 12.3 20.1 P-4 7.5 11.6 18.5 D-1 10.7 20.8 40.1 P-3 6.8 12.3 23.2 D-4 4.9 9.8 22.7 P-12 1.2 1.4 1.8 N-12 1.2 1.4 1.8 P-11 1.2 1.4 1.8 N-11 1.7 1.7 1.9 P-10 1.3 2.1 2.1 N-10 6.2 11.9 26.6 S-6 5.5 11.4 26.0 N-9 12.0 23.7 50.9 P-9 12.0 20.1 50.9 N-8 12.0 20.1 50.9 P-8 11.8 20.1 50.9 D-3 14.2 24.4 63.3 S-5 2.8 12.9 44.0 D-2 6.5 19.4 76.0 P-2 4.1 8.1 11.4 N-1 9.6 19.3 32.4 P-1 9.6 19.3 32.4 O-1 9.6 19.3 32.4 FULLY DEVELOPED CONDITION DISCHARGE RESULTS Western Flow PathEastern Flow PathOut-fall COLLEGE AVENUE CACHE LA POUDRE RIVERBNSF RAILROADUNION PACIFIC RAILROAD JEROME STREETLINDEN STREET R E D W O O D S T R E E TVINE DRIVECOY DITCHCOY DITCHLAKE CANALLAKE CANALAnderson Consulting Engineers, Inc Civil ▪ Water Resources ▪ Environmental 375 East Horsetooth Road, Building 5, Fort Collins, CO 80525 Phone (970) 226-0120 / Fax (970) 226-0121 www.acewater.com CITY OF FORT COLLINS POUDRE RIVER WHITEWATER PARK FULLY DEVELOPED CONDITION SUBBASIN AND CONVEYANCE ELEMENTS MAP2 United States Department of Agriculture A product of the National Cooperative Soil Survey, a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local participants Custom Soil Resource Report for Larimer County Area, Colorado 207-030 Powerhouse II Natural Resources Conservation Service January 13, 2022 Preface Soil surveys contain information that affects land use planning in survey areas. They highlight soil limitations that affect various land uses and provide information about the properties of the soils in the survey areas. Soil surveys are designed for many different users, including farmers, ranchers, foresters, agronomists, urban planners, community officials, engineers, developers, builders, and home buyers. Also, conservationists, teachers, students, and specialists in recreation, waste disposal, and pollution control can use the surveys to help them understand, protect, or enhance the environment. Various land use regulations of Federal, State, and local governments may impose special restrictions on land use or land treatment. Soil surveys identify soil properties that are used in making various land use or land treatment decisions. The information is intended to help the land users identify and reduce the effects of soil limitations on various land uses. The landowner or user is responsible for identifying and complying with existing laws and regulations. Although soil survey information can be used for general farm, local, and wider area planning, onsite investigation is needed to supplement this information in some cases. Examples include soil quality assessments (http://www.nrcs.usda.gov/wps/ portal/nrcs/main/soils/health/) and certain conservation and engineering applications. For more detailed information, contact your local USDA Service Center (https://offices.sc.egov.usda.gov/locator/app?agency=nrcs) or your NRCS State Soil Scientist (http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/contactus/? cid=nrcs142p2_053951). Great differences in soil properties can occur within short distances. Some soils are seasonally wet or subject to flooding. Some are too unstable to be used as a foundation for buildings or roads. Clayey or wet soils are poorly suited to use as septic tank absorption fields. A high water table makes a soil poorly suited to basements or underground installations. The National Cooperative Soil Survey is a joint effort of the United States Department of Agriculture and other Federal agencies, State agencies including the Agricultural Experiment Stations, and local agencies. The Natural Resources Conservation Service (NRCS) has leadership for the Federal part of the National Cooperative Soil Survey. Information about soils is updated periodically. Updated information is available through the NRCS Web Soil Survey, the site for official soil survey information. The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, age, disability, and where applicable, sex, marital status, familial status, parental status, religion, sexual orientation, genetic information, political beliefs, reprisal, or because all or a part of an individual's income is derived from any public assistance program. (Not all prohibited bases apply to all programs.) Persons with disabilities who require 2 alternative means for communication of program information (Braille, large print, audiotape, etc.) should contact USDA's TARGET Center at (202) 720-2600 (voice and TDD). To file a complaint of discrimination, write to USDA, Director, Office of Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410 or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer. 3 Contents Preface....................................................................................................................2 How Soil Surveys Are Made..................................................................................5 Soil Map..................................................................................................................8 Soil Map................................................................................................................9 Legend................................................................................................................10 Map Unit Legend................................................................................................11 Map Unit Descriptions.........................................................................................11 Larimer County Area, Colorado......................................................................13 73—Nunn clay loam, 0 to 1 percent slopes.................................................13 81—Paoli fine sandy loam, 0 to 1 percent slopes.......................................14 105—Table Mountain loam, 0 to 1 percent slopes......................................15 Soil Information for All Uses...............................................................................17 Soil Properties and Qualities..............................................................................17 Soil Qualities and Features.............................................................................17 Hydrologic Soil Group.................................................................................17 References............................................................................................................22 4 How Soil Surveys Are Made Soil surveys are made to provide information about the soils and miscellaneous areas in a specific area. They include a description of the soils and miscellaneous areas and their location on the landscape and tables that show soil properties and limitations affecting various uses. Soil scientists observed the steepness, length, and shape of the slopes; the general pattern of drainage; the kinds of crops and native plants; and the kinds of bedrock. They observed and described many soil profiles. A soil profile is the sequence of natural layers, or horizons, in a soil. The profile extends from the surface down into the unconsolidated material in which the soil formed or from the surface down to bedrock. The unconsolidated material is devoid of roots and other living organisms and has not been changed by other biological activity. Currently, soils are mapped according to the boundaries of major land resource areas (MLRAs). MLRAs are geographically associated land resource units that share common characteristics related to physiography, geology, climate, water resources, soils, biological resources, and land uses (USDA, 2006). Soil survey areas typically consist of parts of one or more MLRA. The soils and miscellaneous areas in a survey area occur in an orderly pattern that is related to the geology, landforms, relief, climate, and natural vegetation of the area. Each kind of soil and miscellaneous area is associated with a particular kind of landform or with a segment of the landform. By observing the soils and miscellaneous areas in the survey area and relating their position to specific segments of the landform, a soil scientist develops a concept, or model, of how they were formed. Thus, during mapping, this model enables the soil scientist to predict with a considerable degree of accuracy the kind of soil or miscellaneous area at a specific location on the landscape. Commonly, individual soils on the landscape merge into one another as their characteristics gradually change. To construct an accurate soil map, however, soil scientists must determine the boundaries between the soils. They can observe only a limited number of soil profiles. Nevertheless, these observations, supplemented by an understanding of the soil-vegetation-landscape relationship, are sufficient to verify predictions of the kinds of soil in an area and to determine the boundaries. Soil scientists recorded the characteristics of the soil profiles that they studied. They noted soil color, texture, size and shape of soil aggregates, kind and amount of rock fragments, distribution of plant roots, reaction, and other features that enable them to identify soils. After describing the soils in the survey area and determining their properties, the soil scientists assigned the soils to taxonomic classes (units). Taxonomic classes are concepts. Each taxonomic class has a set of soil characteristics with precisely defined limits. The classes are used as a basis for comparison to classify soils systematically. Soil taxonomy, the system of taxonomic classification used in the United States, is based mainly on the kind and character of soil properties and the arrangement of horizons within the profile. After the soil 5 scientists classified and named the soils in the survey area, they compared the individual soils with similar soils in the same taxonomic class in other areas so that they could confirm data and assemble additional data based on experience and research. The objective of soil mapping is not to delineate pure map unit components; the objective is to separate the landscape into landforms or landform segments that have similar use and management requirements. Each map unit is defined by a unique combination of soil components and/or miscellaneous areas in predictable proportions. Some components may be highly contrasting to the other components of the map unit. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The delineation of such landforms and landform segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, onsite investigation is needed to define and locate the soils and miscellaneous areas. Soil scientists make many field observations in the process of producing a soil map. The frequency of observation is dependent upon several factors, including scale of mapping, intensity of mapping, design of map units, complexity of the landscape, and experience of the soil scientist. Observations are made to test and refine the soil-landscape model and predictions and to verify the classification of the soils at specific locations. Once the soil-landscape model is refined, a significantly smaller number of measurements of individual soil properties are made and recorded. These measurements may include field measurements, such as those for color, depth to bedrock, and texture, and laboratory measurements, such as those for content of sand, silt, clay, salt, and other components. Properties of each soil typically vary from one point to another across the landscape. Observations for map unit components are aggregated to develop ranges of characteristics for the components. The aggregated values are presented. Direct measurements do not exist for every property presented for every map unit component. Values for some properties are estimated from combinations of other properties. While a soil survey is in progress, samples of some of the soils in the area generally are collected for laboratory analyses and for engineering tests. Soil scientists interpret the data from these analyses and tests as well as the field-observed characteristics and the soil properties to determine the expected behavior of the soils under different uses. Interpretations for all of the soils are field tested through observation of the soils in different uses and under different levels of management. Some interpretations are modified to fit local conditions, and some new interpretations are developed to meet local needs. Data are assembled from other sources, such as research information, production records, and field experience of specialists. For example, data on crop yields under defined levels of management are assembled from farm records and from field or plot experiments on the same kinds of soil. Predictions about soil behavior are based not only on soil properties but also on such variables as climate and biological activity. Soil conditions are predictable over long periods of time, but they are not predictable from year to year. For example, soil scientists can predict with a fairly high degree of accuracy that a given soil will have a high water table within certain depths in most years, but they cannot predict that a high water table will always be at a specific level in the soil on a specific date. After soil scientists located and identified the significant natural bodies of soil in the survey area, they drew the boundaries of these bodies on aerial photographs and Custom Soil Resource Report 6 identified each as a specific map unit. Aerial photographs show trees, buildings, fields, roads, and rivers, all of which help in locating boundaries accurately. Custom Soil Resource Report 7 Soil Map The soil map section includes the soil map for the defined area of interest, a list of soil map units on the map and extent of each map unit, and cartographic symbols displayed on the map. Also presented are various metadata about data used to produce the map, and a description of each soil map unit. 8 9 Custom Soil Resource Report Soil Map 4493890449392044939504493980449401044940404494070449410044938904493920449395044939804494010449404044940704494100493480 493510 493540 493570 493600 493630 493660 493690 493720 493750 493780 493810 493480 493510 493540 493570 493600 493630 493660 493690 493720 493750 493780 493810 40° 35' 51'' N 105° 4' 37'' W40° 35' 51'' N105° 4' 23'' W40° 35' 44'' N 105° 4' 37'' W40° 35' 44'' N 105° 4' 23'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 50 100 200 300Feet 0 20 40 80 120Meters Map Scale: 1:1,530 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Map Unit Polygons Soil Map Unit Lines Soil Map Unit Points Special Point Features Blowout Borrow Pit Clay Spot Closed Depression Gravel Pit Gravelly Spot Landfill Lava Flow Marsh or swamp Mine or Quarry Miscellaneous Water Perennial Water Rock Outcrop Saline Spot Sandy Spot Severely Eroded Spot Sinkhole Slide or Slip Sodic Spot Spoil Area Stony Spot Very Stony Spot Wet Spot Other Special Line Features Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Larimer County Area, Colorado Survey Area Data: Version 16, Sep 2, 2021 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Aug 11, 2018—Aug 12, 2018 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 10 Map Unit Legend Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI 73 Nunn clay loam, 0 to 1 percent slopes 3.0 30.5% 81 Paoli fine sandy loam, 0 to 1 percent slopes 0.9 8.8% 105 Table Mountain loam, 0 to 1 percent slopes 6.0 60.7% Totals for Area of Interest 9.8 100.0% Map Unit Descriptions The map units delineated on the detailed soil maps in a soil survey represent the soils or miscellaneous areas in the survey area. The map unit descriptions, along with the maps, can be used to determine the composition and properties of a unit. A map unit delineation on a soil map represents an area dominated by one or more major kinds of soil or miscellaneous areas. A map unit is identified and named according to the taxonomic classification of the dominant soils. Within a taxonomic class there are precisely defined limits for the properties of the soils. On the landscape, however, the soils are natural phenomena, and they have the characteristic variability of all natural phenomena. Thus, the range of some observed properties may extend beyond the limits defined for a taxonomic class. Areas of soils of a single taxonomic class rarely, if ever, can be mapped without including areas of other taxonomic classes. Consequently, every map unit is made up of the soils or miscellaneous areas for which it is named and some minor components that belong to taxonomic classes other than those of the major soils. Most minor soils have properties similar to those of the dominant soil or soils in the map unit, and thus they do not affect use and management. These are called noncontrasting, or similar, components. They may or may not be mentioned in a particular map unit description. Other minor components, however, have properties and behavioral characteristics divergent enough to affect use or to require different management. These are called contrasting, or dissimilar, components. They generally are in small areas and could not be mapped separately because of the scale used. Some small areas of strongly contrasting soils or miscellaneous areas are identified by a special symbol on the maps. If included in the database for a given area, the contrasting minor components are identified in the map unit descriptions along with some characteristics of each. A few areas of minor components may not have been observed, and consequently they are not mentioned in the descriptions, especially where the pattern was so complex that it was impractical to make enough observations to identify all the soils and miscellaneous areas on the landscape. The presence of minor components in a map unit in no way diminishes the usefulness or accuracy of the data. The objective of mapping is not to delineate pure taxonomic classes but rather to separate the landscape into landforms or Custom Soil Resource Report 11 landform segments that have similar use and management requirements. The delineation of such segments on the map provides sufficient information for the development of resource plans. If intensive use of small areas is planned, however, onsite investigation is needed to define and locate the soils and miscellaneous areas. An identifying symbol precedes the map unit name in the map unit descriptions. Each description includes general facts about the unit and gives important soil properties and qualities. Soils that have profiles that are almost alike make up a soil series. Except for differences in texture of the surface layer, all the soils of a series have major horizons that are similar in composition, thickness, and arrangement. Soils of one series can differ in texture of the surface layer, slope, stoniness, salinity, degree of erosion, and other characteristics that affect their use. On the basis of such differences, a soil series is divided into soil phases. Most of the areas shown on the detailed soil maps are phases of soil series. The name of a soil phase commonly indicates a feature that affects use or management. For example, Alpha silt loam, 0 to 2 percent slopes, is a phase of the Alpha series. Some map units are made up of two or more major soils or miscellaneous areas. These map units are complexes, associations, or undifferentiated groups. A complex consists of two or more soils or miscellaneous areas in such an intricate pattern or in such small areas that they cannot be shown separately on the maps. The pattern and proportion of the soils or miscellaneous areas are somewhat similar in all areas. Alpha-Beta complex, 0 to 6 percent slopes, is an example. An association is made up of two or more geographically associated soils or miscellaneous areas that are shown as one unit on the maps. Because of present or anticipated uses of the map units in the survey area, it was not considered practical or necessary to map the soils or miscellaneous areas separately. The pattern and relative proportion of the soils or miscellaneous areas are somewhat similar. Alpha-Beta association, 0 to 2 percent slopes, is an example. An undifferentiated group is made up of two or more soils or miscellaneous areas that could be mapped individually but are mapped as one unit because similar interpretations can be made for use and management. The pattern and proportion of the soils or miscellaneous areas in a mapped area are not uniform. An area can be made up of only one of the major soils or miscellaneous areas, or it can be made up of all of them. Alpha and Beta soils, 0 to 2 percent slopes, is an example. Some surveys include miscellaneous areas. Such areas have little or no soil material and support little or no vegetation. Rock outcrop is an example. Custom Soil Resource Report 12 Larimer County Area, Colorado 73—Nunn clay loam, 0 to 1 percent slopes Map Unit Setting National map unit symbol: 2tlng Elevation: 4,100 to 5,700 feet Mean annual precipitation: 14 to 15 inches Mean annual air temperature: 48 to 52 degrees F Frost-free period: 135 to 152 days Farmland classification: Prime farmland if irrigated Map Unit Composition Nunn and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Nunn Setting Landform:Terraces Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Parent material:Pleistocene aged alluvium and/or eolian deposits Typical profile Ap - 0 to 6 inches: clay loam Bt1 - 6 to 10 inches: clay loam Bt2 - 10 to 26 inches: clay loam Btk - 26 to 31 inches: clay loam Bk1 - 31 to 47 inches: loam Bk2 - 47 to 80 inches: loam Properties and qualities Slope:0 to 1 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Medium Capacity of the most limiting layer to transmit water (Ksat):Moderately low to moderately high (0.06 to 0.20 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:7 percent Maximum salinity:Nonsaline (0.1 to 1.0 mmhos/cm) Sodium adsorption ratio, maximum:0.5 Available water supply, 0 to 60 inches: High (about 9.1 inches) Interpretive groups Land capability classification (irrigated): 3e Land capability classification (nonirrigated): 4e Hydrologic Soil Group: C Ecological site: R067BY042CO - Clayey Plains Hydric soil rating: No Custom Soil Resource Report 13 Minor Components Heldt Percent of map unit:10 percent Landform:Terraces Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY042CO - Clayey Plains Hydric soil rating: No Wages Percent of map unit:5 percent Landform:Terraces Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Ecological site:R067BY002CO - Loamy Plains Hydric soil rating: No 81—Paoli fine sandy loam, 0 to 1 percent slopes Map Unit Setting National map unit symbol: jpxx Elevation: 4,800 to 5,600 feet Mean annual precipitation: 13 to 15 inches Mean annual air temperature: 48 to 50 degrees F Frost-free period: 135 to 150 days Farmland classification: Prime farmland if irrigated Map Unit Composition Paoli and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Description of Paoli Setting Landform:Stream terraces Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Parent material:Alluvium Typical profile H1 - 0 to 30 inches: fine sandy loam H2 - 30 to 60 inches: fine sandy loam Properties and qualities Slope:0 to 1 percent Custom Soil Resource Report 14 Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Very low Capacity of the most limiting layer to transmit water (Ksat):High (2.00 to 6.00 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:15 percent Maximum salinity:Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm) Available water supply, 0 to 60 inches: Moderate (about 8.7 inches) Interpretive groups Land capability classification (irrigated): 1 Land capability classification (nonirrigated): 3c Hydrologic Soil Group: A Ecological site: R067BY036CO - Overflow Hydric soil rating: No Minor Components Caruso Percent of map unit:6 percent Ecological site:R067BY036CO - Overflow Hydric soil rating: No Table mountain Percent of map unit:6 percent Ecological site:R067BY036CO - Overflow Hydric soil rating: No Fluvaquentic haplustolls Percent of map unit:3 percent Landform:Terraces Hydric soil rating: Yes 105—Table Mountain loam, 0 to 1 percent slopes Map Unit Setting National map unit symbol: jpty Elevation: 4,800 to 5,600 feet Mean annual precipitation: 13 to 15 inches Mean annual air temperature: 48 to 50 degrees F Frost-free period: 135 to 150 days Farmland classification: Prime farmland if irrigated Map Unit Composition Table mountain and similar soils:85 percent Minor components:15 percent Estimates are based on observations, descriptions, and transects of the mapunit. Custom Soil Resource Report 15 Description of Table Mountain Setting Landform:Stream terraces, flood plains Landform position (three-dimensional):Tread Down-slope shape:Linear Across-slope shape:Linear Parent material:Alluvium Typical profile H1 - 0 to 36 inches: loam H2 - 36 to 60 inches: clay loam Properties and qualities Slope:0 to 1 percent Depth to restrictive feature:More than 80 inches Drainage class:Well drained Runoff class: Low Capacity of the most limiting layer to transmit water (Ksat):Moderately high to high (0.60 to 2.00 in/hr) Depth to water table:More than 80 inches Frequency of flooding:None Frequency of ponding:None Calcium carbonate, maximum content:15 percent Maximum salinity:Nonsaline to very slightly saline (0.0 to 2.0 mmhos/cm) Sodium adsorption ratio, maximum:5.0 Available water supply, 0 to 60 inches: High (about 9.8 inches) Interpretive groups Land capability classification (irrigated): 1 Land capability classification (nonirrigated): 3c Hydrologic Soil Group: B Ecological site: R049XY036CO - Overflow Hydric soil rating: No Minor Components Caruso Percent of map unit:7 percent Hydric soil rating: No Fluvaquentic haplustolls Percent of map unit:4 percent Landform:Terraces Hydric soil rating: Yes Paoli Percent of map unit:4 percent Hydric soil rating: No Custom Soil Resource Report 16 Soil Information for All Uses Soil Properties and Qualities The Soil Properties and Qualities section includes various soil properties and qualities displayed as thematic maps with a summary table for the soil map units in the selected area of interest. A single value or rating for each map unit is generated by aggregating the interpretive ratings of individual map unit components. This aggregation process is defined for each property or quality. Soil Qualities and Features Soil qualities are behavior and performance attributes that are not directly measured, but are inferred from observations of dynamic conditions and from soil properties. Example soil qualities include natural drainage, and frost action. Soil features are attributes that are not directly part of the soil. Example soil features include slope and depth to restrictive layer. These features can greatly impact the use and management of the soil. Hydrologic Soil Group Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. 17 Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Custom Soil Resource Report 18 19 Custom Soil Resource Report Map—Hydrologic Soil Group 4493890449392044939504493980449401044940404494070449410044938904493920449395044939804494010449404044940704494100493480 493510 493540 493570 493600 493630 493660 493690 493720 493750 493780 493810 493480 493510 493540 493570 493600 493630 493660 493690 493720 493750 493780 493810 40° 35' 51'' N 105° 4' 37'' W40° 35' 51'' N105° 4' 23'' W40° 35' 44'' N 105° 4' 37'' W40° 35' 44'' N 105° 4' 23'' WN Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 13N WGS84 0 50 100 200 300Feet 0 20 40 80 120Meters Map Scale: 1:1,530 if printed on A landscape (11" x 8.5") sheet. Soil Map may not be valid at this scale. MAP LEGEND MAP INFORMATION Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons A A/D B B/D C C/D D Not rated or not available Soil Rating Lines A A/D B B/D C C/D D Not rated or not available Soil Rating Points A A/D B B/D C C/D D Not rated or not available Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:24,000. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:3857) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Larimer County Area, Colorado Survey Area Data: Version 16, Sep 2, 2021 Soil map units are labeled (as space allows) for map scales 1:50,000 or larger. Date(s) aerial images were photographed: Aug 11, 2018—Aug 12, 2018 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Custom Soil Resource Report 20 Table—Hydrologic Soil Group Map unit symbol Map unit name Rating Acres in AOI Percent of AOI 73 Nunn clay loam, 0 to 1 percent slopes C 3.0 30.5% 81 Paoli fine sandy loam, 0 to 1 percent slopes A 0.9 8.8% 105 Table Mountain loam, 0 to 1 percent slopes B 6.0 60.7% Totals for Area of Interest 9.8 100.0% Rating Options—Hydrologic Soil Group Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Custom Soil Resource Report 21 References American Association of State Highway and Transportation Officials (AASHTO). 2004. Standard specifications for transportation materials and methods of sampling and testing. 24th edition. American Society for Testing and Materials (ASTM). 2005. Standard classification of soils for engineering purposes. ASTM Standard D2487-00. Cowardin, L.M., V. Carter, F.C. Golet, and E.T. LaRoe. 1979. Classification of wetlands and deep-water habitats of the United States. U.S. Fish and Wildlife Service FWS/OBS-79/31. Federal Register. July 13, 1994. Changes in hydric soils of the United States. Federal Register. September 18, 2002. Hydric soils of the United States. Hurt, G.W., and L.M. Vasilas, editors. Version 6.0, 2006. Field indicators of hydric soils in the United States. National Research Council. 1995. Wetlands: Characteristics and boundaries. Soil Survey Division Staff. 1993. Soil survey manual. Soil Conservation Service. U.S. Department of Agriculture Handbook 18. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/national/soils/?cid=nrcs142p2_054262 Soil Survey Staff. 1999. Soil taxonomy: A basic system of soil classification for making and interpreting soil surveys. 2nd edition. Natural Resources Conservation Service, U.S. Department of Agriculture Handbook 436. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053577 Soil Survey Staff. 2010. Keys to soil taxonomy. 11th edition. U.S. Department of Agriculture, Natural Resources Conservation Service. http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/?cid=nrcs142p2_053580 Tiner, R.W., Jr. 1985. Wetlands of Delaware. U.S. Fish and Wildlife Service and Delaware Department of Natural Resources and Environmental Control, Wetlands Section. United States Army Corps of Engineers, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Waterways Experiment Station Technical Report Y-87-1. United States Department of Agriculture, Natural Resources Conservation Service. National forestry manual. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ home/?cid=nrcs142p2_053374 United States Department of Agriculture, Natural Resources Conservation Service. National range and pasture handbook. http://www.nrcs.usda.gov/wps/portal/nrcs/ detail/national/landuse/rangepasture/?cid=stelprdb1043084 22 United States Department of Agriculture, Natural Resources Conservation Service. National soil survey handbook, title 430-VI. http://www.nrcs.usda.gov/wps/portal/ nrcs/detail/soils/scientists/?cid=nrcs142p2_054242 United States Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. U.S. Department of Agriculture Handbook 296. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/national/soils/? cid=nrcs142p2_053624 United States Department of Agriculture, Soil Conservation Service. 1961. Land capability classification. U.S. Department of Agriculture Handbook 210. http:// www.nrcs.usda.gov/Internet/FSE_DOCUMENTS/nrcs142p2_052290.pdf Custom Soil Resource Report 23 NORTHERNENGINEERING.COM | 970.221.4158 PRELIMINARY DRAINAGE REPORT: Powerhouse II FORT COLLINS | GREELEY APPENDIX MAP POCKET EXHIBITS AS LISTED ON TABLE OF CONTENTS EAST VINE DRIVENORTH COLLEGE AVENUE LAKE CANALTVAULTF.O.VAULTF.O.F.O.CONTROLIRR CONTROLIRR GAS/ / / / / / / // / / / / / / /GASLOT 1BRUSH MOBILEHOME P.U.D.(740 N. COLLEGE)LOT 3BRUSH MOBILEHOME P.U.D.(108 E. VINE)LOT 2BRUSH MOBILEHOME P.U.D.(704 N. COLLEGE)LOT 4(202 E. VINE)EAST VINE DRIVENORTH COLLEGE AVENUE LAKE CANALTVAULTF.O .VAULTF.O.F.O.CONTROLIRR CONTROLIRR GAS/ / / / / / / // / / / / / / /GASLOT 1BRUSH MOBILEHOME P.U.D.(740 N. COLLEGE)TFTFLOT 3BRUSH MOBILEHOME P.U.D.(108 E. VINE)LOT 2BRUSH MOBILEHOME P.U.D.(704 N. COLLEGE)LOT 4(202 E. VINE)ROOFTOPCONCRETEASPHALTPAVERSSURFACEAREA (SF)% IMPERV.IMPERV.AREA (SF)8,9255,04843,18809010010040TOTALS201,281109,526TOTAL=EXISTINGP:\207-030\DWG\DRNG\207-030_DRNG-IMP.DWG POWERHOUSE 2FORT COLLINS COLORADODESCRIPTIONEXISTING VS. PROPOSEDIMPERVIOUS AREA - BASIN ADRAWN BYC. ORTIZDATEJUNE 29th, 2022PROJECT207-030DR-ADRAWINGSCALE1"=100'GRAVEL133,1454053,258LANDSCAPE10,975008,0335,04843,1880TOTAL PERCENT IMPERVIOUS = 54%PROPOSEDROOFTOPCONCRETEPAVERSGRAVELSURFACEAREA (SF)% IMPERV.IMPERV.AREA (SF)TOTALS206,172114,855TOTAL=LANDSCAPEASPHALT39,028 35,93833,4146,44690%100%100%40%12,93440%5,17371,8460% 035,12535,93833,4142,578TOTAL PERCENT IMPERVIOUS = 56%GRAVEL W/ SOLAR6,56740%2,627STORMWATER RATE FACTOR TABLEPremiseAddressSURFACEAREA (SF)% IMPERV.IMPER.AREA (SF)Lot 2 704 N. COLLEGE37,7380 -Lot 3 108 E. VINE12,88095 12,236Lot 4 202 E. VINE 166,00660 99,604 216,62452 111,840 DVAULTCABLEDDDSTTVAULTF.O.VAULTF.O.F.O.DCONTROLIRRCONTROLIRR GASXXOHU OHU OHUD FESLIDMH/ / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / /FESFESFESSTSTSTGASDTFTFGUGEUGEUDUDUDUDUDUDUDS11VINE DRIVECOLLEGE AVENUE JEROME STREET JEROME STREET LLC,216 E OAK STJEROME STREET STATION LLC,742 N COLLEGE AVELMC VENTURES LLC,742 N COLLEGE AVECITY OF FORT COLLINS405 N COLLEGE AVEMORAK KAREN LLC622 N COLLEGE AVECITY OF FORT COLLINS,740 N COLLEGE AVEFORT COLLINS1432568101112co1w8w10w1179PROPERTYBOUNDARYPROPERTYBOUNDARYPROPOSED STORM LINESOUTH RAIN GARDENWQ1 - OUTLETSTRUCTUREPROPOSEDSTORM LINEEXISTINGSTORM LINEPROPOSEDSTORM LINEPROPOSEDSTORM LINEPROPOSEDSTORM LINEPROPOSEDSTORM LINEPROPOSEDSTORM LINEPROPOSED STORMINLET (TYP.)PROPOSED STORMINLET (TYP.)SOUTH RAIN GARDENNORTH RAIN GARDENDETENTION POND 1WQCV VOLUME = 0.03 AC-FTTOTAL VOLUME REQUIRED = 0.32 AC-FTMAXIMUM RELEASE RATE = 8.50 CFSOUTLET IN. EL. = 4957.00WQCV WATER SURFACE EL. = 4957.74100-YR. WATER SURFACE EL. = 4959.52FREEBOARD = 0.48 FTTOP OF BERM EL. = 4960.00EXISTINGINLET12.23 ac20.74 ac60.41 ac30.72 acW80.63 ac120.14 ac90.14 ac110.05 acCo10.42 ac80.11 ac100.03 ac40.11 ac50.14 ac70.04 acW101.50 acW110.89 acSOUTH RAIN GARDENEXISTINGSTORM LINEEXISTINGINLET100 YR FLOOD PLAIN(CURRENT EFFECTIVE)500 YR FLOOD PLAIN(CURRENT EFFECTIVE)100 YR FLOOD PLAIN(CURRENT EFFECTIVE)100 YR FLOOD PLAIN(CURRENT EFFECTIVE)500 YR FLOOD PLAIN(CURRENT EFFECTIVE)100 YR FLOOD PLAIN(CURRENT EFFECTIVE)500 YR FLOOD PLAIN(CURRENT EFFECTIVE)100 YR FLOOD PLAIN(CURRENT EFFECTIVE)500 YR FLOOD PLAIN(CURRENT EFFECTIVE)100 YR FLOOD PLAIN(CURRENT EFFECTIVE)SheetPOWERHOUSE 2 NOT FOR CONSTR U C T I O NREVIEW SET of 16( IN FEET )1 inch = ft.Feet05050501001501. REFER TO THE PRELIMINARY DRAINAGE REPORT, DATED JUNE 29, 2022 FORADDITIONAL INFORMATION.2. PORTIONS OF THIS PROPERTY ARE LOCATED IN THE FEMA REGULATED, 100YEAR AND 500 YEAR POUDRE RIVER FLOODPLAIN. ANY DEVELOPMENT WITHINTHE FLOODPLAIN MUST COMPLY WITH THE SAFETY REGULATIONS OF CHAPTER10 OF CITY MUNICIPAL CODE.3. ANY CONSTRUCTION ACTIVITIES IN THE FLOOD FRINGE (E.G. STRUCTURES,SIDEWALK OR CURB & GUTTER INSTALLATION/REPLACEMENT, UTILITY WORK,LANDSCAPING, ETC.) MUST BE PRECEDED BY AN APPROVED FLOODPLAIN USEPERMIT, THE APPROPRIATE PERMIT APPLICATION FEES, AND APPROVED PLANS.4. CONSTRUCTION OF RESIDENTIAL AND/OR MIXED_USE STRUCTURES ISPROHIBITED IN THE POUDRE RIVER 100_YEAR FLOODPLAIN.5. OUTSIDE STORAGE OF EQUIPMENT OR FLOATABLE MATERIALS WHETHERPERMANENT OR TEMPORARY IS PROHIBITED IN THE 100_YEAR FLOODPLAIN.6. AT_RISK POPULATIONS, ESSENTIAL SERVICES, HAZARDOUS MATERIALS, ANDGOVERNMENT SERVICES CRITICAL FACILITIES ARE PROHIBITED IN THE 100_YEARFLOODPLAIN.7. THE APPLICANT ACKNOWLEDGES THAT THIS SITE DEVELOPMENT PLAN DOESNOT COMPLY WITH THE CURRENT REGULATORY FLOODPLAIN. PERMITS CANNOTBE ISSUED FOR RESIDENTIAL STRUCTURES IN THE REGULATORY FLOODPLAINUNTIL A LOMR IS APPROVED THROUGH FEMA. IT IS AT OUR OWN RISK THAT WECONTINUE THROUGH THE PLANNING PROCESSDR1DRAINAGE EXHIBIT15 NORTHSWALE SECTIONSSWALE SUMMARY TABLESWALE IDMIN D MIN TWS1 (n:1) S2 (n:1)Q1 - 10.79 11.45 3.7 10.8 11.20PROPOSED CONTOURPROPOSED STORM SEWERPROPOSED SWALEEXISTING CONTOURPROPOSED CURB & GUTTERPROPERTY BOUNDARYPROPOSED INLETADESIGN POINTFLOW ARROWDRAINAGE BASIN LABELDRAINAGE BASIN BOUNDARYPROPOSED SWALE SECTION11NOTES:ALEGEND:CALL 2 BUSINESS DAYS IN ADVANCE BEFORE YOUDIG, GRADE, OR EXCAVATE FOR THE MARKING OFUNDERGROUND MEMBER UTILITIES.CALL UTILITY NOTIFICATION CENTER OFCOLORADOKnow what'sbelow.before you dig.CallRC2 C100Q2(cfs)Q100(cfs)