Loading...
HomeMy WebLinkAboutFORTY-THREE PRIME - FDP210019 - SUBMITTAL DOCUMENTS - ROUND 1 - DRAINAGE REPORT July 28, 2021 FINAL DRAINAGE LETTER AND LID REPORT FORTY-THREE PRIME Fort Collins, Colorado Prepared for: Harvest Land Company 855 Norway Maple Drive Loveland, Colorado 80538 Prepared by: 301 North Mason Street, Suite 100 Fort Collins, Colorado 80524 Phone: 970.221.4158 www.northernengineering.com Project Number: 1328-010 Drainage Letter and LID Report – Forty-Three Prime Date: July 28, 2021 Project: Forty-Three Prime Project No. 1328-010 Final Development Plan (FDP) Fort Collins, Colorado Attn: City of Fort Collins Stormwater Utility 700 Wood Street Fort Collins, Colorado 80521 To whom it may concern: This letter serves to address the stormwater impacts of the proposed project known as “Forty-Three Prime”. The site is in southeast Fort Collins and is bounded to the north by East Trilby Road, to the east by Brittany Drive, to the south by Candlewood Drive and to the west by Autumn Ridge Drive. The project site is Tract A of the Provincetowne P.U.D. Filing 2, which was approved in 2001, and was included in the drainage study by Manhard Consulting for that project. The proposed development consists of six (6) multifamily buildings, a parking area, two carports and amenity areas for residents. The project site also contains a detention area and drainage facilities that were designed and constructed as a part of the Provincetowne development. Since the project was included in the Provincetowne development, this letter is intended to show conformance with the approved drainage design, including general drainage patterns and imperviousness. This letter also documents how the project meets new Low Impact Development requirements that the City of Fort Collins has implemented since the original project was approved. Original Drainage Patterns The original Provincetowne drainage design divided Tract A into 5 basins – Basins 212, 220, 221, 225 and 406. In general, all of the basins drained from south to north, where they were intercepted by a swale along the north boundary. The exception was Basin 212, which drained west to Autumn Ridge Drive and then collected by an inlet located on Trilby. Once captured, the flows from all of the basins were conveyed to the northeast corner of Tract A and detained in Detention Pond 306. An Existing Drainage Exhibit has been provided at the back of this report for reference, along with excerpts from the original report in the appendix. Proposed Drainage Patterns The Forty-Three Prime project has divided the site into seven drainage basins that follow essentially the same drainage patterns originally approved with the Provincetowne project. The proposed site is comprised of Basin A, which encompasses the parking area, and Basins B1-B3, which define building and landscape areas. Basin C encompasses areas outside of the main development, including the existing detention pond and the swale along the north property line. All of the aforementioned basins drain to the existing detention pond via swales and surface conveyance. Additionally, Basin OS1 is defined on the west side of the project to quantify flows to Autumn Ridge Drive captured by the existing inlet located on Trilby and conveyed to the existing detention pond via existing storm drains. Please see the Drainage Exhibit for more information. Page | 3 Site Imperviousness While the drainage patterns of the proposed project generally conform with the previously appr oved drainage design, the drainage basins themselves do not have the same extents or areas. Since a direct comparison cannot be made between the original and proposed basins, a weighted percent imperviousness was developed. Using this approach, we find the original drainage plan had a Composite Percent Imperviousness of 42.6% (C100=0.56) while the proposed project will have a Composite Percent Imperviousness of 39.5% (C100=0.44). This is an overall imperviousness decrease of 3.1%, which will result in decreased runoff from the project than the original report anticipated. Detention As shown in the analysis of overall Site Imperviousness, the proposed project will decrease the imperviousness of the project site when compared to the originally approved project, thereby decreasing the runoff from the project site. This decrease in imperviousness and runoff also results in a decrease in the required detention volume identified in the original Provincetowne report. Since detention was accounted for in the original drainage report and the detention required by this project is less than originally assumed, no additional detention is required as a part of this project, and no changes to the existing facilities are proposed. Inlets Similar to the analysis performed for detention, all areas draining to existing inlets have a decrease in imperviousness and area from what was projected in the original Provincetowne report. This results in decreased runoff to the existing inlets that were designed and approved with the earlier project, so no additional inlet calculations from the proposed infrastructure is provided as a part of this report. Water Quality/LID Conformance Although stormwater quantity detention is not required, stormwater quality will be addressed by permanent Best Management Practices (BMPs) and Low Impact Development (LID) requirements. City LID requirements specify that either 75% of all newly added impermeable areas receive water quality treatment from a LID facility OR 50% of new pavements be treated by a LID methoud along with 25% of drivable surfaces being permeable pavers. This project proposes to treat at least 75% of the new impervious areas through a combination of a large rain garden on the east side of the project site. The large rain garden will treat 76,305 square-feet of impervious area on the site. This is 85.66% of the total impervious area within the project area, which exceeds the amount of LID treatment required by City Code. The rain garden will be designed as a single feature that will treat the majority of the parking lot, concrete flatwork and rooftops by conveying flows from the parking area into the rain garden. The facility will have 12” of ponding, at which point stormwater will flow out the east side of the facility, down a reinforced rundown and into the existing detention pond. A LID Treatment Exhibit is provided with this report detailing the treatment areas and methods. Page | 4 Erosion and Sediment Control During construction, the Contractor will follow the appropriate and applicable City of Fort Collins standards for erosion and sediment control. Since more than 10,000 sf will be disturbed as a part of this project, a comprehensive Stormwater Management Plan will be prepared for this project at final design. Post construction water quality and erosion control will be achieved by a fully established and stabilized site. All areas disturbed during construction will receive permanent hardscape, landscape, or building structure. Floodplains There are no regulatory floodplains associated with the project. Conclusions The proposed grading concept closely matches the original drainage patterns and decreases overall site imperviousness and additional detention is proven to be unnecessary. Stormwater quality has been provided and meets the city requirements for Low Impact Development treatment. Therefore, it is my professional opinion that Forty-Three Prime satisfies all applicable stormwater criteria and will effectively limit potential damage associated with its stormwater runoff. Please do not hesitate to contact me if you have questions or require additional information. Sincerely, Frederick S. Wegert, PE Project Engineer ATTACHMENT 1 HYDROLOGIC CALCULATIONS FORT COLLINS STORMWATER CRITERIA MANUAL Hydrology Standards (Ch. 5) 3.0 Rational Method 3.4 Intensity-Duration-Frequency Curves for Rational Method Page 8 Table 3.4-1. IDF Table for Rational Method Duration (min) Intensity 2-year (in/hr) Intensity 10-year (in/hr) Intensity 100-year (in/hr) Duration (min) Intensity 2-year (in/hr) Intensity 10-year (in/hr) Intensity 100-year (in/hr) 5 2.85 4.87 9.95 39 1.09 1.86 3.8 6 2.67 4.56 9.31 40 1.07 1.83 3.74 7 2.52 4.31 8.80 41 1.05 1.80 3.68 8 2.40 4.10 8.38 42 1.04 1.77 3.62 9 2.30 3.93 8.03 43 1.02 1.74 3.56 10 2.21 3.78 7.72 44 1.01 1.72 3.51 11 2.13 3.63 7.42 45 0.99 1.69 3.46 12 2.05 3.50 7.16 46 0.98 1.67 3.41 13 1.98 3.39 6.92 47 0.96 1.64 3.36 14 1.92 3.29 6.71 48 0.95 1.62 3.31 15 1.87 3.19 6.52 49 0.94 1.6 3.27 16 1.81 3.08 6.30 50 0.92 1.58 3.23 17 1.75 2.99 6.10 51 0.91 1.56 3.18 18 1.70 2.90 5.92 52 0.9 1.54 3.14 19 1.65 2.82 5.75 53 0.89 1.52 3.10 20 1.61 2.74 5.60 54 0.88 1.50 3.07 21 1.56 2.67 5.46 55 0.87 1.48 3.03 22 1.53 2.61 5.32 56 0.86 1.47 2.99 23 1.49 2.55 5.20 57 0.85 1.45 2.96 24 1.46 2.49 5.09 58 0.84 1.43 2.92 25 1.43 2.44 4.98 59 0.83 1.42 2.89 26 1.4 2.39 4.87 60 0.82 1.4 2.86 27 1.37 2.34 4.78 65 0.78 1.32 2.71 28 1.34 2.29 4.69 70 0.73 1.25 2.59 29 1.32 2.25 4.60 75 0.70 1.19 2.48 30 1.30 2.21 4.52 80 0.66 1.14 2.38 31 1.27 2.16 4.42 85 0.64 1.09 2.29 32 1.24 2.12 4.33 90 0.61 1.05 2.21 33 1.22 2.08 4.24 95 0.58 1.01 2.13 34 1.19 2.04 4.16 100 0.56 0.97 2.06 35 1.17 2.00 4.08 105 0.54 0.94 2.00 36 1.15 1.96 4.01 110 0.52 0.91 1.94 37 1.16 1.93 3.93 115 0.51 0.88 1.88 38 1.11 1.89 3.87 120 0.49 0.86 1.84 FORT COLLINS STORMWATER CRITERIA MANUAL Hydrology Standards (Ch. 5) 3.0 Rational Method 3.4 Intensity-Duration-Frequency Curves for Rational Method Page 9 Figure 3.4-1. Rainfall IDF Curve – Fort Collins SITE IMPERVIOUSNESS COMPARISON Basin ID Basin Area (ac)Composite % Imperv. 100-year Composite Runoff Coefficient 212 0.68 33%0.71 220 0.52 45%0.74 221 2.18 45%0.74 224 0.08 96%1.00 225 1.30 39%0.73 406 0.11 45%0.74 Total Site 4.87 42.6%0.56 Basin ID Basin Area (ac)Composite % Imperv. 100-year Composite Runoff Coefficient OS1 0.23 40%0.69 A 1.64 79%1.00 B1 0.15 68%0.98 B2 0.03 59%0.89 B3 0.15 39%0.69 B4 0.45 39%0.70 C 2.21 8%0.39 Total Site 4.87 39.7%0.44 EXISTING MASTER PLANNED COMPOSITE % IMPERVIOUSNESS PROPOSED COMPOSITE % IMPERVIOUSNESS CHARACTER OF SURFACE: Runoff Coefficient Percentage Impervious Project:Forty-Three Prime Streets, Parking Lots, Roofs, Alleys, and Drives:Calculations By:F. Wegert Asphalt ……....……………...……….....…...……………….…………………………………..0.95 100%Date: Concrete …….......……………….….……….………………..….…………………………………0.95 90% Gravel ……….…………………….….…………………………..………………………………..0.50 40% Roofs …….…….………………..……………….…………………………………………….. 0.95 90% Pavers…………………………...………………..……………………………………………..0.50 40% Lawns and Landscaping Sandy Soil ……..……………..……………….……………………………………………..0.15 0% Clayey Soil ….….………….…….…………..……………………………………………….0.25 0%2-year Cf = 1.00 100-year Cf = 1.25 Basin ID Basin Area (ac) Area of Asphalt (ac) Area of Concrete (ac) Area of Roofs (ac) Area of Gravel (ac) Area of Pavers (ac) Area of Lawns and Landscaping (ac) 2-year Composite Runoff Coefficient 10-year Composite Runoff Coefficient 100-year Composite Runoff Coefficient Composite % Imperv. OS1 0.23 0.04 0.03 0.03 0.00 0.00 0.13 0.55 0.55 0.69 40% A 1.64 0.75 0.38 0.23 0.00 0.00 0.28 0.83 0.83 1.00 79% B1 0.15 0.00 0.01 0.11 0.00 0.00 0.04 0.78 0.78 0.98 68% B2 0.03 0.00 0.00 0.02 0.00 0.00 0.01 0.71 0.71 0.89 59% B3 0.15 0.00 0.01 0.05 0.00 0.00 0.09 0.55 0.55 0.69 39% B4 0.45 0.00 0.03 0.17 0.00 0.00 0.25 0.56 0.56 0.70 39% C 2.21 0.00 0.07 0.12 0.02 0.00 2.01 0.31 0.31 0.39 8% Rain Garden 2.42 0.75 0.43 0.58 0.00 0.00 0.66 0.76 0.76 0.95 68% DEVELOPED COMPOSITE % IMPERVIOUSNESS AND RUNOFF COEFFICIENT CALCULATIONS Runoff Coefficients are taken from the City of Fort Collins Storm Drainage Design Criteria and Construction Standards, Table 3-3. % Impervious taken from UDFCD USDCM, Volume I. 10-year Cf = 1.00 July 28, 2021 Overland Flow, Time of Concentration: Project:Forty-Three Prime Calculations By: Date: Gutter/Swale Flow, Time of Concentration: Tt = L / 60V Tc = Ti + Tt (Equation RO-2) Velocity (Gutter Flow), V = 20·S½ Velocity (Swale Flow), V = 15·S½ NOTE: C-value for overland flows over grassy surfaces; C = 0.25 Is Length >500' ? C*Cf (2-yr Cf=1.00) C*Cf (10-yr Cf=1.00) C*Cf (100-yr Cf=1.25) Length, L (ft) Slope, S (%) Ti 2-yr (min) Ti 10-yr (min) Ti 100-yr (min) Length, L (ft) Slope, S (%) Velocity, V (ft/s) Tt (min) Length, L (ft) Slope, S (%) Velocity, V (ft/s) Tt (min) 2-yr Tc (min) 10-yr Tc (min) 100-yr Tc (min) OS1 OS1 No 0.25 0.25 0.31 0 N/A N/A N/A N/A 99 4.88% 4.42 0.4 0 NA N/A N/A 5 5 5 A A No 0.25 0.25 0.31 23 22.78% 2.7 2.7 2.5 563 0.50% 1.41 6.6 91 1.79%2.01 0.8 10 10 10 B1 B1 No 0.25 0.25 0.31 0 N/A N/A N/A N/A 143 0.50% 1.41 1.7 21 2.00% 2.12 0.2 5 5 5 B2 B2 No 0.25 0.25 0.31 0 N/A N/A N/A N/A 61 0.50% 1.41 0.7 20 4.85% 3.30 0.1 5 5 5 B3 B3 No 0.25 0.25 0.31 53 6.64% 6.2 6.2 5.7 138 0.50% 1.41 1.6 76 1.96% 2.10 0.6 8 8 8 B4 B4 No 0.25 0.25 0.31 23 22.78% 2.7 2.7 2.5 563 0.50% 1.41 6.6 91 1.79%2.01 0.8 10 10 10 C C No 0.25 0.25 0.31 140 0.91%19.4 19.4 17.9 513 0.40%1.26 6.8 0 NA N/A N/A 26 26 25 DEVELOPED TIME OF CONCENTRATION COMPUTATIONS Gutter Flow Swale Flow Design Point Basin Overland Flow F. Wegert July 28, 2021 Time of Concentration (Equation RO-4) () 3 1 *1.187.1 S LCfCTi -= Rational Method Equation:Project:Forty-Three Prime Calculations By: Date: From Section 3.2.1 of the CFCSDDC Rainfall Intensity: Design Point Basin(s)Area, A (acres) 2-yr Tc (min) 10-yr Tc (min) 100-yr Tc (min) C2 C10 C100 Intensity, i2 (in/hr) Intensity, i10 (in/hr) Intensity, i100 (in/hr) Flow, Q2 (cfs) Flow, Q10 (cfs) Flow, Q100 (cfs) Flow, WQ (cfs) OS1 OS1 0.23 5 5 5 0.55 0.55 0.69 2.85 4.87 9.95 0.4 0.6 1.6 0.18 A A 1.64 10 10 10 0.83 0.83 1.00 2.21 3.78 7.88 3.0 5.1 12.9 1.50 B1 B1 0.15 5 5 5 0.78 0.78 0.98 2.85 4.87 9.95 0.3 0.6 1.5 0.17 B2 B2 0.03 5 5 5 0.71 0.71 0.89 2.85 4.87 9.95 0.1 0.1 0.2 0.03 B3 B3 0.15 8 8 8 0.55 0.55 0.69 2.40 4.10 8.59 0.2 0.4 0.9 0.10 B4 B4 0.45 10 10 10 0.56 0.56 0.70 2.21 3.78 7.88 0.6 0.9 2.5 0.28 C C 2.21 26 26 25 0.31 0.31 0.39 1.40 2.39 5.04 1.0 1.7 4.4 0.48 DEVELOPED RUNOFF COMPUTATIONS F. Wegert July 28, 2021 Rainfall Intensity taken from the City of Fort Collins Storm Drainage Design Criteria (CFCSDDC), Figure 3.1 ()()()AiCCQf= ATTACHMENT 2 HYDRAULIC CALCULATIONS Project #: Project Name: Project Loc.: Design Flowrate Allowable Flowrate1 Overflow Design Flowrate Allowable Flowrate1 Overflow Inlet A2-1 Basin B2 8" Drain Basin 0.10 cfs 0.54 cfs 0.00 cfs 0.20 cfs 0.54 cfs 0.00 cfs Inlet A4 1/2 of Basin B3 15" Drain Basin 0.10 cfs 0.69 cfs 0.00 cfs 0.45 cfs 0.69 cfs 0.00 cfs Inlet A6-1 1/4 of Basin B3 8" Drain Basin 0.05 cfs 0.62 cfs 0.00 cfs 0.23 cfs 0.62 cfs 0.00 cfs Inlet A6-2 1/4 of Basin B3 8" Drain Basin 0.05 cfs 0.66 cfs 0.00 cfs 0.23 cfs 0.66 cfs 0.00 cfs Inlet A7-1-1 185 sq. ft. of landscaping in Basin B4 8" Drain Basin 0.01 cfs 0.44 cfs 0.00 cfs 0.05 cfs 0.44 cfs 0.00 cfs Inlet A7-1-2 340 sq. ft. of landscaping in Basin B4 8" Drain Basin 0.01 cfs 0.69 cfs 0.00 cfs 0.05 cfs 0.69 cfs 0.00 cfs Inlet A7-2 1/6 of Basin B4 8" Drain Basin 0.10 cfs 0.55 cfs 0.00 cfs 0.42 cfs 0.55 cfs 0.00 cfs Inlet A7-3 1/6 of Basin B4 8" Drain Basin 0.10 cfs 1.17 cfs 0.00 cfs 0.42 cfs 1.17 cfs 0.00 cfs Inlet A8 1/3 of Basin B4 12" Drain Basin 0.20 cfs 1.07 cfs 0.00 cfs 0.83 cfs 1.07 cfs 0.00 cfs Inlet A11 1/3 of Basin B4 12" Drain Basin 0.20 cfs 1.52 cfs 0.00 cfs 0.83 cfs 1.52 cfs 0.00 cfs Inlet B4 1/3 of Basin B1 12" Drain Basin 0.10 cfs 0.75 cfs 0.00 cfs 0.50 cfs 0.75 cfs 0.00 cfs Inlet B5 1/6 of Basin B1 8" Drain Basin 0.05 cfs 0.63 cfs 0.00 cfs 0.25 cfs 0.63 cfs 0.00 cfs Inlet B6 1/6 of Basin B1 8" Drain Basin 0.05 cfs 0.64 cfs 0.00 cfs 0.25 cfs 0.64 cfs 0.00 cfs Inlet B6-1 235 sq. ft. of landscaping in Basin A 8" Drain Basin 0.01 cfs 0.10 cfs 0.00 cfs 0.05 cfs 0.10 cfs 0.00 cfs Inlet B7 1/3 of Basin B1 8" Drain Basin 0.10 cfs 0.64 cfs 0.00 cfs 0.50 cfs 0.64 cfs 0.00 cfs Inlet C1 1/3 of Basin B2 8" Drain Basin 0.17 cfs 0.94 cfs 0.00 cfs 0.73 cfs 0.94 cfs 0.00 cfs Inlet C2 1/3 of Basin B3 8" Drain Basin 0.17 cfs 1.12 cfs 0.00 cfs 0.73 cfs 1.12 cfs 0.00 cfs Inlet C3 1/3 of Basin B4 8" Drain Basin 0.17 cfs 1.33 cfs 0.00 cfs 0.73 cfs 1.33 cfs 0.00 cfs 1328-010 Forty-Three Prime Fort Collins, Colorado INLET CAPACITIES SUMMARY Private Area Drains and Pond Outlets Inlet Type2 Inlet and Area Drain Capacities 2-Year 100-Year Basins / Design Notes Notes: 1) Allowable flowrate calculated per Urban Drainage Inlet 5.01. 2) Drain basins are assumed to be a Nyloplast Drain Basin. Inlet Name:Inlet A2-1 Project: 10-Year Design Flow (cfs)0.10 Location: 100-Year Design Flow (cfs)0.20 Calc. By: Type of Grate:0.35 Diameter of Grate (ft):0.67 4,962.56 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,962.56 0.00 0.00 0.00 0.10 4,962.66 0.10 0.30 0.10 10-Year Storm 0.16 4,962.72 0.20 0.38 0.20 100-Year Storm 0.20 4,962.76 0.28 0.42 0.28 0.30 4,962.86 0.52 0.51 0.51 0.33 4,962.89 0.60 0.54 0.54 Overflow to the east 0.40 4,962.96 0.79 0.59 0.59 0.50 4,963.06 1.11 0.66 0.66 0.60 4,963.16 1.46 0.73 0.73 0.70 4,963.26 1.84 0.78 0.78 0.80 4,963.36 2.25 0.84 0.84 0.83 4,963.39 2.38 0.85 0.85 FG at Building AREA INLET PERFORMANCE CURVE Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Rim Elevation (ft): Open Area of Grate (ft2): Depth vs. Flow Nyloplast 8" Dome 1328-010 Forty-Three Prime F. Wegert Reduction Factor: 0.00 0.50 1.00 1.50 2.00 2.50 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet A4 Project: 10-Year Design Flow (cfs)0.20 Location: 100-Year Design Flow (cfs)0.45 Calc. By: Type of Grate:1.23 Diameter of Grate (ft):1.25 4,962.41 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,962.41 0.00 0.00 0.00 0.10 4,962.51 0.19 1.04 0.19 0.11 4,962.52 0.21 1.09 0.21 10-Year Storm 0.18 4,962.59 0.45 1.40 0.45 100-Year Storm 0.20 4,962.61 0.53 1.47 0.53 0.30 4,962.71 0.97 1.81 0.97 0.40 4,962.81 1.49 2.09 1.49 0.50 4,962.91 2.08 2.33 2.08 0.54 4,962.95 2.34 2.42 2.34 Overflow to the east 0.60 4,963.01 2.74 2.55 2.55 0.70 4,963.11 3.45 2.76 2.76 0.98 4,963.39 5.71 3.26 3.26 FG at Building Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 15" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 0.00 0.20 0.40 0.60 0.80 1.00 1.20Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet A6-1 Project: 10-Year Design Flow (cfs)0.10 Location: 100-Year Design Flow (cfs)0.23 Calc. By: Type of Grate:0.35 Diameter of Grate (ft):0.67 4,962.48 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,962.48 0.00 0.00 0.00 0.10 4,962.58 0.10 0.30 0.10 10-Year Storm 0.18 4,962.66 0.24 0.40 0.24 100-Year Storm 0.20 4,962.68 0.28 0.42 0.28 0.30 4,962.78 0.52 0.51 0.51 0.40 4,962.88 0.79 0.59 0.59 0.43 4,962.91 0.89 0.62 0.62 Overflow to Inlet 6-2 0.50 4,962.98 1.11 0.66 0.66 0.60 4,963.08 1.46 0.73 0.73 0.70 4,963.18 1.84 0.78 0.78 0.80 4,963.28 2.25 0.84 0.84 0.91 4,963.39 2.73 0.89 0.89 FG at Building Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 8" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 0.50 1.00 1.50 2.00 2.50 3.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet A6-2 Project: 10-Year Design Flow (cfs)0.10 Location: 100-Year Design Flow (cfs)0.23 Calc. By: Type of Grate:0.35 Diameter of Grate (ft):0.67 4,962.43 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,962.43 0.00 0.00 0.00 0.10 4,962.53 0.10 0.30 0.10 10-Year Storm 0.18 4,962.61 0.24 0.40 0.24 100-Year Storm 0.20 4,962.63 0.28 0.42 0.28 0.30 4,962.73 0.52 0.51 0.51 0.40 4,962.83 0.79 0.59 0.59 0.49 4,962.92 1.08 0.66 0.66 Overflow to Inlet 6-1 0.50 4,962.93 1.11 0.66 0.66 0.60 4,963.03 1.46 0.73 0.73 0.70 4,963.13 1.84 0.78 0.78 0.80 4,963.23 2.25 0.84 0.84 0.96 4,963.39 2.96 0.92 0.92 FG at Building Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 8" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 0.00 0.20 0.40 0.60 0.80 1.00 1.20Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet A7-1-1 Project: 10-Year Design Flow (cfs)0.02 Location: 100-Year Design Flow (cfs)0.05 Calc. By: Type of Grate:0.35 Diameter of Grate (ft):0.67 4,966.44 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,966.44 0.00 0.00 0.00 0.03 4,966.47 0.02 0.16 0.02 10-Year Storm 0.06 4,966.50 0.05 0.23 0.05 100-Year Storm 0.10 4,966.54 0.10 0.30 0.10 0.20 4,966.64 0.28 0.42 0.28 0.27 4,966.71 0.44 0.49 0.44 Low Point in Sidewalk 0.30 4,966.74 0.52 0.51 0.51 0.40 4,966.84 0.79 0.59 0.59 0.50 4,966.94 1.11 0.66 0.66 0.60 4,967.04 1.46 0.73 0.73 0.70 4,967.14 1.84 0.78 0.78 0.80 4,967.24 2.25 0.84 0.84 Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 8" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet A7-1-2 Project: 10-Year Design Flow (cfs)0.02 Location: 100-Year Design Flow (cfs)0.05 Calc. By: Type of Grate:0.35 Diameter of Grate (ft):0.67 4,966.43 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,966.43 0.00 0.00 0.00 0.03 4,966.46 0.02 0.16 0.02 10-Year Storm 0.06 4,966.49 0.05 0.23 0.05 100-Year Storm 0.10 4,966.53 0.10 0.30 0.10 0.20 4,966.63 0.28 0.42 0.28 0.30 4,966.73 0.52 0.51 0.51 0.40 4,966.83 0.79 0.59 0.59 0.50 4,966.93 1.11 0.66 0.66 0.54 4,966.97 1.25 0.69 0.69 Low Point in Sidewalk 0.60 4,967.03 1.46 0.73 0.73 0.70 4,967.13 1.84 0.78 0.78 0.80 4,967.23 2.25 0.84 0.84 Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 8" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet A7-2 Project: 10-Year Design Flow (cfs)0.15 Location: 100-Year Design Flow (cfs)0.42 Calc. By: Type of Grate:0.35 Diameter of Grate (ft):0.67 4,965.67 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,965.67 0.00 0.00 0.00 0.10 4,965.77 0.10 0.30 0.10 0.13 4,965.80 0.15 0.34 0.15 10-Year Storm 0.20 4,965.87 0.28 0.42 0.28 0.26 4,965.93 0.42 0.48 0.42 100-Year Storm 0.30 4,965.97 0.52 0.51 0.51 0.34 4,966.01 0.62 0.55 0.55 Overflow to Inlet A8 0.40 4,966.07 0.79 0.59 0.59 0.50 4,966.17 1.11 0.66 0.66 0.60 4,966.27 1.46 0.73 0.73 0.70 4,966.37 1.84 0.78 0.78 0.84 4,966.51 2.42 0.86 0.86 FG at Building Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 8" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 0.50 1.00 1.50 2.00 2.50 3.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet A7-3 Project: 10-Year Design Flow (cfs)0.15 Location: 100-Year Design Flow (cfs)0.42 Calc. By: Type of Grate:0.35 Diameter of Grate (ft):0.67 4,964.45 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,964.45 0.00 0.00 0.00 0.10 4,964.55 0.10 0.30 0.10 0.13 4,964.58 0.15 0.34 0.15 10-Year Storm 0.20 4,964.65 0.28 0.42 0.28 0.26 4,964.71 0.42 0.48 0.42 100-Year Storm 0.50 4,964.95 1.11 0.66 0.66 0.75 4,965.20 2.04 0.81 0.81 1.00 4,965.45 3.14 0.94 0.94 1.25 4,965.70 4.39 1.05 1.05 1.56 4,966.01 6.12 1.17 1.17 Overflow to Inlet A11 1.80 4,966.25 7.59 1.26 1.26 2.06 4,966.51 9.29 1.35 1.35 FG at Building Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 8" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 0.00 0.50 1.00 1.50 2.00 2.50Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet A8 Project: 10-Year Design Flow (cfs)0.30 Location: 100-Year Design Flow (cfs)0.83 Calc. By: Type of Grate:0.79 Diameter of Grate (ft):1.00 4,964.71 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,964.71 0.00 0.00 0.00 0.10 4,964.81 0.15 0.67 0.15 0.16 4,964.87 0.30 0.84 0.30 10-Year Storm 0.20 4,964.91 0.42 0.94 0.42 0.30 4,965.01 0.77 1.16 0.77 0.32 4,965.03 0.85 1.19 0.85 100-Year Storm 0.40 4,965.11 1.19 1.33 1.19 0.50 4,965.21 1.67 1.49 1.49 0.76 4,965.47 3.12 1.84 1.84 Overflow to Inlet A11 1.00 4,965.71 4.71 2.11 2.11 1.25 4,965.96 6.59 2.36 2.36 1.80 4,966.51 11.38 2.83 2.83 FG at Building Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 12" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 2.00 4.00 6.00 8.00 10.00 12.00 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60 1.80 2.00Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet A11 Project: 10-Year Design Flow (cfs)0.30 Location: 100-Year Design Flow (cfs)0.83 Calc. By: Type of Grate:0.79 Diameter of Grate (ft):1.00 4,964.33 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,964.33 0.00 0.00 0.00 0.10 4,964.43 0.15 0.67 0.15 0.16 4,964.49 0.30 0.84 0.30 10-Year Storm 0.20 4,964.53 0.42 0.94 0.42 0.30 4,964.63 0.77 1.16 0.77 0.32 4,964.65 0.85 1.19 0.85 100-Year Storm 0.40 4,964.73 1.19 1.33 1.19 0.52 4,964.85 1.77 1.52 1.52 Overflow to the west 0.80 4,965.13 3.37 1.89 1.89 1.25 4,965.58 6.59 2.36 2.36 1.75 4,966.08 10.91 2.79 2.79 2.18 4,966.51 15.17 3.12 3.12 FG at Building Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 12" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 2.00 4.00 6.00 8.00 10.00 12.00 14.00 16.00 0.00 0.50 1.00 1.50 2.00 2.50Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet B4 Project: 10-Year Design Flow (cfs)0.20 Location: 100-Year Design Flow (cfs)0.50 Calc. By: Type of Grate:0.79 Diameter of Grate (ft):1.00 4,961.24 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,961.24 0.00 0.00 0.00 0.10 4,961.34 0.15 0.67 0.15 0.12 4,961.36 0.20 0.73 0.20 10-Year Storm 0.20 4,961.44 0.42 0.94 0.42 0.23 4,961.47 0.52 1.01 0.52 100-Year Storm 0.30 4,961.54 0.77 1.16 0.77 0.40 4,961.64 1.19 1.33 1.19 0.50 4,961.74 1.67 1.49 1.49 0.63 4,961.87 2.36 1.68 1.68 Overflow to the east 0.75 4,961.99 3.06 1.83 1.83 1.00 4,962.24 4.71 2.11 2.11 1.25 4,962.49 6.59 2.36 2.36 FG at Building Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 12" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet B5 Project: 10-Year Design Flow (cfs)0.10 Location: 100-Year Design Flow (cfs)0.25 Calc. By: Type of Grate:0.35 Diameter of Grate (ft):0.67 4,961.55 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,961.55 0.00 0.00 0.00 0.10 4,961.65 0.10 0.30 0.10 10-Year Storm 0.19 4,961.74 0.26 0.41 0.26 100-Year Storm 0.30 4,961.85 0.52 0.52 0.52 0.40 4,961.95 0.80 0.60 0.60 0.44 4,961.99 0.92 0.63 0.63 Overflow to Inlet B6 0.50 4,962.05 1.12 0.67 0.67 0.60 4,962.15 1.47 0.73 0.73 0.70 4,962.25 1.85 0.79 0.79 0.80 4,962.35 2.26 0.85 0.85 0.90 4,962.45 2.70 0.90 0.90 0.94 4,962.49 2.88 0.92 0.92 FG at Building Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 8" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet B6 Project: 10-Year Design Flow (cfs)0.10 Location: 100-Year Design Flow (cfs)0.25 Calc. By: Type of Grate:0.35 Diameter of Grate (ft):0.67 4,961.54 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,961.54 0.00 0.00 0.00 0.10 4,961.64 0.10 0.30 0.10 10-Year Storm 0.19 4,961.73 0.26 0.41 0.26 100-Year Storm 0.30 4,961.84 0.52 0.52 0.52 0.40 4,961.94 0.80 0.60 0.60 0.45 4,961.99 0.95 0.64 0.64 Overflow to Inlet B6 0.51 4,962.05 1.15 0.68 0.68 0.61 4,962.15 1.50 0.74 0.74 0.71 4,962.25 1.89 0.80 0.80 0.81 4,962.35 2.30 0.85 0.85 0.91 4,962.45 2.74 0.90 0.90 0.95 4,962.49 2.92 0.92 0.92 FG at Building Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 8" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet B6-1 Project: 10-Year Design Flow (cfs)0.02 Location: 100-Year Design Flow (cfs)0.05 Calc. By: Type of Grate:0.35 Diameter of Grate (ft):0.67 4,962.99 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,962.99 0.00 0.00 0.00 0.03 4,963.02 0.02 0.16 0.02 10-Year Storm 0.06 4,963.05 0.05 0.23 0.05 100-Year Storm 0.10 4,963.09 0.10 0.30 0.10 Overflow to Inlet B6 0.20 4,963.19 0.28 0.42 0.28 0.30 4,963.29 0.52 0.52 0.52 0.40 4,963.39 0.80 0.60 0.60 0.50 4,963.49 1.12 0.67 0.67 0.60 4,963.59 1.47 0.73 0.73 0.70 4,963.69 1.85 0.79 0.79 0.80 4,963.79 2.26 0.85 0.85 0.89 4,963.88 2.65 0.89 0.89 FG at Building Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 8" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 0.50 1.00 1.50 2.00 2.50 3.00 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet B7 Project: 10-Year Design Flow (cfs)0.20 Location: 100-Year Design Flow (cfs)0.50 Calc. By: Type of Grate:0.35 Diameter of Grate (ft):0.67 4,961.54 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,961.54 0.00 0.00 0.00 0.10 4,961.64 0.10 0.30 0.10 0.16 4,961.70 0.20 0.38 0.20 10-Year Storm 0.20 4,961.74 0.28 0.42 0.28 0.30 4,961.84 0.52 0.52 0.52 100-Year Storm 0.40 4,961.94 0.80 0.60 0.60 0.45 4,961.99 0.95 0.64 0.64 Overflow to Inlet B6 0.50 4,962.04 1.12 0.67 0.67 0.60 4,962.14 1.47 0.73 0.73 0.70 4,962.24 1.85 0.79 0.79 0.80 4,962.34 2.26 0.85 0.85 0.95 4,962.49 2.92 0.92 0.92 FG at Building Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 8" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet C1 Project: 10-Year Design Flow (cfs)0.10 Location: 100-Year Design Flow (cfs)0.20 Calc. By: Type of Grate:0.35 Diameter of Grate (ft):0.67 4,955.29 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,955.29 0.00 0.00 0.00 0.10 4,955.39 0.10 0.30 0.10 0.20 4,955.49 0.28 0.42 0.28 10-Year Storm 0.30 4,955.59 0.52 0.51 0.51 0.40 4,955.69 0.79 0.59 0.59 0.50 4,955.79 1.11 0.66 0.66 0.60 4,955.89 1.46 0.73 0.73 100-Year Storm 0.70 4,955.99 1.84 0.78 0.78 0.80 4,956.09 2.25 0.84 0.84 0.90 4,956.19 2.68 0.89 0.89 1.00 4,956.29 3.14 0.94 0.94 Overflow to the east Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 8" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50 0.00 0.20 0.40 0.60 0.80 1.00 1.20Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet C2 Project: 10-Year Design Flow (cfs)0.10 Location: 100-Year Design Flow (cfs)0.20 Calc. By: Type of Grate:0.35 Diameter of Grate (ft):0.67 4,957.75 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,957.75 0.00 0.00 0.00 0.10 4,957.85 0.10 0.30 0.10 0.20 4,957.95 0.28 0.42 0.28 10-Year Storm 0.30 4,958.05 0.52 0.51 0.51 0.40 4,958.15 0.79 0.59 0.59 0.50 4,958.25 1.11 0.66 0.66 0.60 4,958.35 1.46 0.73 0.73 100-Year Storm 0.75 4,958.50 2.04 0.81 0.81 0.90 4,958.65 2.68 0.89 0.89 1.05 4,958.80 3.38 0.96 0.96 1.20 4,958.95 4.13 1.03 1.03 1.43 4,959.18 5.37 1.12 1.12 Overflow to the east Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 8" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 1.00 2.00 3.00 4.00 5.00 6.00 0.00 0.20 0.40 0.60 0.80 1.00 1.20 1.40 1.60Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Inlet Name:Inlet C3 Project: 10-Year Design Flow (cfs)0.10 Location: 100-Year Design Flow (cfs)0.20 Calc. By: Type of Grate:0.35 Diameter of Grate (ft):0.67 4,958.09 0.50 Depth Above Inlet (ft)Elevation (ft) Shallow Weir Flow (cfs) Orifice Flow (cfs) Actual Flow (cfs)Notes 0.00 4,958.09 0.00 0.00 0.00 0.10 4,958.19 0.10 0.30 0.10 0.20 4,958.29 0.28 0.42 0.28 10-Year Storm 0.30 4,958.39 0.52 0.51 0.51 0.40 4,958.49 0.79 0.59 0.59 0.50 4,958.59 1.11 0.66 0.66 0.60 4,958.69 1.46 0.73 0.73 100-Year Storm 0.75 4,958.84 2.04 0.81 0.81 1.00 4,959.09 3.14 0.94 0.94 1.25 4,959.34 4.39 1.05 1.05 1.50 4,959.59 5.77 1.15 1.15 2.01 4,960.10 8.95 1.33 1.33 Overflow to the east Depth vs. Flow AREA INLET PERFORMANCE CURVE 1328-010 Forty-Three Prime F. Wegert Governing Equations If H > 1.792 (A/P), then the grate operates like an orifice; otherwise it operates like a weir. Input Parameters Nyloplast 8" Dome Open Area of Grate (ft2): Rim Elevation (ft): Reduction Factor: 0.00 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 9.00 10.00 0.00 0.50 1.00 1.50 2.00 2.50Discharge (cfs)Stage (ft) Stage -Discharge Curves Series1 Series2 At low flow dephs, the inlet will act like a weir governed by the following equation: * where P = π * Dia. of grate * where H corresponds to the depth of water above the flowline At higher flow depths, the inlet will act like an orifice governed by the following equation: * where A equals the open area of teh inlet grate * where H corresponds to the depth of water above the centroid of the cross - sectional area (A). 𝑃=3.0𝑃𝐻1.5 𝑃=0.67𝐴(2𝑔𝐻)0.5 NORTHERNENGINEERING.COM | 970.221.4158 FORT COLLINS | GREELEY Storm Sewer A - 100-Year Storm Sewer A - 100-Year Storm Sewer A - 100-Year Storm Sewer A2 - 100-Year Storm Sewer A7 - 100-Year Storm Sewer A7-1 - 100-Year Storm Sewer B - 100-Year Storm Sewer B - 100-Year Storm Sewer B6 - 100-Year Storm Sewer C1 - 100-Year Storm Sewer C1 - 100-Year Storm Sewer C1 - 100-Year Storm Sewer C2 - 100-Year Storm Sewer C2 - 100-Year Storm Sewer C2 - 100-Year Storm Sewer C3 - 100-Year Storm Sewer C3 - 100-Year Storm Sewer C3 - 100-Year AUTUMN R IDGE DR 64.33 64.716 6 . 0 1 65.736 4 . 8 5 66.01FFE=67.18 BLDG F 66.01 65. 6 7 64.51PROPOSED INLET PROPOSED INLET PROPOSED INLET PROPOSED INLET 66.17 UD UD UD MAIL FFE=64.06 BLDG E62.4862.4362.4862.9163.1663.776 2 . 7 8 64.87PROPOSED INLET PROPOSED INLET D UD UD UD T FFE=63.15 BLDG D 61. 6 6 61. 5 561.9961.5463.2661.9961.546 2 . 3 362.756 4 . 1 3 PROPOSED INLET PROPOSED INLET PROPOSED INLET 6 1 . 5 7 DRAINAGE OVERFLOW PATHS FORT COLLINS, CO FORTY-THREE PRIME E N G I N E E R N GI EHTRON R N NOVEMBER 14, 2018 D:\PROJECTS\1328-010\DWG\EXHIBITS\FORTY THREE PRIME-OVERFLOW PATH.DWG BUILDING F BUILDING E BUILDING D ( IN FEET ) 0 1 INCH = 30 FEET 30 30 Circular D or Da, Pipe Diameter (ft) H or Ha, Culvert Height (ft) W, Culvert Width (ft) Yt/D Q/D1.5 Q/D2.5 Yt/H Q/WH0.5 Storm A 3.81 1.25 0.50 0.40 2.73 2.18 N/A N/A 6.00 2.18 0.64 0.12 Type L 4.00 5.00 1.5 Storm B 1.60 1.00 0.20 0.20 1.60 1.60 N/A N/A 3.00 1.60 0.27 1.00 Type L 4.00 4.00 1.5 Pipe End 1 6.45 1.00 0.40 0.40 6.45 6.45 N/A N/A 2.00 6.45 2.15 8.75 Type L 9.00 4.00 1.5 Pipe End 2 6.45 1.00 0.40 0.40 6.45 6.45 N/A N/A 2.00 6.45 1.61 6.06 Type L 7.00 4.00 1.5 CALCULATIONS FOR RIPRAP PROTECTION AT PIPE OUTLETS Circular Pipe (Figure MD-21) Rectangular Pipe (Figure MD-22)Spec Width of Riprap (ft) 2*d50, Depth of Riprap (ft) for L/2 Froude Parameter Q/D2.5 Max 6.0 or Q/WH1.5 Max 8.0 Riprap Type (From Figure MD-21 or MD-22) Project: 1328-010 Urban Drainage pg MD-107 L= 1/(2tanq)* [At/Yt)-W] (ft) INPUT Storm Line/Culvert Label Design Discharge (cfs) Expansion Factor 1/(2tanq) (From Figure MD-23 or MD-24) OUTPUT Spec Length of Riprap (ft) Box Culvert Yt, Tailwater Depth (ft) Culvert Parameters At=Q/V (ft) By: F. Wegert CALCULATE Date: 07/28/2021 See following sheets from Urban Drainage Volume 1 (2011) for how riprap was sized. The current Mile High Flood Control criteria does not adequately describe how to size riprap. DRAINAGE CRITERIA MANUAL (V. 1) MAJOR DRAINAGE 7.0 PROTECTION DOWNSTREAM OF PIPE OUTLETS This section is intended to address the use of riprap for erosion protection downstream of conduit and culvert outlets that are in-line with major drainageway channels. Inadequate protection at conduit and culvert outlets has long been a major problem. The designer should refer to Section 4.4 for additional information on major drainage applications utilizing riprap. In addition, the criteria and guidance in Section 4.4 may be useful in design of erosion protection for conduit outlets. The reader is referred to Section 7.0 of the HYDRAULIC STRUCTURES chapter of this Manual for information on rundowns, and to Section 3.0 of the HYDRAULIC STRUCTURES chapter for additional discussion on culvert outfall protection. Scour resulting from highly turbulent, rapidly decelerating flow is a common problem at conduit outlets. The riprap protection design protocol is suggested for conduit and culvert outlet Froude numbers up to 2.5 (i.e., Froude parameters Q/d02.5 or Q/WH1.5 up to 14 ft0.5/sec) where the channel and conduit slopes are parallel with the channel gradient and the conduit outlet invert is flush with the riprap channel protection. Here, Q is the discharge in cfs, d0 is the diameter of a circular conduit in feet and W and H are the width and height, respectively, of a rectangular conduit in feet. 7.1 Configuration of Riprap Protection Figure MD-25 illustrates typical riprap protection of culverts and major drainageway conduit outlets. The additional thickness of the riprap just downstream from the outlet is to assure protection from flow conditions that might precipitate rock movement in this region. 7.2 Required Rock Size The required rock size may be selected from Figure MD-21 for circular conduits and from Figure MD-22 for rectangular conduits. Figure MD-21 is valid for Q/Dc2.5 of 6 or less and Figure MD-22 is valid for Q/WH1.5 of 8.0 or less. The parameters in these two figures are: 1. Q/D1.5 or Q/WH0.5 in which Q is the design discharge in cfs, Dc is the diameter of a circular conduit in feet, and W and H are the width and height of a rectangular conduit in feet. 2. Yt/Dc or Yt/H in which Yt is the tailwater depth in feet, Dc is the diameter of a circular conduit in feet, and H is the height of a rectangular conduit in feet. In cases where Yt is unknown or a hydraulic jump is suspected downstream of the outlet, use Yt/Dt = Yt/H = 0.40 when using Figures MD-21 and MD-22. Rev. 04/2008 MD-103 Urban Drainage and Flood Control District This is from UDFCD Vol 1. From 2011 DRAINAGE CRITERIA MANUAL (V. 1) MAJOR DRAINAGE Figure MD-21—Riprap Erosion Protection at Circular Conduit Outlet Valid for Q/D2.5 ≤ 6.0 Rev. 04/2008 MD-107 Urban Drainage and Flood Control District DRAINAGE CRITERIA MANUAL (V. 1) MAJOR DRAINAGE Figure MD-23—Expansion Factor for Circular Conduits Rev. 04/2008 MD-109 Urban Drainage and Flood Control District DRAINAGE CRITERIA MANUAL (V. 1) MAJOR DRAINAGE Table MD-7—Classification and Gradation of Ordinary Riprap Riprap Designation % Smaller Than Given Size by Weight Intermediate Rock Dimensions (inches) d50 (inches)* Type VL 70-100 50-70 35-50 2-10 12 9 6 2 6** Type L 70-100 50-70 35-50 2-10 15 12 9 3 9** Type M 70-100 50-70 35-50 2-10 21 18 12 4 12** Type H 70-100 50-70 35-50 2-10 30 24 18 6 18 Type VH 70-100 50-70 35-50 2-10 42 33 24 9 24 * d50 = mean particle size (intermediate dimension) by weight. ** Mix VL, L and M riprap with 35% topsoil (by volume) and bury it with 4 to 6 inches of topsoil, all vibration compacted, and revegetate. Basic requirements for riprap stone are as follows: • Rock shall be hard, durable, angular in shape, and free from cracks, overburden, shale, and organic matter. • Neither breadth nor thickness of a single stone should be less than one-third its length, and rounded stone should be avoided. • The rock should sustain a loss of not more than 40% after 500 revolutions in an abrasion test (Los Angeles machine⎯ASTM C-535-69) and should sustain a loss of not more than 10% after 12 cycles of freezing and thawing (AASHTO test 103 for ledge rock procedure A). • Rock having a minimum specific gravity of 2.65 is preferred; however, in no case should rock have a specific gravity less than 2.50. 4.4.1.2 Grouted Boulders Table MD-8 provides the classification and size requirements for boulders. When grouted boulders are used, they provide a relatively impervious channel lining which is less subject to vandalism than ordinary riprap. Grouted boulders require less routine maintenance by reducing silt and trash accumulation and Rev. 04/2008 MD-61 Urban Drainage and Flood Control District North American Green 5401 St. Wendel-Cynthiana Rd. Poseyville, Indiana 47633 Tel. 800.772.2040 >Fax 812.867.0247 www.nagreen.com ECMDS v7.0 SLOPE ANALYSIS > > > Rain Garden Spillway Country United States State/Region Colorado City Ft. Collins Annual R Factor 30.00 Adjusted R Factor 0.00 Total Slope Length 46 Protection Type Permanent Protection Period 0 Beginning Month Slope Gradient (H:1) 7 Soil Type Clay Loam K Factor 0.21 Reach 1Start: 0ft End: 46 ftVegetation Type: >95% P300 0.1 in 0.0 in 0.1 in 0.0 in 0.25 in >10 STABLE D P550 0.1 in 0.0 in 0.1 in 0.0 in 0.25 in 0 UNSTABLE D C350 0.1 in 0.0 in 0.1 in 0.0 in 0.25 in >10 STABLE D SC250 0.1 in 0.0 in 0.1 in 0.0 in 0.25 in >10 STABLE D W3000 0.1 in 0.0 in 0.1 in 0.0 in 0.25 in >10 STABLE B TMax 0.1 in 0.0 in 0.1 in 0.0 in 0.25 in >10 STABLE B Estb. Veg. 0.1 in 0.0 in N/A in N/A in 0.03 in >10 STABLE -- P300 Reinf. Veg 0.1 in 0.0 in 0.1 in 0.0 in 0.03 in >10 STABLE D SC250 Reinf. Veg 0.1 in 0.0 in 0.1 in 0.0 in 0.03 in >10 STABLE D C350 Reinf. Veg 0.1 in 0.0 in 0.1 in 0.0 in 0.03 in >10 STABLE D P550 Reinf. Veg 0.1 in 0.0 in 0.1 in 0.0 in 0.03 in 0 UNSTABLE D Material ASL bare ASL mat MSL bare MSL mat Soil Loss Tolerance SF Remarks Staple / App Rate ECMDS 7.0 https://ecmds.com/project/148940/slope-analysis/207531/show 1 of 1 7/26/2021, 11:06 AM DESCRIPTION The permanent erosion control blanket shall be a machine-produced mat of 100% UV stable polypropylene fiber. The matting shall be of consistent thickness with the synthetic fibers evenly distributed over the entire area of the mat. The matting shall be covered on the top side with black heavyweight UV-stabilized polypropylene netting having ultraviolet additives to delay breakdown and an approximate 0.50 x 0.50 inch (1.27 x 1.27 cm) mesh. The bottom net shall also be UV- stabilized polypropylene with a 0.63 x 0.63 inch (1.57 x 1.57 cm) mesh size. The blanket shall be sewn together on 1.5 inch (3.81 cm) centers with non-degradable thread. All mats shall be manufactured with a colored thread stitched along both outer edges as an overlap guide for adjacent mats. The P300 shall meet Type 5A, 5B, specification requirements established by the Erosion Control Technology Council (ECTC) and Federal Highway Administration’s (FHWA) FP-03 Section 713.18 Material Content Matrix 100% UV stable Polypropylene Fiber 0.7 lbs/sq yd (0.38 kg/sm) Netting Top: UV-stabilized Polypropylene Bottom: UV-stabilized Polypropylene 5 lbs/1000 sq ft (24.4 g/sm) 3 lbs/1000 sq ft (14.7 g/sm) Thread Polypropylene, UV stable Standard Roll Sizes Width 6.67 ft (2.03 m)8 ft (2.44 m) Length 108 ft (32.92 m) 112 ft (35.14 m) Weight ± 10%61 lbs (27.66 kg) 76.25 lbs (34.59 kg) Area 80 sq yd (66.0 sm) 100 sq yd (83.61 sm) Slope Design Data: C Factors Slope Gradients (S) Slope Length (L)≤ 3:1 3:1 – 2.1 ≥ 2:1 ≤ 20 ft (6 m)0.001 0.029 0.082 20-50 ft 0.036 0.060 0.086 ≥ 50 ft (15.2 m)0.070 0.090 0.110 Index Property Test Method Typical Thickness ASTM D6525 0.47 in. (11.94 mm) Resiliency ASTM D6524 91.5% Density ASTM D792 0.916 g/cm3 Mass/Unit Area ASTM 6566 13.03 oz/sy (443 g/m2) UV Stability ASTM D4355/ 1000 hr 90% Porosity ECTC Guidelines 95.89% Stiffness ASTM D1388 0.94 in-lb (1085378 mg-cm) Light Penetration ASTM D6567 17.9% Tensile Strength - MD ASTM D6818 438 lbs/ft (6.49 kN/m) Elongation - MD ASTM D6818 28.1% Tensile Strength - TD ASTM D6818 291.9 lbs/ft (4.32 kN/m) Elongation - TD ASTM D6818 26.7% Biomass Improvement ASTM D7322 497% Design Permissible Shear Stress Short Duration Long Duration Phase 1: Unvegetated 3.0 psf (144 Pa)2.0 psf (96 Pa) Phase 2: Partially Veg.8.0 psf (383 Pa)8.0 psf (383 Pa) Phase 3: Fully Veg.8.0 psf (383 Pa)8.0 PSF (383 Pa) Unvegetated Velocity 9.0 fps (2.7 m/s) Vegetaged Velocity 16 fps (4.9 m/s) Roughness Coefficients – Unveg. Flow Depth Manning’s n ≤ 0.50 ft (0.15 m)0.034 0.50 – 2.0 ft 0.034-0.020 ≥ 2.0 ft (0.60 m)0.020 Specification Sheet EroNet™ P300® Permanent Erosion Control Blanket EC_RMX_MPDS_P300_1.19 ©2019, North American Green is a registered trademark from Western Green. Certain products and/or applications described or illustrated herein are protected under one or more U.S. patents. Other U.S. patents are pending, and certain foreign patents and patent applications may also exist.Trademark rights also apply as indicated herein. Final determination of the suitability of any information or material for the use contemplated, and its manner of use, is the sole responsibility of the user. Printed in the U.S.A. Western Green 4609 E. Boonville-New Harmony Rd. Evansville, IN 47725 nagreen.com 800-772-2040 ATTACHMENT 3 LID/WATER QUALITY CALCULATIONS 4YD4YD4YD4YDCCTFESFESFESFESLIDLIDLID/ / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / /DDDDDDDDRAIN GARDENREQUIRED VOLUME: 1,873 CU. FT.PROVIDED VOLUME: 1,904 CU. FT.TREATMENT AREA: 76,305 SFFORTY-THREE PRIMESHEET NO:D:\PROJECTS\1328-010\DWG\DRNG\1328-010_LID.DWG301 N. Howes Street, Suite 100Fort Collins, Colorado 80521ENGINEERNGIEHTRONRNPHONE: 970.221.4158www.northernengineering.comDRAWING REFERENCE:LID TREATMENT EXHIBITF. Wegert1 in = 60 ftJuly 28, 2021LID-1DRAWN BY:SCALE:ISSUED:( IN FEET )01 INCH = 60 FEET6060LEGENDUNTREATED AREARAIN GARDEN AREARAIN GARDENTREATMENT AREAFORTY-THREE PRIME ON-SITE LID TREATMENTProject SummaryTotal Impervious Area 89,082sfTarget Treatment Percentage75%Minimum Area to be Treated by LID measures 66,812sfRain GardenTotal Rain Garden Treatment Area76,305sfTotal Treatment Area76,305sfPercent Total Project Area Treated85.7% Sheet 1 of 2 Designer: Company: Date: Project: Location: 1. Basin Storage Volume A) Effective Imperviousness of Tributary Area, Ia Ia =68.0 % (100% if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio (i = Ia/100)i = 0.680 C) Water Quality Capture Volume (WQCV) for a 12-hour Drain Time WQCV = 0.21 watershed inches (WQCV= 0.8 * (0.91* i3 - 1.19 * i2 + 0.78 * i) D) Contributing Watershed Area (including rain garden area) Area = 105,502 sq ft E) Water Quality Capture Volume (WQCV) Design Volume VWQCV =1,873 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 =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 =12 in B) Rain Garden Side Slopes (Z = 4 min., horiz. dist per unit vertical) Z = 0.00 ft / ft (Use "0" if rain garden has vertical walls) C) Mimimum Flat Surface Area AMin =1435 sq ft D) Actual Flat Surface Area AActual =1904 sq ft E) Area at Design Depth (Top Surface Area)ATop =1904 sq ft F) Rain Garden Total Volume VT=1,904 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 =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) F. Wegert Northern Engineering July 28, 2021 Forty-Three Prime Fort Collins, CO UD-BMP (Version 3.06, November 2016) Choose One Choose One 18" Rain Garden Growing Media Other (Explain): YES NO UD-BMP_v3.06_Double Rain Garden WQVol-FSW.xlsm, RG 7/26/2021, 1:12 PM 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? PROVIDE A 30 MIL (MIN) PVC LINER WITH CDOT CLASS B GEOTEXTILE ABOVE IT. USE THE SAME GEOTEXTILE BELOW THE LINER IF THE SUBGRADE IS ANGULAR 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) F. Wegert Northern Engineering July 28, 2021 Forty-Three Prime Fort Collins, CO Choose One Choose One Choose One Sheet Flow- No Energy Dissipation Required Concentrated Flow- Energy Dissipation Provided Plantings Seed (Plan for frequent weed control) Sand Grown or Other High Infiltration Sod Choose One YES NO YES NO UD-BMP_v3.06_Double Rain Garden WQVol-FSW.xlsm, RG 7/26/2021, 1:12 PM PAVER PARKING AREA Project: 43 Prime By: A. Reese REQUIRED STORAGE & OUTLET WORKS: BASIN AREA (acres)=1.620 <-- INPUT from impervious calcs BASIN IMPERVIOUSNESS PERCENT =80.00 <-- INPUT from impervious calcs BASIN IMPERVIOUSNESS RATIO =0.8000 <-- CALCULATED Drain Time (hrs)12 <-- INPUT Drain Time Coefficient 0.8 <-- CALCULATED from Figure Table 3-2 WQCV (watershed inches) =0.263 <-- CALCULATED from Figure EDB-2 WQCV (ac-ft) =0.035 <-- CALCULATED from UDFCD DCM V.3 Section 6.5 Adjusted WQCV (ac-ft) =0.0426 <-- CALCULATED (20% Sedimentation Accumulation) Adjusted WQCV (cu-ft) =1853 <-- CALCULATED (20% Sedimentation Accumulation) WATER QUALITY CONTROL STRUCTURE PLATE July 28, 2021 ATTACHMENT 4 PREVIOUS REPORT EXCERPTS This unofficial copy was downloaded on Aug-14-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.com For additional information or an official copy, please contact Engineering Office 281 North College Fort Collins, CO 80521 USA This unofficial copy was downloaded on Aug-14-2018 from the City of Fort Collins Public Records Website: http://citydocs.fcgov.comFor additional information or an official copy, please contact Engineering Office 281 North College Fort Collins, CO 80521 USA ATTACHMENT 5 DRAINAGE EXHIBITS USGS The National Map: Orthoimagery. Data refreshed October 2017. National Flood Hazard Layer FIRMette 0 500 1,000 1,500 2,000250Feet Ü105°4'5.57"W 40°29'50.10"N 105°3'28.11"W 40°29'22.74"N SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT SPECIAL FLOODHAZARD AR EAS Without Base Flood Elevation (BFE)Zone A, V, A99With BFE or Depth Zone AE, AO, AH, VE, AR Regulator y Floodway 0.2% Annual Chance Flood Hazard, Areasof 1% annual chance flood with averagedepth less than one foot or with drainageareas of less than one square mile Zone X Future Conditions 1% AnnualChance Flood Hazard Zone XArea with Reduced Flood Risk due toLevee. See Notes.Zone X Area with Flood Risk due to Levee Zone D NO SCREE N Area of Minimal Flood Hazard Zone X Area of Undetermined Flood Hazard Zone D Channel, Culver t, or Storm SewerLevee, Dike, or Floodwall Cross Sections with 1% Annual Chance17.5 Water Surface ElevationCoastal Transect Coastal Transect BaselineProfile BaselineHydrographic Feature Base Flood Elevation Line (BFE) Effective LOMRs Limit of StudyJurisdiction Boundar y Digital Data Available No Digital Data Available Unmapped This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below. The basemap shown complies with FEMA's basemap accuracy standards The flood hazard information is derived directly from theauthoritative NFHL web services provided by FEMA. This mapwas exported on 9/26/2018 at 10:31:24 AM and does notreflect changes or amendments subsequent to this date andtime. The NFHL and effective information may change orbecome superseded by new data over time. This map image is void if the one or more of the following mapelements do not appear: basemap imagery, flood zone labels,legend, scale bar, map creation date, community identifiers,FIRM panel number, and FIRM effective date. Map images forunmapped and unmodernized areas cannot be used forregulatory purposes. Legend OTHER AREAS OFFLOOD HAZARD OTHER AREAS GENERALSTRUCTURES OTHERFEATURES MAP PANELS 8 1:6,000 B 20.2 The pin displayed on the map is an approximate point selected by the user and does not represent an authoritative proper ty location. ST STSTSTC C T FE SF E SCONTROL IRR CONTROL IRR CONTROL IRR CONTROL IRR CONTROL IRR CONTROL IRRFES FE SLID LID LID / / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / /D D D D D D D D 4YD4YD4YD4YDUD UD UD C OS1 C A OS1 B1 B3 B4 OS1 0.23 AC A 1.64 AC B1 0.15 AC B3 0.15 AC B4 0.45 AC C 2.21 AC EXISTING STORM DRAIN EXISTING STORM DRAIN EXISTING STORM DRAIN EXISTING STORM DRAIN PROPOSED AREA DRAIN PROPOSED AREA DRAIN PROPOSED AREA DRAIN EXISTING INLET EXISTING INLET EXISTING INLET EXISTING INLET EXISTING INLET PROPOSED RAIN GARDENPROPOSED 2' CONCRETE CHASE PROPOSED RAIN GARDEN PROPOSED UNDERDRAIN PROPOSED 1'SIDEWALK CHASE PROPOSED 1' SIDEWALK CHASE PROPOSED 1' SIDEWALK CHASE PROPOSED 7.5' SIDEWALK CULVERT PROPOSED CULVERTS EAST TRILBY ROAD CAND L E W O O D D RI V E BRITTANY DRIVEAUTUMN RIDGE DRIVELOT 2 TRACT A LOT 1 BLDG A BLDG B BLDG C BLDG D BLDG E BLDG F PROPOSED CULVERT STORM INLET B4 STORM INLET B5 STORM INLET B6 STORM INLET B7 STORM INLET B6-1 B2 0.03 AC B2 STORM INLET A2-1 STORM INLET A4 STORM INLET A6-1 STORM INLET A6-2 STORM INLET A7-2 STORM INLET A7-3 STORM INLET A7-1-2 STORM INLET A7-1-1 STORM INLET A8 STORM INLET A11 TURF REINFORCEMENT MAT HYDROLOGY SUMMARYLID SUMMARY SheetFORTY-THREE PRIMEThese drawings areinstruments of serviceprovided by NorthernEngineering Services, Inc.and are not to be used forany type of constructionunless signed and sealed bya Professional Engineer inthe employ of NorthernEngineering Services, Inc.NOT FOR CONSTRUCTIONREVIEW SETENGINEERNGIEHTRONRNFORT COLLINS: 301 North Howes Street, Suite 100, 80521GREELEY: 820 8th Street, 80631970.221.4158northernengineering.comof 18 DR2 DEVELOPED DRAINAGE EXHIBITX Basin ID Basin Area (s.f.) Basin Area (ac) Composite % Imperv. Flow, WQ (cfs) Flow, Q2 (cfs) Flow, Q100 (cfs) Treatment Area (sf) OS1 10130 0.23 40%0.18 0.36 1.59 4315.00 A 71360 1.64 79%1.50 3.01 12.90 59264.00 B1 6712 0.15 68%0.17 0.34 1.50 5103.00 B2 1190 0.03 59%0.03 0.06 0.24 784.00 B3 6716 0.15 39%0.10 0.21 0.92 2921.16 B4 19524 0.45 39%0.28 0.55 2.46 8565.00 C 96480 2.21 8%0.48 0.97 4.36 9091.00 PROPOSED COMPOSITE % IMPERVIOUSNESS FORTY-THREE PRIME ON-SITE LID TREATMENT Project Summary Total Impervious Area 89,082 sf Target Treatment Percentage 75% Minimum Area to be Treated by LID measures 66,812 sf Rain Garden Total Rain Garden Treatment Area 76,305 sf Total Treatment Area 76,305 sf Percent Total Project Area Treated 85.7% Basin ID Basin Area (ac)Composite % Imperv. 100-year Composite Runoff Coefficient OS1 0.23 40%0.69 A 1.64 79%1.00 B1 0.15 68%0.98 B2 0.03 59%0.89 B3 0.15 39%0.69 B4 0.45 39%0.70 C 2.21 8%0.39 Total Site 4.87 39.7%0.44 A 1.62 AC LEGEND: PROPOSED CONTOUR PROPOSED STORM SEWER PROPOSED SWALE EXISTING CONTOUR PROPOSED CURB & GUTTER PROPERTY BOUNDARY PROPOSED INLET ADESIGN POINT FLOW ARROW DRAINAGE BASIN LABEL DRAINAGE BASIN BOUNDARY PROPOSED SWALE SECTION 11 NOTES: 1.REFER TO THE FINAL DRAINAGE LETTER AND LID REPORT FOR FORTY-THREE PRIME BY NORTHERN ENGINEERING DATED 7/28/2021, AND THE FINAL DRAINAGE AND EROSION CONTROL REPORT FOR PROVINCETOWNE PUD FILING TWO, DATED MARCH 22, 2001 BY MANHARD CONSULTING, LTD., FOR ADDITIONAL INFORMATION. 2.THE NATURAL HABITAT BUFFER ZONE IS INTENDED TO BE MAINTAINED IN A NATIVE LANDSCAPE. PLEASE SEE SECTION 3.4.1 OF LAND USE CODE FOR ALLOWABLE USES WITHIN THE NATURAL HABITAT BUFFER ZONE. UDPROPOSED UNDERDRAIN EXISTING NATURAL HABITAT BUFFER ZONE PROPOSED NATURAL HABITAT BUFFER ZONE EXISTING WETLAND FOR DRAINAGE REVIEW ONLY NOT FOR CONSTRUCTION CALL 2 BUSINESS DAYS IN ADVANCE BEFORE YOU DIG, GRADE, OR EXCAVATE FOR THE MARKING OF UNDERGROUND MEMBER UTILITIES. CALL UTILITY NOTIFICATION CENTER OF COLORADO Know what'sbelow. before you dig.Call R NORTH EMERGENCY OVERFLOW PATH ST STSTSTC C T V.P.FE SF E SFE SV.P. V.P.FE SLID LID LID / / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / // / / / / / / /D D D D D D D D 221 220 406 224 221 225 224 0.08 AC 221 2.18 AC 225 1.30 AC 212 0.68 AC 220 0.52 AC 406 0.11 AC EAST TRILBY ROAD CAND L E W O O D D RI V E BRITTANY DRIVEAUTUMN RIDGE DRIVEEXISTING STORM DRAINEXISTING STORM DRAIN EXISTING STORM DRAIN EXISTING STORM DRAIN EXISTING INLET EXISTING INLET EXISTING INLET EXISTING INLET EXISTING INLET FOR DRAINAGE REVIEW ONLY NOT FOR CONSTRUCTION CALL 2 BUSINESS DAYS IN ADVANCE BEFORE YOU DIG, GRADE, OR EXCAVATE FOR THE MARKING OF UNDERGROUND MEMBER UTILITIES. CALL UTILITY NOTIFICATION CENTER OF COLORADO Know what'sbelow. before you dig.Call R DR1 HISTORIC DRAINAGE EXHIBITX A 1.62 AC LEGEND: EXISTING STORM SEWER EXISTING CONTOUR EXISTING CURB & GUTTER PROPERTY BOUNDARY EXISTING INLET ADESIGN POINT FLOW ARROW DRAINAGE BASIN LABEL DRAINAGE BASIN BOUNDARY PROPOSED SWALE SECTION 11 NOTES: 1.REFER TO THE FINAL DRAINAGE LETTER AND LID REPORT FOR FORTY-THREE PRIME BY NORTHERN ENGINEERING DATED 7/28/2021, AND THE FINAL DRAINAGE AND EROSION CONTROL REPORT FOR PROVINCETOWNE PUD FILING TWO, DATED MARCH 22, 2001 BY MANHARD CONSULTING, LTD., FOR ADDITIONAL 2.THE NATURAL HABITAT BUFFER ZONE IS INTENDED TO BE MAINTAINED IN A NATIVE LANDSCAPE. PLEASE SEE SECTION 3.4.1 OF LAND USE CODE FOR ALLOWABLE USES WITHIN THE NATURAL HABITAT BUFFER ZONE. EXISTING PLANNEDCOMPOSITE % IMPERVIOUSNESS Basin ID Basin Area (ac)Composite % Imperv. 100-year Composite Runoff Coefficient 212 0.68 33%0.71 220 0.52 45%0.74 221 2.18 45%0.74 224 0.08 96%1.00 225 1.30 39%0.73 406 0.11 45%0.74 Total Site 4.87 42.6%0.56 SheetFORTY-THREE PRIMEThese drawings areinstruments of serviceprovided by NorthernEngineering Services, Inc.and are not to be used forany type of constructionunless signed and sealed bya Professional Engineer inthe employ of NorthernEngineering Services, Inc.NOT FOR CONSTRUCTIONREVIEW SETENGINEERNGIEHTRONRNFORT COLLINS: 301 North Howes Street, Suite 100, 80521GREELEY: 820 8th Street, 80631970.221.4158northernengineering.comof 18 NORTH