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Home My WebLink AboutRIGDEN FARM FILING SIX, TRACT Z, MULTI-FAMILY - PDP - PDP140009 - REPORTS - DRAINAGE REPORTProject: Tract Z Multi-Family Project Number: 13-2449 Basin Area (SF) AREA (AC) Landscape Paved Roof Percent Impervious A1 42,151 0.97 9,583 19,166 14,810 77% A2 20,828 0.48 1,861 11,160 7,807 87% A3 32,705 0.75 22,938 1,763 8,004 27% A4 17,156 0.39 10,122 464 6,570 37% A5 15,831 0.36 9,979 1,116 4,736 34% Total 128,671 2.95 54,483 33,669 41,927 55.5% Proposed Design 6/12/2014 Olsson Associates Copyright 2014 A1 A4 A3 A2 A5 Project Title: Catchment ID: Illustration Instructions: For each catchment subarea, enter values for A and C. Subarea Area Runoff Product ID acres Coeff. A C* CA input input input output Pavement 0.43 100.00 43.00 Roof 0.36 90.00 32.40 Landscape 0.18 0.00 0.00 Porous 40.00 0.00 Sum: 0.97 Sum: 75.40 Area-Weighted Runoff Coefficient (sum CA/sum A) = 77.73 *See sheet "Design Info" for inperviousness-based runoff coefficient values. Area-Weighting for Runoff Coefficient Calculation 132449_Runoff Calcs, Weighted C 6/12/2014, 3:24 PM Project Title: Catchment ID: I. Catchment Hydrologic Data Catchment ID = A1 Area = 0.97 Acres Percent Imperviousness = 75.40 % NRCS Soil Type = B A, B, C, or D II. Rainfall Information I (inch/hr) = C1 * P1 /(C2 + Td)^C3 Design Storm Return Period, Tr = 2 years (input return period for design storm) C1 = 28.50 (input the value of C1) C2= 10.00 (input the value of C2) C3= 0.786 (input the value of C3) P1= 0.85 inches (input one-hr precipitation--see Sheet "Design Info") III. Analysis of Flow Time (Time of Concentration) for a Catchment Runoff Coefficient, C = 0.51 Overide Runoff Coefficient, C = (enter an overide C value if desired, or leave blank to accept calculated C.) 5-yr. Runoff Coefficient, C-5 = 0.54 Overide 5-yr. Runoff Coefficient, C = (enter an overide C-5 value if desired, or leave blank to accept calculated C-5.) Illustration NRCS Land Heavy Tillage/ Short Nearly Grassed Type Meadow Field Pasture/ Bare Swales/ Lawns Ground Waterways Conveyance 2.5 5 7 10 15 Calculations: Reach Slope Length 5-yr NRCS Flow Flow ID S L Runoff Convey- Velocity Time Coeff ance V Tf ft/ft ft C-5 fps minutes input input output input output output Overland 0.0100 25 0.54 N/A 0.08 5.02 1 0.0100 359 20.00 2.00 2.99 2 3 4 5 384 Computed Tc = 8.01 Regional Tc = 12.13 User-Entered Tc = 8.01 IV. Peak Runoff Prediction Rainfall Intensity at Computed Tc, I = 2.51 inch/hr Peak Flowrate, Qp = 1.24 cfs Rainfall Intensity at Regional Tc, I = 2.13 inch/hr Peak Flowrate, Qp = 1.06 cfs Rainfall Intensity at User-Defined Tc, I = 2.51 inch/hr Peak Flowrate, Qp = 1.24 cfs (Sheet Flow) 20 Shallow Paved Swales Sum CALCULATION OF A PEAK RUNOFF USING RATIONAL METHOD Rigden Farm Filing Six, Tract Z MF A1 Paved Areas & 132449_Runoff Calcs, Tc and PeakQ 6/12/2014, 3:25 PM Sheet 1 of 2 Designer: Company: Date: Project: Location: 1. Basin Storage Volume A) Effective Imperviousness of Tributary Area, Ia Ia = 78.0 % (100% if all paved and roofed areas upstream of rain garden) B) Tributary Area's Imperviousness Ratio (i = Ia/100) i = 0.780 C) Water Quality Capture Volume (WQCV) for a 12-hour Drain Time WQCV = 0.25 watershed inches (WQCV= 0.8 * (0.91* i3 - 1.19 * i2 + 0.78 * i) D) Contributing Watershed Area (including rain garden area) Area = 42,051 sq ft E) Water Quality Capture Volume (WQCV) Design Volume VWQCV = cu ft Vol = (WQCV / 12) * Area F) For Watersheds Outside of the Denver Region, Depth of d6 = 0.43 in Average Runoff Producing Storm G) For Watersheds Outside of the Denver Region, VWQCV OTHER = 886.6 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 = 6 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 = 591 sq ft D) Actual Flat Surface Area AActual = 1710 sq ft E) Area at Design Depth (Top Surface Area) ATop = 2165 sq ft F) Rain Garden Total Volume VT= 969 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 = 2.0 ft Volume to the Center of the Orifice ii) Volume to Drain in 12 Hours Vol12 = 887 cu ft iii) Orifice Diameter, 3/8" Minimum DO = 0.69 in Design Procedure Form: Rain Garden (RG) SSZ OLSSON ASSOCIATES October 1, 2014 RIGDEN FARM TRACT Z FORT COLLINS, CO Choose One Choose One 18" Rain Garden Growing Media Other (Explain): YES NO Rain Garden.xlsm, RG 10/1/2014, 12:07 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? 6. Inlet / Outlet Control A) Inlet Control 7. Vegetation 8. Irrigation NO SPRINKLER HEADS ON FLAT SURFACE A) Will the rain garden be irrigated? Notes: Design Procedure Form: Rain Garden (RG) SSZ OLSSON ASSOCIATES October 1, 2014 RIGDEN FARM TRACT Z 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 Rain Garden.xlsm, RG 10/1/2014, 12:07 PM Sheet 1 of 2 Designer: Company: Date: Project: Location: 1. Type of Permeable Pavement Section A) What type of section of permeable pavement is used? (Based on the land use and activities, proximity to adjacent structures and soil characteristics.) B) What type of wearing course? 2. Required Storage Volume A) Effective Imperviousness of Area Tributary to Permeable Pavement, Ia Ia = 87.0 % B) Tributary Area's Imperviousness Ratio (I = Ia / 100) i = 0.870 C) Tributary Watershed Area ATotal = 20,828 sq ft (including area of permeable pavement system) D) Area of Permeable Pavement System APPS = 6,967 sq ft (Minimum recommended permeable pavement area = 6314 sq ft) E) Impervious Tributary Ratio RT = 1.7 (Contributing Imperviuos Area / Permeable Pavement Ratio) F) Water Quality Capture Volume (WQCV) Based on 12-hour Drain Time WQCV = 524 cu ft (WQCV = (0.8 * (0.91 * i3 - 1.19 * i2 + 0.78 * i) / 12) * Area) G) Is flood control volume being added? H) Total Volume Needed VTotal = cu ft 3. Depth of Reservoir A) Minimum Depth of Reservoir Dmin = 6.0 inches (Minimum recommended depth is 6 inches) B) Is the slope of the reservoir/subgrade interface equal to 0%? C) Porosity (Porous Gravel Pavement < 0.3, Others < 0.40) P = 0.40 D) Slope of the Base Course/Subgrade Interface S = 0.020 ft / ft E) Length Between Lateral Flow Barriers (max = 18.79 ft.) L = 18.8 ft F) Volume Provided Based on Depth of Base Course V = 639 cu ft Flat or Stepped: V = P * ((Dmin-1)/12) * Area Sloped: V = P * [(Dmin - (Dmin - 6*SL-1)) / 12] * Area Volume assumes uniform slope & lateral flow barrier spacing. Calculate the volume of each cell individually when this varies. 4. Lateral Flow Barriers A) Type of Lateral Flow Barriers B) Number of Permeable Pavement Cells Cells = 10 5. Perimeter Barrier A) Is a perimeter barrier provided on all sides of the pavement system? (Recommeded for PICP, concrete grid pavement, or for any no-infiltration section.) Rigden Farm Filing Six, Tract Z MF Fort Collins, Colorado Design Procedure Form: Permeable Pavement Systems (PPS) SSZ Olsson Associates June 12, 2014 Choose One No Infiltration Partial Infiltration Section Full Infiltration Section Choose One YES NO Choose One YES- Flat or Stepped Installation NO- Sloped Installation Choose One Sheet 2 of 2 Designer: Company: Date: Project: Location: 6. Filter Material and Underdrain System A) Is the underdrain placed below a 6-inch thick layer of CDOT Class C filter material? B) Diameter of Slotted Pipe (slot dimensions per Table PPs-2) C) Distance from the Lowest Elevation of the Storage Volume y = 0.7 ft (i.e. the bottom of the base course to the center of the orifice) 7. Impermeable Geomembrane Liner and Geotextile Separator Fabric A) Is there a minimum 30 mil thick impermeable PVC geomembrane liner on the bottom and sides of the basin, extending up to the top of the base course? B) CDOT Class B Separator Fabric 8. Outlet (Assumes each cell has similar area, subgrade slope, and length between lateral barriers (unless subgrade is flat). Calculate cells individually where this varies.) A) Depth of WQCV in the Reservoir DWQCV = 4.50 inches (Elevation of the Flood Control Outlet) B) Diameter of Orifice for 12-hour Drain Time DOrifice = 0.66 inches (Use a minimum orifice diameter of 3/8-inches) Notes: Rigden Farm Filing Six, Tract Z MF Design Procedure Form: Permeable Pavement Systems (PPS) SSZ Olsson Associates June 12, 2014 Fort Collins, Colorado Choose One YES NO Choose One 4-inch 6-inch Choose One Choose One YES NO Placed above the liner Placed above and below the liner N/A Permeable Pavement Calc2.0, PPS 6/12/2014, 3:27 PM RAIN GARDEN NOTES FIGURE 1 PERMEABLE PAVEMENT UNDERDRAIN PLAN FORT COLLINS 2014 R EXHIBIT TEL 970.461.7733 Loveland, CO 80538 Suite 160 RAIN GARDEN 5285 McWhinney Boulevard OUTLET STRUCTURE DETAIL R 2 EXHIBIT 1 BIORETENTION- RAIN GARDEN DETAILS FORT COLLINS 2014 URBAN DRAINAGE AND FLOOD CONTROL DISTRICT R BUILDING #3 5-PLEX BUILDING #4 3-PLEX BUILDING #7 8-PLEX CELL 1 CELL 2 CELL 3 CELL 4 CELL 5 CELL 6 CELL 7 CELL 8 CELL 9 CELL 10 C C PERMEABLE PAVEMENT NOTES FIGURE 1 PERMEABLE PAVEMENT UNDERDRAIN PLAN FORT COLLINS 2014 R EXHIBIT TEL 970.461.7733 Loveland, CO 80538 Suite 160 PERMEABLE PAVEMENT 5285 McWhinney Boulevard UNDERDRAIN DETAIL R 1 PERMEABLE PAVEMENT SECTION D-D PERMEABLE PAVEMENT SECTION C-C EXHIBIT TEL 970.461.7733 Loveland, CO 80538 Suite 160 PERMEABLE PAVEMENT 5285 McWhinney Boulevard CROSS SECTIONS R 2 Concrete Walls PVC geomembrane installed normal to flow N/A- Flat installation Other (Describe): Choose One YES NO Choose One PICP Concrete Grid Pavement Pervious Concrete Porous Gravel Permeable Pavement Calc2.0, PPS 6/12/2014, 3:27 PM