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HomeMy WebLinkAbout09_AppendixAFlowRatesPondSizingAndSpreadCalcsAppendix A – Flow Rates, Pond Sizing, and Spread Calculations 0.74 0.50 0.35 0.20 0.67 Note: Coefficients obtained from CoB Design Standards Table I-1 BASIN 1 Post-Development Weighted C-Value (Cw) Area Area Runoff (sqft)(Acres) Coefficient Calculations Compsosite R.O.W. 29697.02 0.68 0.74 0.50 Dense Residential 40009.93 0.92 0.50 0.46 Open Space 0.00 0.00 0.20 0.00 Alley R.O.W. 0.00 0.00 0.67 0.00 Fallon Appartments 0.00 0.00 0.50 0.00 Totals 69706.95 1.60 0.96 Cw =0.60 BASIN 2 Post-Development Weighted C-Value (Cw) Area Area Runoff (sqft)(Acres) Coefficient Calculations Composite R.O.W. 59411.59 1.36 0.74 1.01 Dense Residential 163039.8 3.74 0.50 1.87 Open Space 9298.07 0.21 0.20 0.04 Alley R.O.W. 25558.59 0.59 0.67 0.39 Fallon Appartments 12399 0.28 0.50 0.14 Totals 269707.07 6.19 3.46 Cw =0.56 BASIN 3 Post-Development Weighted C-Value (Cw) Area Area Runoff (sqft)(Acres) Coefficient Calculations Composite R.O.W. 12345.62 0.28 0.74 0.21 Dense Residential 16084.35 0.37 0.50 0.18 Open Space 1353.02 0.03 0.20 0.01 Alley R.O.W. 0 0.00 0.67 0.00 Totals 29782.99 0.68 0.40 Cw =0.59 BASIN 4 Post-Development Weighted C-Value (Cw) Area Area Runoff (sqft)(Acres) Coefficient Calculations Composite R.O.W. 3696.39 0.08 0.74 0.06 Dense Residential 3589.14 0.08 0.50 0.04 Open Space 1124.99 0.03 0.20 0.01 Alley R.O.W. 0 0.00 0.67 0.00 Totals 8410.52 0.19 0.11 Cw =0.57 MAJOR SUBDIVISION Weighted Runoff Coefficients MAY FLY TOWNHOMES Composite R.O.W. Dense Residential Alley R.O.W. Open Space Medium Residential L:\203430\Computations\MAYFLY TOWNHOMES\Stormwater Calculations MAYFLY TOWNHOMES BASIN 5 Post-Development Weighted C-Value (Cw) Area Area Runoff (sqft)(Acres) Coefficient Calculations Composite R.O.W. 59791.92 1.37 0.74 1.02 Dense Residential 3046.93 0.07 0.50 0.03 Medium Residential 46492.38 1.07 0.35 0.37 Alley R.O.W. 0 0.00 0.67 0.00 Totals 109331.23 2.51 1.42 Cw =0.57 BASIN 6 Post-Development Weighted C-Value (Cw) Area Area Runoff (sqft)(Acres) Coefficient Calculations Composite R.O.W. 12317.93 0.28 0.74 0.21 Dense Residential 0 0.00 0.50 0.00 Open Space 0 0.00 0.20 0.00 Alley R.O.W. 0 0.00 0.67 0.00 Totals 12317.93 0.28 0.21 Cw =0.74 BASIN 7 Post-Development Weighted C-Value (Cw) Area Area Runoff (sqft)(Acres) Coefficient Calculations Composite R.O.W. 4094.28 0.09 0.74 0.07 Dense Residential 0 0.00 0.50 0.00 Open Space 0 0.00 0.20 0.00 Alley R.O.W. 0 0.00 0.67 0.00 Totals 4094.28 0.09 0.07 Cw =0.74 BASIN 8 Post-Development Weighted C-Value (Cw) Area Area Runoff (sqft)(Acres) Coefficient Calculations Composite R.O.W. 8772.43 0.20 0.74 0.15 Dense Residential 0 0.00 0.50 0.00 Open Space 0 0.00 0.20 0.00 Alley R.O.W. 0 0.00 0.67 0.00 Totals 8772.43 0.20 0.15 Cw =0.74 BASIN 9 Post-Development Weighted C-Value (Cw) Area Area Runoff (sqft)(Acres) Coefficient Calculations Compsosite R.O.W. 26608.39 0.61 0.74 0.45 Dense Residential 57235.29 1.31 0.50 0.66 Open Space 5170.85 0.12 0.20 0.02 Alley R.O.W. 15988.09 0.37 0.67 0.25 Fallon Appartments 13770.35 0.32 0.50 0.16 Totals 118772.97 2.73 1.54 Cw =0.56 L:\203430\Computations\MAYFLY TOWNHOMES\Stormwater Calculations MAYFLY TOWNHOMES Equations Used: Qp = C i A (Modified Rational Method) i = a * (DURATION) ^ -(b) (City of Bozeman) Overland Flow tc=((1.8)*(1.1-C)*(D^(1/2)))/(S^(1/3)) (City of Bozeman) Gutter Flow V=3.28*k*(S^(1/2), where k=0.618 (paved) (FHWA HEC 22, Eqn 3-4) BASIN 1 Basin Area (ac): 1.60 Storm Event Intensity Post-Dev C (weighted): 0.60 (yr) (in/hr)A B Overland Distance (ft): 14 2 1.20 0.36 0.6 Overland Slope (%): 1.0 5 1.87 0.52 0.64 Gutter Flow Distance (ft): 710.0 10 2.35 0.64 0.65 Gutter Flow Slope (%): 1.5 25 2.81 0.78 0.64 Post-Dev. Tc (min): 8.1 50 3.44 0.92 0.66 100 3.86 1.01 0.67 Storm Event (yr): 2 10 25 100 Storm Coeff. A: 0.36 0.64 0.78 1.01 Storm Coeff. B:0.60 0.65 0.64 0.67 Composite C: 0.60 0.60 0.60 0.60 Storm Intensity (in/hr): 1.20 2.35 2.81 3.86 Post-Dev Qp (cfs):1.15 2.26 2.70 3.72 BASIN 2 Basin Area (ac): 6.19 Storm Event Intensity Post-Dev C (weighted): 0.56 (yr) (in/hr)A B Overland Distance (ft): 215 2 0.70 0.36 0.6 Overland Slope (%): 1.0 5 1.06 0.52 0.64 Gutter Flow Distance (ft): 810.0 10 1.32 0.64 0.65 Gutter Flow Slope (%): 1.5 25 1.59 0.78 0.64 Post-Dev. Tc (min): 19.7 50 1.92 0.92 0.66 100 2.13 1.01 0.67 Storm Event (yr): 2 10 25 100 Storm Coeff. A: 0.36 0.64 0.78 1.01 Storm Coeff. B:0.60 0.65 0.64 0.67 Composite C: 0.56 0.56 0.56 0.56 Storm Intensity (in/hr): 0.70 1.32 1.59 2.13 Post-Dev Qp (cfs):2.43 4.56 5.50 7.36 BASIN 3 Basin Area (ac): 0.68 Storm Event Intensity Post-Dev C (weighted): 0.59 (yr) (in/hr)A B Overland Distance (ft): 60 2 1.02 0.36 0.6 Overland Slope (%): 1.0 5 1.57 0.52 0.64 Gutter Flow Distance (ft): 300.0 10 1.97 0.64 0.65 Gutter Flow Slope (%): 0.5 25 2.36 0.78 0.64 Post-Dev. Tc (min): 10.7 50 2.88 0.92 0.66 100 3.21 1.01 0.67 Storm Event (yr): 2 10 25 100 Storm Coeff. A: 0.36 0.64 0.78 1.01 Storm Coeff. B:0.60 0.65 0.64 0.67 Composite C: 0.59 0.59 0.59 0.59 Storm Intensity (in/hr): 1.02 1.97 2.36 3.21 Post-Dev Qp (cfs):0.41 0.79 0.94 1.29 BASIN 4 Basin Area (ac): 0.19 Storm Event Intensity Post-Dev C (weighted): 0.57 (yr) (in/hr)A B Overland Distance (ft): 60 2 1.16 0.36 0.6 Overland Slope (%): 1.0 5 1.81 0.52 0.64 Gutter Flow Distance (ft): 95.0 10 2.27 0.64 0.65 Gutter Flow Slope (%): 0.5 25 2.71 0.78 0.64 Post-Dev. Tc (min): 8.6 50 3.33 0.92 0.66 100 3.72 1.01 0.67 Storm Event (yr): 2 10 25 100 Storm Coeff. A: 0.36 0.64 0.78 1.01 Storm Coeff. B:0.60 0.65 0.64 0.67 Composite C: 0.57 0.57 0.57 0.57 Storm Intensity (in/hr): 1.16 2.27 2.71 3.72 Post-Dev Qp (cfs):0.13 0.25 0.30 0.41 MAY FLY TOWNHOMES POST-DEVELOPMENT SUB BASIN FLOWS MAJOR SUBDIVISION Storm Coeff. (i) Storm Coeff. (i) Storm Coeff. (i) Storm Coeff. (i) L:\203430\Computations\MAYFLY TOWNHOMES\Stormwater Calculations MAYFLY TOWNHOMES BASIN 5 Basin Area (ac): 2.51 Storm Event Intensity Post-Dev C (weighted): 0.57 (yr) (in/hr)A B Overland Distance (ft): 10 2 1.22 0.36 0.6 Overland Slope (%): 0.8 5 1.91 0.52 0.64 Gutter Flow Distance (ft): 685.0 10 2.40 0.64 0.65 Gutter Flow Slope (%): 1.5 25 2.86 0.78 0.64 Post-Dev. Tc (min): 7.9 50 3.52 0.92 0.66 100 3.94 1.01 0.67 Storm Event (yr): 2 10 25 100 Storm Coeff. A: 0.36 0.64 0.78 1.01 Storm Coeff. B:0.60 0.65 0.64 0.67 Composite C: 0.57 0.57 0.57 0.57 Storm Intensity (in/hr): 1.22 2.40 2.86 3.94 Post-Dev Qp (cfs):1.74 3.42 4.08 5.61 BASIN 6 Basin Area (ac): 0.28 Storm Event Intensity Post-Dev C (weighted): 0.74 (yr) (in/hr)A B Overland Distance (ft): 10 2 1.40 0.36 0.6 Overland Slope (%): 0.4 5 2.21 0.52 0.64 Gutter Flow Distance (ft): 300.0 10 2.78 0.64 0.65 Gutter Flow Slope (%): 0.5 25 3.31 0.78 0.64 Post-Dev. Tc (min): 6.3 50 4.09 0.92 0.66 100 4.59 1.01 0.67 Storm Event (yr): 2 10 25 100 Storm Coeff. A: 0.36 0.64 0.78 1.01 Storm Coeff. B:0.60 0.65 0.64 0.67 Composite C: 0.74 0.74 0.74 0.74 Storm Intensity (in/hr): 1.40 2.78 3.31 4.59 Post-Dev Qp (cfs):0.29 0.58 0.69 0.96 BASIN 7 Basin Area (ac): 0.09 Storm Event Intensity Post-Dev C (weighted): 0.74 (yr) (in/hr)A B Overland Distance (ft): 10 2 1.92 0.36 0.6 Overland Slope (%): 1.0 5 3.11 0.52 0.64 Gutter Flow Distance (ft): 140.0 10 3.93 0.64 0.65 Gutter Flow Slope (%): 0.5 25 4.66 0.78 0.64 Post-Dev. Tc (min): 3.7 50 5.81 0.92 0.66 100 6.56 1.01 0.67 Storm Event (yr): 2 10 25 100 Storm Coeff. A: 0.36 0.64 0.78 1.01 Storm Coeff. B:0.60 0.65 0.64 0.67 Composite C: 0.74 0.74 0.74 0.74 Storm Intensity (in/hr): 1.92 3.93 4.66 6.56 Post-Dev Qp (cfs):0.13 0.27 0.32 0.46 BASIN 8 Basin Area (ac): 0.20 Storm Event Intensity Post-Dev C (weighted): 0.74 (yr) (in/hr)A B Overland Distance (ft): 10 2 1.66 0.36 0.6 Overland Slope (%): 1.0 5 2.65 0.52 0.64 Gutter Flow Distance (ft): 180.0 10 3.35 0.64 0.65 Gutter Flow Slope (%): 0.3 25 3.98 0.78 0.64 Post-Dev. Tc (min): 4.7 50 4.94 0.92 0.66 100 5.56 1.01 0.67 Storm Event (yr): 2 10 25 100 Storm Coeff. A: 0.36 0.64 0.78 1.01 Storm Coeff. B:0.60 0.65 0.64 0.67 Composite C: 0.74 0.74 0.74 0.74 Storm Intensity (in/hr): 1.66 3.35 3.98 5.56 Post-Dev Qp (cfs):0.25 0.50 0.59 0.83 BASIN 9 Basin Area (ac): 2.73 Storm Event Intensity Post-Dev C (weighted): 0.56 (yr) (in/hr)A B Overland Distance (ft): 185 2 0.75 0.36 0.6 Overland Slope (%): 1.0 5 1.14 0.52 0.64 Gutter Flow Distance (ft): 661.0 10 1.42 0.64 0.65 Gutter Flow Slope (%): 1.5 25 1.71 0.78 0.64 Post-Dev. Tc (min): 17.6 50 2.07 0.92 0.66 100 2.30 1.01 0.67 Storm Event (yr): 2 10 25 100 Storm Coeff. A: 0.36 0.64 0.78 1.01 Storm Coeff. B:0.60 0.65 0.64 0.67 Composite C: 0.56 0.56 0.56 0.56 Storm Intensity (in/hr): 0.75 1.42 1.71 2.30 Post-Dev Qp (cfs):1.16 2.19 2.63 3.53 Storm Coeff. (i) Storm Coeff. (i) Storm Coeff. (i) Storm Coeff. (i) Storm Coeff. (i) L:\203430\Computations\MAYFLY TOWNHOMES\Stormwater Calculations MAYFLY TOWNHOMES MAY FLY TOWNHOMES MAJOR SUBDIVISION SDI FLOWS Storm Drain Inlet ID#Basin 10-Yr Flow (cfs) 25-Yr Flow (cfs) 100-Yr Flow (cfs) CB-2F Sag Basin 1 2.26 2.70 3.72 CB-1B On Grade Basin 2 4.56 5.50 7.36 CB-1C Sag Basin 3 0.79 0.94 1.29 CB-2H On Grade Basin 4 0.25 0.30 0.41 CB-1A On Grade Basin 5 3.42 4.08 5.61 CB-1D Sag Basin 6 0.58 0.69 0.96 CB-2I On Grade Basin 7 0.27 0.32 0.46 CB-2G Sag Basin 8 0.50 0.59 0.83 SDI 1 On Grade Basin 9 2.19 2.63 3.53 Label Inlet TypeDischarge (ft³/s)Bypass From NodeDischarge + Bypass (ft3/s)Spread (ft)Gutter Width (ft)Road Slope (%)Gutter Cross Slope (%)Road Cross Slope (%)Grate Width (ft)Grate Length (ft) Grate TypeCurb Opening Length (ft)Opening Height (ft)Inlet Efficiency (%)Water Depth at Curb (in)Intercepted Flow (ft3/s)Bypass (ft3/s)CB-2F - 25YR SAG 2.70 SDI 1 3.66 13.2 1.5 1.20% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 100 5.3 3.66 0CB-2F - 100YR SAG 3.72 SDI 1 5.18 16.4 1.5 1.20% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 100 6.5 5.18 0CB-1B - 25YR ON GRADE 5.50 8.9 1.5 1.50% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 51.02 3.8 2.81 2.69CB-1B - 100YR ON GRADE 7.36 10 1.5 1.50% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 46.52 4.2 3.42 3.94CB-1C - 25YR SAG 0.94 CB-2H 0.96 5.8 1.5 0.50% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 100 2.7 0.96 0.00CB-1C - 100YR SAG 1.29 CB-2H 1.33 7.1 1.5 0.50% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 100 3.1 1.33 0.00CB-1D - 25YR SAG 0.69 CB-2I 0.71 4.9 1.5 0.50% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 100 2.4 0.71 0.00CB-1D - 100YR SAG 0.96 CB-2I 1.01 6 1.5 0.50% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 100 2.8 1.01 0.00CB-2I - 25YR ON GRAGE 0.32 3.3 1.5 0.50% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 93.57 1.8 0.30 0.02CB-2I - 100YR ON GRADE 0.46 3.9 1.5 0.50% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 89.44 2 0.41 0.05CB-2H - 25YR ON GRADE 0.30 3.2 1.5 0.50% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 94.22 1.7 0.28 0.02CB-2H - 100YR ON GRADE 0.41 3.7 1.5 0.50% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 90.83 1.9 0.37 0.04CB-1A - 25YR ON GRADE 4.08 7.9 1.5 1.50% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 55.90 3.4 2.28 1.80CB-1A - 100YR ON GRADE 5.61 8.9 1.5 1.50% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 50.71 3.8 2.84 2.77CB-2G - 25YR SAG 0.59 4.4 1.5 1.20% 6.25 3.00% 1.5 3 Curved Vaned 3 0.5 100 2.2 0.59 0CB-2G - 100YR SAG 0.83 5.4 1.5 1.20% 6.25 3.00% 1.5 3 Curved Vaned 3 0.5 100 2.5 0.83 0SDI 1 - 25YR ON GRADE 2.63 6.6 1.5 1.55% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 63.59 2.9 1.67 0.96SDI 1 - 100YR ON GRADE 3.53 7.3 1.5 1.55% 6.25% 3.00% 1.5 3 Curved Vaned 3 0.5 58.52 3.2 2.07 1.46MAY FLY TOWNHOMESSTORM DRAIN INLET SPREAD CALCSMAJOR SUBDIVISION Required Detention Pond Sizing Contributing Area C Area (ft2)C*Area Basin 2 ROW 0.74 59411.59 43965 Open Space 0.2 9298.07 1860 High Density Residential 0.5 163039.8 81520 Fallon Apartments 0.5 12399 6200 Alley ROW 0.67 25558.59 17124 Basin 3 ROW 0.74 12345.62 9136 Open Space 0.2 1353.02 271 High Density Residential 0.5 16084.35 8042 Basin 5 ROW 0.74 59791.92 44246 High Density Residential 0.50 3046.93 1523 Medium Residential 0.35 46492.38 16272 Basin 6 ROW 0.74 12317.93 9115 Totals 421139.2 239273 A = Area (acres)9.67 C = Weighted C Factor 0.57 Discharge Rate (cfs) =1.43 * i = 0.64x-.65 (COB DESIGN STANDARD, Fig. I-3 , 10 yr Storm) Q = CiA Duration Duration Intensity Q Runoff Release Required min hr in/hr cfs Volume Volume Storage 40 0.67 0.83 4.58 10981 944 10038 41 0.68 0.82 4.50 11077 1030 10047 42 0.70 0.81 4.43 11171 1115 10055 43 0.72 0.79 4.37 11263 1201 10062 44 0.73 0.78 4.30 11354 1287 10067 45 0.75 0.77 4.24 11444 1373 10071 46 0.77 0.76 4.18 11532 1459 10073 47 0.78 0.75 4.12 11619 1544 10075 48 0.80 0.74 4.06 11705 1630 10075 49 0.82 0.73 4.01 11790 1716 10074 50 0.83 0.72 3.96 11873 1802 10072 51 0.85 0.71 3.91 11956 1888 10068 52 0.87 0.70 3.86 12038 1973 10064 53 0.88 0.69 3.81 12118 2059 10059 54 0.90 0.69 3.76 12198 2145 10053 * From Norton Ranch Phase 4 Design Report, C&H Engineering MAY FLY TOWNHOMES MAJOR SUBDIVISION Required Detention Pond 1 Volume Q = CIA V = 22194Q C = Weighted C Factor 0.57 I = Intensity (in/hr) 0.0811 (10 yr, 24 hr storm) A = Area (acres) 9.67 Q = Runoff (cfs) 0.446 V = Required Vol (ft3)9887 Note: A 10-year 24-hour event produces 0.5" of rain after 6.165 hours (I = 0.64*(24)^-.65 = 0.0811 in/hr --> 0.5in/0.0811 in/hr = 6.165 hours) Note: The required volume was calculated using the 6.165 hours it takes to rain 0.5" (6.165 hr * 60 min/hr * 60 sec/min = 22194 sec. --> V = 22194 sec * .0446 cfs = 9887 cf) Note: The outlet structure will not release any water unitl the initial 9,887 CF of runoff from the first 0.5" of rain has been retained. REQUIRED STORAGE FOR FIRST 0.5" OF RAIN FROM 24-HOUR STORM EVENT POND 1 Required Detention Pond 2 Sizing Contributing Area C Area (ft 2) C*Area Norton Phase 2A Existing Development 0.50 241552 120776 * Norton Phase Phase 4 Remainder ROW 0.74 54523 40347 * Park 0.20 35811 7162 * High Density Residential 0.50 91442 45721 * Basin 1 ROW 0.74 29697.02 21976 High Density Residential 0.50 37279.75 18640 Open Space 0.20 2730.00 546 Basin 4 ROW 0.74 3696.39 2735 Open Space 0.2 1124.99 225 High Density Residential 0.5 3589.14 1795 Basin 7 ROW 0.74 4094.28 3030 Basin 8 ROW 0.74 8772.43 6492 Basin 9 R.O.W.0.74 26608.39 19690 Dense Residential 0.50 57235.29 28618 Open Space 0.20 5170.85 1034 Alley R.O.W.0.67 15988.09 10712 Fallon Appartments 0.50 13770.35 6885 Totals 633084.969 336383 A = Area (acres)14.53 C = Weighted C Factor 0.53 Discharge Rate (cfs) =1.91 * i = 0.64x-.65 (COB DESIGN STANDARD, Fig. I-3 , 10 yr Storm) Q = CiA Duration Duration Intensity Q Runoff Release Required min hr in/hr cfs Volume Volume Storage 45 0.75 0.77 5.96 16088 1834 14254 46 0.77 0.76 5.87 16212 1948 14264 47 0.78 0.75 5.79 16335 2063 14272 48 0.80 0.74 5.71 16455 2177 14278 49 0.82 0.73 5.64 16575 2292 14283 50 0.83 0.72 5.56 16692 2407 14286 51 0.85 0.71 5.49 16808 2521 14287 52 0.87 0.70 5.42 16923 2636 14287 53 0.88 0.69 5.36 17036 2750 14286 54 0.90 0.69 5.29 17148 2865 14283 55 0.92 0.68 5.23 17259 2980 14279 56 0.93 0.67 5.17 17368 3094 14273 57 0.95 0.66 5.11 17476 3209 14267 58 0.97 0.65 5.05 17582 3323 14259 59 0.98 0.65 5.00 17688 3438 14250 * From Norton Ranch Phase 4 Stormwater Design Report, C&H Engineering MAY FLY TOWNHOMES MAJOR SUBDIVISION Required Detention Pond 2 Volume Q = CIA V = 22194Q C = Weighted C Factor 0.53 I = Intensity (in/hr) 0.0811 (10 yr, 24 hr storm) A = Area (acres) 14.53 Q = Runoff (cfs) 0.626 V = Required Vol (ft3)13900 Note: A 10-year 24-hour event produces 0.5" of rain after 6.165 hours (I = 0.64*(24)^-.65 = 0.0811 in/hr --> 0.5in/0.0811 in/hr = 6.165 hours) Note: The required volume was calculated using the 6.165 hours it takes to rain 0.5" (6.165 hr * 60 min/hr * 60 sec/min = 22194 sec. --> V = 22194 sec * .0446 cfs = 9887 cf) Note: The outlet structure will not release any water unitl the initial 13,900 CF of runoff from the first 0.5" of rain has been retained. REQUIRED STORAGE FOR FIRST 0.5" OF RAIN FROM 24-HOUR STORM EVENT POND 2