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HomeMy WebLinkAboutCEQA23-0001 SD Calcs - 042423Job No.:20153 Client:GREG HOWELL Job Name:HICKS LANE (APN 007-010-054) STORMWATER DETENTION CALCULATIONS Date:04/24/23 1 of 10 Job No.20153 Client Howell Job Name Hicks Lane Stormwater Detention Calculations Chkd PWR Date 04/24/23 By Dustin Behne 1. Tributary Areas 1. Roof Surfaces (ac) =0.00 2. AC & hardscape (ac) =0.00 3. Gravel roads & parking (ac) =0.00 4. Landscape (ac) =1.85 Σ (ac) =1.85 2. Runoff Coefficient (Butte County Std. D-5) 1. Roof Surfaces C-Factor =0.95 2. AC & hardscape C-Factor =0.903. Gravel roads & parking C-Factor =0.80 4. Natural Landscape C-Factor =0.46 Overall Composite C =0.46 3. Time of Concentration A. Sheet Flow (Kinematic Wave Equation) (landscape area) Legend: Tt = Travel time (minutes) L = Length of flow path (ft) EL1 (ft) =88.2 S = Slope of flow (ft/ft) EL2 (ft) =87.4 n = Manning's roughness coefficient L (ft) =70.5 i = Design storm rainfall intensity (in/hr) S (ft/ft) =0.0113 n =0.15 i10 (in/hr) =1.47 i100 (in/hr) =3.18 Tt(10) (min) =12.6 Tt(100) (min) =9.2 B. Shallow Concentrated Flow (Upland Method) Pre-Development Conditions Tributary Area No. 1 10352 535393.0 Si nLTt= 2 of 10 Job No.20153 Client Howell Job Name Hicks Lane Stormwater Detention Calculations Chkd PWR Date 04/24/23 By Dustin Behne EL1 (ft) =87.4 Legend: EL2 (ft) =86.0 V = Flow velocity (fps) L (ft) =200 k = Intercept coefficient S (%) =0.7 S = Flow slope (%) k =0.213 L = Flow length (ft) V (fps) =0.58 Tt(10) (min) =5.7 Tt(100) (min) =5.7 C. Channel Flow EL1 (ft) =86.0 Legend: EL2 (ft) =83.9 Ku = Units conversion factor = 1.49 Ku =1.49 n = roughness coefficient n =0.03 R = Hydraulic radius (ft) R10 (ft) =0.1 L = Flow length (ft) R100 (ft) =0.2 S = Flow slope (ft/ft) L (ft) =236.0 V = Flow velocity (fps) S (ft/ft) =0.0089 Tt = Travel time (min) V10 (fps) =1.1 V100 (fps) =1.4 Tt(10) (min) =3.6 Tt(100) (min) =2.8 D. Total Time of Concentration Tc(10) (min) =,use 22 minutes Tc(100) (min) =,use 17 minutes 4. Rainfall Intensity (Butte County Std. 10.05-3.01) I10 = I100 = 5. Peak Design Flow Q10 (cfs) =1.25 Q100 (cfs) =2.70 3.18 21.8 17.7 1.47 AICQ**= 2128.3 kSV=V LTt60= 2132SRn KVu=V LTt60= 3 of 10 Job No.20153 Client Howell Job Name Hicks Lane Stormwater Detention Calculations Chkd PWR Date 04/24/23 By Dustin Behne 1. Tributary Areas 1. Roof Surfaces (ac) =0.04 2. AC & hardscape (ac) =0.05 3. Gravel roads & parking (ac) =1.33 4. Landscape (ac) =0.43 Σ (ac) =1.85 2. Runoff Coefficient (Butte County Std. D-5) 1. Roof Surfaces C-Factor =0.95 2. AC & hardscape C-Factor =0.90 3. Gravel roads & parking C-Factor =0.80 4. Natural Landscape C-Factor =0.46 Overall Composite C =0.73 3. Time of Concentration A. Sheet Flow (Kinematic Wave Equation) EL1 (ft) =89.0 Legend: EL2 (ft) =86.2 Tt = Travel time (minutes) L (ft) =275 L = Length of flow path (ft) S (ft/ft) =0.010 S = Slope of flow (ft/ft) n =0.011 n = Manning's roughness coefficient i10 (in/hr) =2.32 i = Design storm rainfall intensity (in/hr) i100 (in/hr) =3.78 Tt(10) (min) =5.1 Tt(100) (min) =4.2 Post-Development Conditions Tributary Area No. 1 10352 535393.0 Si nLTt= 4 of 10 Job No.20153 Client Howell Job Name Hicks Lane Stormwater Detention Calculations Chkd PWR Date 04/24/23 By Dustin Behne B.Basin Channel Flow EL1 (ft) =84.7 Legend: EL2 (ft) =84.3 Ku = Units conversion factor = 1.49 Ku =1.49 n = roughness coefficient n =0.03 R = Hydraulic radius (ft) R10 (ft) =L = Flow length (ft) R100 (ft) =0.1 S = Flow slope (ft/ft) L (ft) =76.0 V = Flow velocity (fps) S (ft/ft) =0.0053 Tt = Travel time (min) V10 (fps) = V100 (fps) = Tt(10) (min) =1.8 Tt(100) (min) =1.6 C.Swale Channel Flow EL1 (ft) =84.3 Legend: EL2 (ft) =83.4 Ku = Units conversion factor = 1.49 Ku =1.49 n = roughness coefficient n =0.03 R = Hydraulic radius (ft) R10 (ft) =L = Flow length (ft) R100 (ft) =0.3 S = Flow slope (ft/ft) L (ft) =145.0 V = Flow velocity (fps) S (ft/ft) =0.0062 Tt = Travel time (min) V10 (fps) = V100 (fps) = Tt(10) (min) =1.8 Tt(100) (min) =1.5 D.Pipe Flow Assume flow velocity of 2 fps within storm drain pipes L (ft) =56 Legend: V (fps) =2 L = Pipe length (ft) Tt(10) (min) =0.5 V = Pipe flow velocity (fps) Tt(100) (min) =0.5 0.2 1.4 1.6 0.1 0.7 0.8 2132SRn KVu=V LTt60= 2132SRn KVu=V LTt60= 5 of 10 Job No.20153 Client Howell Job Name Hicks Lane Stormwater Detention Calculations Chkd PWR Date 04/24/23 By Dustin Behne Tc(10) (min) =,use minutes Tc(100) (min) =,use minutes 4. Rainfall Intensity (Butte County Std. 10.05-3.01) I10 = I100 = 5. Peak Design Flow Q10 (cfs) = Q100 (cfs) = Calculated Pre-Development Discharge Q10 (cfs) = Q100 (cfs) = Calculated Post-Development Discharge Q10 (cfs) = Q100 (cfs) = Increase in Flow Q10 (cfs) =Post-Developed Flow - Pre-Developed Flow Q100 (cfs) = Required basin storage from Haestad Methods PondPack software: 10 year =cu-ft 100 year =cu-ft 2.32 9.2 9 7.8 8 1,468 3.78 3.11 5.06 1.25 2.70 3.11 5.06 1.86 2.37 2,234 AICQ**= 6 of 10 Job No.20153 Client Howell Job Name Hicks Lane Stormwater Detention Calculations Chkd PWR Date 04/24/23 By Dustin Behne Allow Portion of Project Area to Bypass Detention System DB 2 (as shown on watershed map) bypass the detention system 1. Tributary Areas 1. Roof Surfaces (ac) =0.00 2. AC & hardscape (ac) =0.04 3. Gravel roads & parking (ac) =0.234. Landscape (ac) =0.46 Σ (ac) = 2. Runoff Coefficient (Butte County Std. D-5) 1. Roof Surfaces C-Factor =0.952. AC & hardscape C-Factor =0.90 3. Gravel roads & parking C-Factor =0.80 4. Natural Landscape C-Factor =0.43 Overall Composite C =0.57 3. Critical Storm Duration (storm resulting in largest detention volume, from Pond Pack software) A. Critical Storm =minutes 4. Rainfall Intensity (Butte County Std. 10.05-3.01) I10 = I100 = 5. Peak Design Flow Q10 (cfs) = Q100 (cfs) = 6. Allowable Discharge From Detention System (Pre-develop peak flow - flow bypassing detention peak flow) Q10 (cfs) = Q100 (cfs) = 0.72 40 1.01 1.54 0.42 0.63 0.83 2.06 AICQ**= 7 of 10 Job No.20153 Client Howell Job Name Hicks Lane Stormwater Detention Calculations Chkd PWR Date 04/18/2023 By Dustin Behne 8 of 10 Job No.20153 Client Howell Job Name Hicks Lane Stormwater Detention Calculations Chkd PWR Date 04/18/2023 By Dustin Behne 9 of 10 Job No.:20153 Sheet:Project:Hicks Lane A.P.N. 007-010-054 Calc.DJB Date:4/17/2023Subject:Discharge Orifice Analysis Chkd.PWR Date:4/18/2023 Pre-Developed Design Flows/Allowable Discharge: Q10 (cfs) =0.83 Q100 (cfs) =2.06 Detention Pipe Outfall Pipe Depth in pipe10 (in) =10.44 Depth in pipe10 (in) =3.72 Depth in pipe100 (in) =12.60 Depth in pipe100 (in) =4.56 10-Year Discharge: 10-year orifice (rectangular) Csharp edge =0.61 Outfall Type: Submerged Discharge h 1 (in) = 10.44 h 2 (in) = 3.72 h (in) = 6.72 g (ft/sec2) =32.20 H (in) = 2.00 use 2" L (in) =16.00 use 16" A (sf) =0.22 Q10 (cfs) =0.81 100-Year Discharge: 10-year orifice (rectangular) Csharp edge =0.61 Outfall Type: Submerged Discharge h 1 (in) = 12.60 h 2 (in) = 4.56 h (in) = 8.04 g (ft/sec2) =32.20 H (in) = 2.00 use 2" L (in) =16.00 use 16" A (sf) =0.22 Q100 (cfs) =0.89 100-year orifice (rectangular) Csharp edge =0.61 Outfall Type: Free Discharge h 1 (in) = 12.60 h 2 (in) = 10.44 h (in) = 0.97 g (ft/sec2) =32.2 H (in) = 2.38 use 2-3/8" L (in) =18.00 use 18" A (sf) =0.30 Q100 (cfs) =0.41 ΣQ (cfs) =1.30 Rectangular Orifice Detail Submerged Orifice Detail Free Discharge Orifice Detail ghCAQ2= ghCAQ2= 10 of 10 DRAFT OFROLLS ANDERSON & ROLLSRAR 1 1 5 YELLOWSTONE DRIVE CHICO, CALIFORNIA 9 5973-58 11 TELEPHONE 530-895-1422 CIVIL ENGINEERS APPROVED DATE DESIGNED DRAWN CHECKED DRAWING NO. JOB NO. PREPARED FOR : 1 20153 1 PWR CAD DJB HICKS LANE - A.P.N. 007-010-054 WATERSHED MAPGREG HOWELL APRIL, 2023 2 LEGEND DRAIN BASIN AREA TABLE DRAIN BASIN 1 2 ROOF AREA (AC) 0.039 0.000 AC/HARDSCAPE AREA (AC) 0.009 0.036 LANDSCAPE AREA (AC) 0.229 0.205 GRAVEL AREA (AC) 1.103 0.226 TOTAL AREA (AC) 1.379 0.467 1 2 NOTESHICKS LANEC.M.A. ACCESS ROAD Channel Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Monday, May 8 2023 10-YR POST-DEV PIPE FLOW (CULVERT) Circular Diameter (ft) = 1.00 Invert Elev (ft) = 83.20 Slope (%) = 0.35 N-Value = 0.013 Calculations Compute by: Known Q Known Q (cfs) = 0.83 Highlighted Depth (ft) = 0.44 Q (cfs) = 0.830 Area (sqft) = 0.34 Velocity (ft/s) = 2.48 Wetted Perim (ft) = 1.45 Crit Depth, Yc (ft) = 0.39 Top Width (ft) = 0.99 EGL (ft) = 0.54 0 1 2 3 Elev (ft)Depth (ft)Section 82.50 -0.70 83.00 -0.20 83.50 0.30 84.00 0.80 84.50 1.30 85.00 1.80 Reach (ft) Channel Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Monday, May 8 2023 100-YR POST-DEV PIPE FLOW (CULVERT) Circular Diameter (ft) = 1.00 Invert Elev (ft) = 83.20 Slope (%) = 0.35 N-Value = 0.013 Calculations Compute by: Known Q Known Q (cfs) = 2.06 Highlighted Depth (ft) = 0.80 Q (cfs) = 2.060 Area (sqft) = 0.67 Velocity (ft/s) = 3.06 Wetted Perim (ft) = 2.22 Crit Depth, Yc (ft) = 0.62 Top Width (ft) = 0.80 EGL (ft) = 0.95 0 1 2 3 Elev (ft)Depth (ft)Section 82.50 -0.70 83.00 -0.20 83.50 0.30 84.00 0.80 84.50 1.30 85.00 1.80 Reach (ft) Channel Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Monday, May 8 2023 10-YR POST-DEV CHANNEL FLOW (POND TO CULVERT) Trapezoidal Bottom Width (ft) = 2.00 Side Slopes (z:1) = 3.00, 3.00 Total Depth (ft) = 1.40 Invert Elev (ft) = 83.40 Slope (%) = 0.60 N-Value = 0.030 Calculations Compute by: Known Q Known Q (cfs) = 0.83 Highlighted Depth (ft) = 0.25 Q (cfs) = 0.830 Area (sqft) = 0.69 Velocity (ft/s) = 1.21 Wetted Perim (ft) = 3.58 Crit Depth, Yc (ft) = 0.17 Top Width (ft) = 3.50 EGL (ft) = 0.27 0 2 4 6 8 10 12 14 16 Elev (ft)Depth (ft)Section 82.50 -0.90 83.00 -0.40 83.50 0.10 84.00 0.60 84.50 1.10 85.00 1.60 Reach (ft) Channel Report Hydraflow Express Extension for Autodesk® Civil 3D® by Autodesk, Inc. Monday, May 8 2023 100-YR POST-DEV CHANNEL FLOW (POND TO CULVERT) Trapezoidal Bottom Width (ft) = 2.00 Side Slopes (z:1) = 3.00, 3.00 Total Depth (ft) = 1.40 Invert Elev (ft) = 83.40 Slope (%) = 0.60 N-Value = 0.030 Calculations Compute by: Known Q Known Q (cfs) = 2.06 Highlighted Depth (ft) = 0.40 Q (cfs) = 2.060 Area (sqft) = 1.28 Velocity (ft/s) = 1.61 Wetted Perim (ft) = 4.53 Crit Depth, Yc (ft) = 0.28 Top Width (ft) = 4.40 EGL (ft) = 0.44 0 2 4 6 8 10 12 14 16 Elev (ft)Depth (ft)Section 82.50 -0.90 83.00 -0.40 83.50 0.10 84.00 0.60 84.50 1.10 85.00 1.60 Reach (ft)