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HomeMy WebLinkAbout5900 Comanche Dr Hydrology-Drainage Study 208 Oak Street Bakersfield, CA 93304-2433 Tel: 661.325.9474 - Fax 661.322.0129 www.cornerstoneeng.com CCiivviill EEnnggiinneeeerriinngg SSuurrvveeyyiinngg SSeerrvviicceess SSeewweerr && WWaatteerr EEnnggiinneeeerriinngg SSttoorrmm WWaatteerr EEnnggiinneeeerriinngg SSttoorrmm WWaatteerr QQuuaalliittyy SSWWPPPPPP RRooaadd AAnndd SSttrreeeett EEnnggiinneeeerriinngg SScchhooooll SSiittee EEnnggiinneeeerriinngg SSiittee DDeevveellooppmmeenntt,, PPllaannnniinngg AAnndd SSuurrvveeyyiinngg CCoonnssttrruuccttiioonn SSttaakkiinngg SSeerrvviicceess RReeddeevveellooppmmeenntt AArreeaa EEnnhhaanncceemmeenntt EEnnggiinneeeerriinngg TTrraaffffiicc EEnnggiinneeeerriinngg TTrraannssppoorrttaattiioonn PPllaannnniinngg C O N S U L T I N G C I V I L E N G I N E E R S & L A N D S U R V E Y O R S CORNERSTONE ENGINEERING September 25, 2017 Job No.: 428-08-00 City of Bakersfield Public Works Department Subdivisions Section RE: Hydrology/Drainage Report-5900 Comanche Drive Countryside Construction is proposing a commercial development at the southwest corner of Comanche Drive and Highway 178. Storm water from the project site and Comanche Drive will be collected on site and retained in a terminal basin. Storm water on Highway 178 will be handled by Caltrans Collection facilities. This report covers Phase A of the project and includes the analysis of a temporary on-site retention basin. Drainage from Jade Hill Drive will not drain on-site. Drainage from Comanche Drive will drain on-site. The attached drainage study includes Inlet and Pipe Hydrology calculations for the project at full build out to ensure that the drainage will meet city standards after all phases are constructed. Calculations specifically for Phase A have been supplied to show that the hydrology works for Phase A alone as well. Inlet Hydrology calculation for inlet 2, which will take on additional storm water during Phase A, has been provided as well to ensure the inlet capacity is adequate for all phasing situations. Separate Retention Basin Calculations have been provided for full project build out and for Phase A only. The Final Retention Basin location is not known at this time, thus it cannot be shown. The Temporary Retention Basin calculations and design are included herein. The temporary basin will only serve Phase A of the project. The lowest inlet within Phase A is 780.26’. The temporary basin’s high water line elevation is at 779.26’ to allow for 1 foot of freeboard. The elevation at the bottom of the basin is 771.26’; the maximum water depth is 8 feet. The temporary basin will provide a volume of 29,943 cubic feet, or approximately 0.69 acre-feet. Per City of Bakersfield Subdivision and Engineering Design Policy Manual (1989), the required volume for the temporary basin serving Phase A is 29,340 cubic feet, or approximately 0.67 acre-feet. See attached calculations. We do not believe that the existing soil will allow for the basin to drain in 7 days. The soil is too dense and contains too much fines. We do not want to put sand in the bottom of the proposed basin, because it is temporary. In the future, a building will be constructed on the temporary basin location and deep sand is not a suitable foundation material. Currently, the site drainage goes to a drainage ditch located to the west of the site (shown on grading plans). The drainage ditch is located on city-owned property. We propose to put a small basin pump in the temporary basin that will drain the basin in approximately 3-5 days. It will discharge the storm water into the drainage ditch. Pump details are included within the grading plan. 208 Oak Street Bakersfield, CA 93304-2433 Tel: 661.325.9474 - Fax 661.322.0129 www.cornerstoneeng.com CCiivviill EEnnggiinneeeerriinngg SSuurrvveeyyiinngg SSeerrvviicceess SSeewweerr && WWaatteerr EEnnggiinneeeerriinngg SSttoorrmm WWaatteerr EEnnggiinneeeerriinngg SSttoorrmm WWaatteerr QQuuaalliittyy SSWWPPPPPP RRooaadd AAnndd SSttrreeeett EEnnggiinneeeerriinngg SScchhooooll SSiittee EEnnggiinneeeerriinngg SSiittee DDeevveellooppmmeenntt,, PPllaannnniinngg AAnndd SSuurrvveeyyiinngg CCoonnssttrruuccttiioonn SSttaakkiinngg SSeerrvviicceess RReeddeevveellooppmmeenntt AArreeaa EEnnhhaanncceemmeenntt EEnnggiinneeeerriinngg There will be two pumps. The second pump will be used in the case that the initial pump malfunctions. The Goulds Model 1DV, ½ Horsepower, 230 Volts, 1-phase pump has been specified. This pump is a vortex submersible sewage pump that has a solids handling capability of 1 3/8” diameter. The pump will be manually turned on the day after the storm event. A mercury switch will automatically turn the pump off when there is approximately 1-foot of water remaining in the basin. This will allow the basin to also act as a sedimentation basin. Fines will be retained in the basin to mitigate storm water pollution. With a head of approximately 7-feet, the pump will discharge approximately 0.14 CFS. The pre- development discharge rate, Q10, 6.2 cfs (see the Pre-Development Calculation attached). Therefore, the post-development discharge to the drainage ditch is less than the pre- development discharge rate. At 0.14 cfs and with a design retention basin volume of 30,280 cubic feet, the basin will be drained by the pump in approximately 2.5 days. The retention basin is also compliant as a NPDES post-development BMP. The retention basin is being used to mitigate the hydromodification and storm water pollution. The post-development discharge to the drainage ditch is much less than the pre-development discharge rate. The design of the pump is such that there will be 1-foot of storm water left in the basin. This allows the retention basin to also act as a sedimentation basin. This will ensure that the post- development water will have less sedimentation than the pre-development runoff. If both sump pumps fail in a major storm event, the storm water in the retention basin will backup into the lowest drainage inlet, drainage inlet #3, because the maximum water elevation is 1-foot below the flowline elevation of drainage inlet #3. If a large amount of water pools on top of drainage inlet #3, the water will eventually overflow into the adjoining neighbor to the west’s property (see Exhibit E). Attached are: Temporary basin for Phase A runoff volume calculations, Provided Temporary basin for Phase A design information, runoff volume calculations for the entire site at full project build out, Inlet Hydrology calculations, Pipe Hydrology calculations, Exhibit B, Exhibit C, Exhibit D, Exhibit E, Pre-Development Hydrology Calculation, Inlet Reports for each drainage inlet, and the pump’s technical brochure. If you have any questions, please contact Melissa Snyder by phone at (661)325-9474 ext. 208 or by email at mas@cornerstoneeng.com. Sincerely, CORNERSTONE ENGINEERING, INC. Derrill G. Whitten, Jr., PE, PLS, President RCE 51930 LS 7816 0' GRAPHIC SCALE ( IN FEET ) 60'60'30'30' 1 inch = 60 ft. JA D E H I L L S D R (D R A I N S O F F - S I T E ) COMANCHE DR R O U T E 1 7 8 ( C A L T R A N S D R A I N A G E - D O E S N O T D R A I N O N - S I T E ) 0' GRAPHIC SCALE ( IN FEET ) 20'20'10'10' 1 inch = 20 ft. 0' JA D E H I L L S D R (D R A I N S O F F - S I T E ) 0' GRAPHIC SCALE ( IN FEET ) 20'20'10'10' 1 inch = 20 ft. 0' Da t e : 9/ 1 9 / 2 0 1 7 St u d y N a m e : SP R # 1 7 - 0 0 4 1 Ca l c u l a t e d b y : MA R Ch e c k e d b y : DG W St o r m R e t u r n : 10 y r Po i n t s Ru n o f f T( t ) Tc Sl o p e I Q Fl o w P a t h V e l o c i t y N o t e s : Su b a r e a T o t a l C o e f f . " C " To t a l L e n g t h Su b t o t a l To t a l Min u t e s M i n u t e s ft / f t in / h r cf s ft ft / s e c 0 10 . 0 7. 7 0 7. 7 0 0. 4 5 3. 4 6 5 3. 4 6 5 10 . 0 1. 8 0 6. 2 UN D E V E L O P E D - T Y P E D S O I L DI T C H Ar e a ( a c r e s ) " A r e a " x " C " Ci t y o f B a k e r s f i e l d H y d r o l o g y M a n u a l In l e t H y d r o l o g y PR E - D E V E L O P M E N T Da t e : 9/ 1 9 / 2 0 1 7 St u d y N a m e : SP R # 1 7 - 0 0 4 1 Ca l c u l a t e d b y : MA R Ch e c k e d b y : DG W St o r m R e t u r n : 10 y r Po i n t s Ru n o f f T( t ) Tc Sl o p e I Q Fl o w P a t h V e l o c i t y N o t e s : Su b a r e a T o t a l C o e f f . " C " To t a l L e n g t h Su b t o t a l To t a l Min u t e s M i n u t e s ft / f t in / h r cf s ft ft / s e c 0 10 . 0 0. 3 5 0. 3 5 0. 9 5 0. 3 3 2 5 0. 3 3 2 5 10 . 0 1. 8 0 0. 6 DI 1 D e p t h = 4 . 3 4 " a t g u t t e r DI 1 0 10 . 0 2. 3 0 2. 3 0 0. 9 0 2. 0 7 2. 0 7 0 10 . 0 1. 8 0 3. 7 DI 2 D e p t h = 4 . 2 6 " a t g u t t e r DI 2 0 10 . 0 0. 4 9 0. 4 9 0. 9 0 0. 4 4 1 0. 4 4 1 10 . 0 1. 8 0 0. 8 DI 3 D e p t h = 2 . 5 0 " a t g u t t e r DI 3 0 10 . 0 1. 3 0 1. 3 0 0. 9 0 1. 1 7 1. 1 7 10 . 0 1. 8 0 2. 1 DI 5 D e p t h = 3 . 8 6 " a t g u t t e r DI 5 0 10 . 0 1. 4 3 1. 4 3 0. 9 0 1. 2 8 7 1. 2 8 7 10 . 0 1. 8 0 2. 3 DI 6 D e p t h = 4 . 0 4 " a t g u t t e r DI 6 PH A S E A 0 10 . 0 1. 5 1 1. 5 1 0. 9 0 1. 3 5 9 10 . 0 1. 8 0 2. 4 DI 3 D e p t h = 7 . 1 3 " a t I N L E T F O R P H A S E A DI 3 Tr i b u t a r y A r e a t o D I 3 f o r P h a s e A i s la r g e r t h a n a t F u l l B u i l d - O u t (S e e E x h i b i t s B & C ) In l e t H y d r o l o g y Ci t y o f B a k e r s f i e l d H y d r o l o g y M a n u a l Ar e a ( a c r e s ) " A r e a " x " C " FU L L B U I L D O U T Inlet Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc.Tuesday, Aug 8 2017 <Name> Curb Inlet Location = Sag Curb Length (ft) = 4.00 Throat Height (in) = 6.00 Grate Area (sqft) = -0- Grate Width (ft) = -0- Grate Length (ft) = -0- Gutter Slope, Sw (ft/ft) = 0.083 Slope, Sx (ft/ft) = 0.010 Local Depr (in) = 2.00 Gutter Width (ft) = 2.00 Gutter Slope (%) = -0- Gutter n-value = 0.013 Calculations Compute by: Known Q Q (cfs) = 3.70 Highlighted Q Total (cfs) = 3.70 Q Capt (cfs) = 3.70 Q Bypass (cfs) = -0- Depth at Inlet (in) = 6.26 Efficiency (%) = 100 Gutter Spread (ft) = 20.90 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc.Tuesday, Aug 8 2017 <Name> Grate Inlet Location = Sag Curb Length (ft) = -0- Throat Height (in) = -0- Grate Area (sqft) = 4.00 Grate Width (ft) = 2.00 Grate Length (ft) = 2.00 Gutter Slope, Sw (ft/ft) = 0.083 Slope, Sx (ft/ft) = 0.020 Local Depr (in) = 3.00 Gutter Width (ft) = 2.00 Gutter Slope (%) = 1.33 Gutter n-value = 0.013 Calculations Compute by: Known Q Q (cfs) = 0.80 Highlighted Q Total (cfs) = 0.80 Q Capt (cfs) = 0.80 Q Bypass (cfs) = -0- Depth at Inlet (in) = 5.50 Efficiency (%) = 100 Gutter Spread (ft) = 4.12 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc.Tuesday, Sep 19 2017 <Name> Grate Inlet Location = Sag Curb Length (ft) = -0- Throat Height (in) = -0- Grate Area (sqft) = 4.00 Grate Width (ft) = 2.00 Grate Length (ft) = 2.00 Gutter Slope, Sw (ft/ft) = 0.083 Slope, Sx (ft/ft) = 0.020 Local Depr (in) = 3.00 Gutter Width (ft) = 2.00 Gutter Slope (%) = 1.33 Gutter n-value = 0.013 Calculations Compute by: Known Q Q (cfs) = 2.40 Highlighted Q Total (cfs) = 2.40 Q Capt (cfs) = 2.40 Q Bypass (cfs) = -0- Depth at Inlet (in) = 7.13 Efficiency (%) = 100 Gutter Spread (ft) = 10.89 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc.Tuesday, Aug 8 2017 <Name> Grate Inlet Location = Sag Curb Length (ft) = -0- Throat Height (in) = -0- Grate Area (sqft) = 4.00 Grate Width (ft) = 2.00 Grate Length (ft) = 2.00 Gutter Slope, Sw (ft/ft) = 0.083 Slope, Sx (ft/ft) = 0.028 Local Depr (in) = 3.00 Gutter Width (ft) = 2.00 Gutter Slope (%) = 0.20 Gutter n-value = 0.013 Calculations Compute by: Known Q Q (cfs) = 2.10 Highlighted Q Total (cfs) = 2.10 Q Capt (cfs) = 2.10 Q Bypass (cfs) = -0- Depth at Inlet (in) = 6.86 Efficiency (%) = 100 Gutter Spread (ft) = 7.56 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- Inlet Report Hydraflow Express Extension for Autodesk® AutoCAD® Civil 3D® by Autodesk, Inc.Tuesday, Aug 8 2017 <Name> Grate Inlet Location = Sag Curb Length (ft) = -0- Throat Height (in) = -0- Grate Area (sqft) = 4.00 Grate Width (ft) = 2.00 Grate Length (ft) = 2.00 Gutter Slope, Sw (ft/ft) = 0.083 Slope, Sx (ft/ft) = 0.035 Local Depr (in) = 3.00 Gutter Width (ft) = 2.00 Gutter Slope (%) = 0.20 Gutter n-value = 0.013 Calculations Compute by: Known Q Q (cfs) = 2.30 Highlighted Q Total (cfs) = 2.30 Q Capt (cfs) = 2.30 Q Bypass (cfs) = -0- Depth at Inlet (in) = 7.04 Efficiency (%) = 100 Gutter Spread (ft) = 6.87 Gutter Vel (ft/s) = -0- Bypass Spread (ft) = -0- Bypass Depth (in) = -0- FEATURES Casing: Corrosion resistant AISI 304 SS designed for long lasting performance. Impeller: AISI type 304 stainless steel construction; vortex design. Mechanical Seal: Drive lube silicon carbide sealing faces; all metal components of AISI type 300 stainless steel running in protected oil chamber. Elastomers: BUNA-N Pump Support Feet: Motor Shell and Lifting Handle: Constructed of AISI type 304 series stainless steel. Shaft: AISI type 304 stainless steel high strength pump shaft with keyed and locking cap screw impeller fastening. Discharge: 1½" and 2" NPT for horizontal connection to rigid, flexible or guide rail piping connection. NOTE: See accessory section guide rail systems, type A10-20 for simplex or duplex system or base elbow rail systems. Model 1DV/2DV 1½" AND 2" SUBMERSIBLE SEWAGE PUMP TECHNICAL BROCHURE B1DV/2DV PAGE 2 Wastewater Goulds Water Technology APPLICATIONS Vortex submersible sewage pumps for simplex and duplex installations in small lift stations, drainage systems or raw water applications requiring solids handling capability of 13⁄8" and 2" diameter made specifically for: • Homes and farms • Mobile home parks and motels • Schools and hospitals • Municipal package systems • Industrial treatment systems • Dewatering applications SPECIFICATIONS Pump: • 11⁄2" discharge on 1⁄2 HP • 2" discharge on 3⁄4 HP and larger • Solid size: 13⁄8" solids on 1⁄2 HP; 2" solids on 3⁄4 HP and larger • Capacities: to 130 U.S. GPM (41 m3/h) • Total heads: to 39 feet TDH (14 m) • Temperature: 104ºF (40ºC) continuous 140ºF (60ºC) intermitten • Maximum submergence: to 17 feet (5 m) • AISI 304 SS casing • AISI 304 SS impeller • Continuous duty rated, non-overloading motor Motor: • Single phase: 60 Hz, 3450 RPM, 1⁄2 HP, 115 V; 1⁄2 to 1 HP, 230 V. • Three phase: 60 Hz, 3450 RPM, 1⁄2 to 11⁄2 HP, 230 and 460 V. • Non-overloading. • Air-filled, class F insulated motor. • Thermal overload protection: built-in with automatic reset on single phase, 115 V and 230 V models. • Three phase models require external overload in panel. • Power cord: 20 feet long. • Single phase 115 V and 230 V models are supplied with molded NEMA plugs and built-in capacitors. • Three phase models are supplied with bare leads. • Float controls: optional, see accessory section for simplex or duplex system requirements. • Rotation is clockwise when viewed from top. Component Material Pump body and motor casing Stainless steel (AISI 304) Impeller Stainless steel (AISI 304) Lower mechanical seal Silicon carbide/silicon carbide Upper lip seal Nitrile rubber Motor Shaft Stainless steel (AISI 304) Handle Nylon PAGE 3 Wastewater Goulds Water Technology 0 1250 20 40 CAPACITY TO T AL D YN A M I C H E A D FEET U.S. GPM 30 10 5 15 25 35 10050 1500 2 10 4 6 8 METERS 0 10 2015 30 m3/hr 12 25 75 255 1DV51C-V1⁄2 HP 2DV51D-V 3⁄4 HP 2DV51E-V1 HP 2DV51F-V11⁄2 HP MODEL INFORMATION Order Maximum Start Capacitor Resistance Cord Discharge Weight Number HP Volts Phase Amps Amps uF/V Start/ RPM Length Connection Solids (lbs.) Line-Line 1DV51C0VA 115 1 9.8 51.0 70/250 1.6 / 0.6 22 1DV51C1VA ½ 230 4.2 26.3 20/450 5.9 / 2.6 1½" 13⁄8" 1DV51C3VA 3 2.3 14.6 NA NA / 11.7 20 1DV51C4VA 460 1.2 7.5 NA NA / 14.7 2DV51D1VA 230 1 5.4 27.2 22/450 4.4 / 1.9 30 2DV51D3VA ¾ 3 3.4 24.9 NA NA / 6.0 3450 20' 25 2DV51D4VA 460 1.7 12.7 NA NA / 7.8 2DV51E1VA 230 1 7.0 30.6 30/450 4.2 / 1.9 2" 2" 34 2DV51E3VA 1 3 4.4 29.8 NA NA / 5.3 30 2DV51E4VA 460 2.2 15.2 NA NA / 6.6 2DV51F3VA 1½ 230 3 5.6 39.2 NA NA / 3.7 32 2DV51F4VA 460 2.8 19.9 NA NA / 4.8 H H1 L DISCHARGE SIZE 61⁄2" (165 mm) Dimensions Discharge Wt. Series HP Phase in inches (mm) Size (lbs.) H H1 L 1DV 1⁄2 3 153⁄8 (391) 31⁄2 (88) 71⁄2 (193) 11⁄2" 20 1 22 3⁄4 3 17¼ (438) 25 1 18 (458) 30 2DV 1 3 43⁄8 (111.5) 73⁄4 (198) 2" 30 1 1813⁄16 (478) 34 11⁄2 3 32 DIMENSIONS Goulds is a registered trademark of Goulds Pumps, Inc. and is used under license. © 2012 Xylem Inc. B1DV/2DV R1 April 2012 Xylem, Inc. 2881 East Bayard Street Ext., Suite A Seneca Falls, NY 13148 Phone: (866) 325-4210 Fax: (888) 322-5877 www.xyleminc.com/brands/gouldswatertechnology