Loading...
HomeMy WebLinkAbout3437 E. Copper Point - Storm Drainage Calculations:IVIL, ItJIJOV,aTi01J�, Iol.t G Storm Drainage Calculations 3437 E. Copper Point Meridian, ID December 30, 2013 Civil Innovations, PLLC PO Box 170811 Boise, ID 83717-0811 Phone: (208) 914-0770 www.civil-innovations.com Introduction 3437 E. Copper Point is a 0.47 acre parcel on the South Side of E. Copper Point Drive within the Silverstone complex at the Southeast corner of Eagle and Overland Roads in Meridian. This project includes the construction of 25 paved parking spaces, curb, landscaping, and an on-site drainage system. Existing Storm Drain Conditions The existing street, E. Copper Point Drive is a public street whose drainage system is owned and operated by ACHD. None of the construction proposed with this project will have any effect on the existing drainage system. The lot itself is currently undeveloped with bare dirt and weeds that are mowed during the growing season. Proposed Storm Drain Design Stormwater runoff from this project will be retained on-site in a seepage bed. The seepage bed is sized to hold all runoff from the 100 -year storm event. Water quality treatment is achieved by installation of a sand & grease trap and ASTM C-33 filter sand under the drain rock. The sand & grease trap has been designed to limit the flow velocity through the structure to under 0.5 feet per second during the 100 -year storm event. 3437 E. Copper Point Storm Drain Calculations Drainage Area 1 = 0.18 AC C = 0.95 T/C = 10 1(100 Yr) = 3.11 Q(100 YR) = 0.53 CFS V(100 Yr) = 708 CF (I = 1.15) V(100 Yr) + 15% Sediment 814 CF 1000 Gallon S/G Trap Total Width = Baffle Spacing = 48 In. 12 In. Flow Velocity = 0.13 Ft/Sec. Seepage Bed Lenth = 32 Ft. Width = 8 Ft. Depth = 6.5 Ft. Void Ratio = 0.4 Infiltration Rate = 8 In./H r. 1 -Hr Infiltration = 170.7 C. F. Storage Volume Required = 643.5 C. F. Storage Volume Provided = 665.6 C. F. Time to Drain = 4.1 Hr. 3.50 3.00 2.50 2.Q0 1.50 100 0.50 0.00 10 min NOAAAt3as 2 Intensity Duration Frequency 15 min 30 min 1hour 2 hours 3 hours 6 hours 12 hours 24 hours Duration in minutes and hours 8202.2 ACHD Stormwater Design Template ACHD has developed standardized worksheets to help establish consistency in calculation methodologies and assist in the review of drainage calculations. These worksheets shall be submitted along with plans for all ACHD plan reviews. The worksheets are not intended to replace the Engineers calculation methods or relieve the Engineer of responsibility for the design calculations. The worksheets are available on the ACHD website under the Stormwater Section or from the Stormwater Section upon request. Adopted: Res. 966 (1/12/11) 8200-2 Boise Area Intensity Durarlon Frequency.. hdenCitd inch?s per hour Design Stone 2 5 10 25 50 100 To---- ---- ----- ----. ---- _. --------- 10 min 1 21 37 1.46 2.37 z'3 3,11 44�- 15 min 1,02 1.41 1.66 200 `r 2,62 30 min 0 71 0 98 1 15 1.39 1 nc 1 32 1 hour 0 4� 0 62 0 73 Q 86 ' 01 1.16 'I. 2 hours 0 2-.. '.. Q 36. 042 -_ Q OQ fl 58 -_. Q.66. 3 hours u 20 0 27 0 32 0 37 0 43 1148 6 hours 0 13 0.17 0 2U 021 0,27 0 30 12 hours 0-03 0,11 0.13 Q iu 9 16 019 24 hours 0 Qo 0,07 0.08 0 09 0 11 0.12 3.50 3.00 2.50 2.Q0 1.50 100 0.50 0.00 10 min NOAAAt3as 2 Intensity Duration Frequency 15 min 30 min 1hour 2 hours 3 hours 6 hours 12 hours 24 hours Duration in minutes and hours 8202.2 ACHD Stormwater Design Template ACHD has developed standardized worksheets to help establish consistency in calculation methodologies and assist in the review of drainage calculations. These worksheets shall be submitted along with plans for all ACHD plan reviews. The worksheets are not intended to replace the Engineers calculation methods or relieve the Engineer of responsibility for the design calculations. The worksheets are available on the ACHD website under the Stormwater Section or from the Stormwater Section upon request. Adopted: Res. 966 (1/12/11) 8200-2 I I ; I I II I II I I I I I I I I I I I I I I I I I I I I T= I= I L I\ I I\ I DRAINAGE AREA PLANS I \ Ha SCALE :1"=10'-0"HORIZONTAL N woa I HORIZONTAL SCALE IN HH LB�NNO`I>ca ca I I =�o r� _— �NORTH� a fl o oa 3r 13437 E. COPPER POINT DRIVE STORM DRAIN DATA Z *- r o U c • SEEPAGE BED NO.1 r o '---__ HOW 1W ALLONSANG ANGGPEASEIRAIUCAFFICASTES H GAKTEO LID AND 12°EAFFLE SPACING H m j F p Q j( C] W _ I �I PINI=P66O.1I PIIATED LID] ►J _ N C PIM 1=MG0 A IB°INV DTR-CAG6R0 p] y I Q . .8 . . STNL50LF 1B'ADS ILT2 (N DW°A TO SBMt � d 0] O 3 d _ 1 BB6 GA. n B' w, TSO D SEEPAGE 6ED -T G-DNa'I Dn Sl-G3W 3437 E. COPPER POINT DRIVE DRAINAGE AREA DATA V f 1 L� AREA = 0.18 AC y T= I= I L I\ I I\ I I \ Ha I \ \ woa I mz \ I I =�o � \ oa 3r 1 03 iiiiiiiI m I cc ca Z Q p CL a W CL O 10 W r M M IDESIGNED QY I NTH C.400