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HomeMy WebLinkAboutCC - Storm Drainage Storm Drainage Master for Dr. Malan Lot 4 Blk 2 Swindell Subdivision Client: McCarter Moorhouse, LLC 4660 N. Penngrove Way Suite 100 Meridian, ID 83646 Maso,n & A'5150CIatC5 Inc. Professional Engineers, Land Surveyors and Planners 924 3rd St. So., Suite B, Nampa, ID 83651 Ph (208) 454-0256 Fax (208) 467-4130 Job No. JA0822 Date: February 22, 2022 Revision Date: April 29, 2022 9212 Jor Lf Mason Associates)�� JA0822SD.xlsx Cover 1 of 2 CALCULATION METHODOLOGY FLOW CALCULATIONS Flow for the basin areas are calculated using the Rational Method. The "C"coefficient used in the calculations is based on weighted values as shown. Conveyance facilities are designed for a 25-year return frequency storm and the worst case condition between 10 minutes and 1 hour. The worst case storm for flow is the 10-minute duration. HYDRAULIC GRADE CALCULATIONS These calculations employ the Manning Equation. The hydraulic grade is based on calculated flow. EQUATIONS USED IN CALCULATIONS RATIONAL METHOD Q=CiA where: Q = Runoff Rate, cfs C = Runoff Coefficient i = Storm Intensity, in./hr. A= Basin Area(s), acres MANNING EQUATION V=1.49R2/3S112/n where: V=Velocity, fps R = Hydraulic Radius,ft. S = Channel Slope, ft./ft. n = Manning Roughness Coefficient Mason�y Associatesj. JA0822SD.xlsx Cover 2 of 2 PEAK FLOW CALCULATIONS FOR SUB-BASINS POST-DEVELOPED RUNOFF COEFFICIENT (C) = 0.85 Area 1 weighted landscape/roof/asphalt 0.7 Area 2 weighted landscape/roof/asphalt LOT TRAVEL TIME = 2.3 min DROP INLET CAPACITIES: VERTICAL CURB = 4.26 cfs(depth at top of curb) ROLLED CURB = 3.15 cfs (depth at top of curb) Location AREA DATA CALCULATIONS SUB-BASIN SUB-BASIN CURB GUTTER AVERAGE GUTTER GUTTER TOTAL 50yr AREA AREA TYPE LENGTH GUTTER TIME CAPACITY TIME I Q # ac (V,R) ft SLOPE min cfs Tc in/hr cfs 1 0.55 R 100 2.50% 0.4 4.31 10.0 3.16 1.48 2 0.20 R 65 2.00% 0.3 3.86 10.0 3.16 0.44 Mason Associate-5 JA0822SD.xlsx Conveyance SAND AND GREASE TRAP CALCULATION BASIN: 1 SEDIMENT/GREASE TRAP SIZING S&G TRAP DETENTION TIME NUMBER OF TANKS 1 NUMBER OF TANKS 1 DISCHARGE(CFS) 1.48 DISCHARGE(CFS) 1.48 VELOCITY-MAXIMUM(FPS) 0.50 S&G STORAGE VOLUME(CF) 152.00 REQUIRED THROAT AREA(SF) 2.96 DETENTION TIME,T(SEC) 103 TANK SIZE (gal) 1,000 IS T>40 SEC.? YES TANK WIDTH (FT) 4.00 THROAT-WIDTH (in) 12 [VELOCITY-ACTUAL(fps) 0.37 BASIN: 2 SEDIMENT/GREASE TRAP SIZING S&G TRAP DETENTION TIME NUMBER OF TANKS 1 NUMBER OF TANKS 1 DISCHARGE(CFS) 0.44 DISCHARGE(CFS) 0.44 VELOCITY-MAXIMUM(FPS) 0.50 S&G STORAGE VOLUME(CF) 33.00 REQUIRED THROAT AREA(SF) 0.89 DETENTION TIME,T(SEC) 75 TANK SIZE(gal) DB-350 IS T>40 SEC.? YES TANK WIDTH (FT) 3.42 THROAT-WIDTH (in) 5 [VELOCITY-ACTUAL(fps) 0.31 Pipe Capacity- min. pipe slope req'd Area 1 & 2 Pipe Size, in., variable 12 0 0 Pipe Slope, %, variable 0.22% 0.22% 0.22% Mannings, n, variable PVC 0.009 0.009 0.009 Pipe Capacity, cfs 2.41 0.00 0.00 Mason & ASSOClatcsInc JA0822SD.xlsx Conveyance 1 RETENTION BASIN AREA NO.1 WORST CASE STORM VOLUME,100-yr BASIN AREA 0.55 acres RUNOFF COEFFICIENT(C) 0.85 weighted coefficient PERCOLATION RATE 1.50 in/hr PERCOLATION AREA 1040 sf SYSTEM VOID SPACE 1838 cf OFFSITE DISCHARGE 0 cfs PEAK MIN. 100 YR PEAK LESS FLOW VOIDS PERC POND DURATION DURATION INTENSITY* FLOW DISCH. VOLUME VOLUME VOLUME VOLUME (min) (hrs) (in/hr) (cfs) (cfs) (CO (d) (d) (CO 10 0.17 3.11 1.454 1.454 872 1,838 22 0 15 0.25 2.62 1.225 1.225 1,102 1,838 33 0 30 0.50 1.82 0.851 0.851 1,532 1,838 65 0 60 1.00 1.15 0.538 0.538 1,936 1,838 130 0 RETENTION DESIGN BASIN TOTAL STORAGE REQ'D= 1,935 cf WORST CASE STORM DURATION 60 minutes OFFSITE DISCHARGE 0.00 cfs SWALE VOLUME CALCULATION SWALE TOP AREA= 0 sf SWALE BOTTOM AREA= 0 sf SWALE AVE.END AREA= 0 sf SWALE DEPTH= 0 ft SWALE STORAGE= 0 cf SWALE INFILTRATION= 0 cf PIPE VOLUME CALCULATION PIPE AREA 24"DIA= 3.14 sf PIPE LENGTH= 105 sf PIPE BARRELS= 0.00 PIPE STORAGE= 0 Cf INFILTRATION BED CALCULATION W L INFILTRATION AREA= 1040 sf ROCK 9 43 ROCK BED DEPTH= 10 ft SAND 9 43 SAND BED DEPTH= 3 ft VOID SPACE IN SAND= 25% VOID SPACE IN DRAIN ROCK= 40% PERCOLATION RATE= 1 1.50 in/hr VOLUME IN VOIDS= 1838 cf PERCOLATION VOLUME= 130 cf INFILTRATION BED STORAGE= 1968 cf TOTAL STORED VOLUME= 1968 cf > 1935 cf THEREFORE STORAGE IS ADEQUATE TIME REQUIRED TO DISSIPATE VOLUME TIME= 1 hours Mason f3 Aesociafes�"rt JA0822SD.xlsx SD Area 1 1 of 1 RETENTION BASIN AREA NO.2 WORST CASE STORM VOLUME,100-yr BASIN AREA 0.20 acres RUNOFF COEFFICIENT(C) 0.70 weighted coefficient PERCOLATION RATE 1.50 in/hr PERCOLATION AREA 540 sf SYSTEM VOID SPACE 523 cf OFFSITE DISCHARGE 0 cfs PEAK MIN. 100 YR PEAK LESS FLOW VOIDS PERC POND DURATION DURATION INTENSITY* FLOW DISCH. VOLUME VOLUME VOLUME VOLUME (min) (hrs) (in/hr) (cfs) (cfs) (cq (eq (c0 (CO 10 0.17 3.11 0.435 0.435 261 523 11 0 15 0.25 2.62 0.367 0.367 330 523 17 0 30 0.50 1.82 0.255 0.255 459 523 34 0 60 1.00 1.15 0.161 0.161 580 523 68 0 RETENTION DESIGN BASIN TOTAL STORAGE REQ'D= 580 cf WORST CASE STORM DURATION 60 minutes OFFSITE DISCHARGE 0.00 cfs SWALE VOLUME CALCULATION SWALE TOP AREA= 0 sf SWALE BOTTOM AREA= 0 sf SWALE AVE.END AREA= 0 sf SWALE DEPTH= 0 ft SWALE STORAGE= 0 cf SWALE INFILTRATION= 0 cf PIPE VOLUME CALCULATION PIPE AREA 24"DIA= 3.14 sf PIPE LENGTH= 105 sf PIPE BARRELS= 0.00 PIPE STORAGE= 0 cf INFILTRATION BED CALCULATION W L INFILTRATION AREA= 540 sf ROCK 5 22 ROCK BED DEPTH= loft SAND 5 22 SAND BED DEPTH= 3 ft VOID SPACE IN SAND= 25% VOID SPACE IN DRAIN ROCK= 40% PERCOLATION RATE= I 1.50 in/hr VOLUME IN VOIDS= 523 cf PERCOLATION VOLUME= 68 cf INFILTRATION BED STORAGE= 590 cf TOTAL STORED VOLUME= 590 cf > 580 cf THEREFORE STORAGE IS ADEQUATE TIME REQUIRED TO DISSIPATE VOLUME TIME= 1 hours Mason f3, Associates/�t JA0822SD.xlsx SD Area 2 1 of 1 This Document, and the Concepts, Ideas and Design Incorporated herein are on instrument of professional services and are the Property of Mason and Associates, Inc., therefore they are not to be used in whole or part for any other project without the express Written Authorization of Mason and Associates, Inc.© All construction shall conform to the 2020 edition of the Idaho 0 Standards for Public Works Construction, most current edition of a City of Meridian Supplemental Specifications, and the Applicable Irrigation District Standards. y 0 IU 0 ra m O \ \ \ SNOISI/13t1 \ \ \\ \ \\ BUILDING N N N x N N N 01 \ \ \ \ "NIOSUR0 10 20- 40 ca W m o m 0 1p3 \ \ Scale: 1`20' rn w a \ \ SS Jpc a d \\ \\ \ \ \ LEGEND \ � \ \ \ � CALCULATED POINT � \\ \\ \\ \ ENCHMARK FOUND BRASS CAP MONUMENT a N �r \ q \ \ O FOUND 112"IRON PIN ® FOUND 5/8"IRON PIN \ \ \ \\ STORM DRAIN AREA #1 N N T SIGN r \ HARD SURFACE:15,695 SQ. FT. ® CATCH BASIN Q U ROOF AREA:6,112 SQ. FT. N LANDSCAPE AREA:2,095 SQ. FT. 2 ao� SAND & GREASE TRAP V) Y) AVERAGE SLOPE:2.5% 6 \ \ \ \\ LONGEST RUN:100' © POWER POLE ao WATER BLOW OFF f�, \ \ \\ \ sa © CABLE TV BOX \ \ \ \ DECIDUOUS TREE SPRINKLER BOX \ \ \ \ OO SANITARY SEWER MANHOLE L;77 \ \ so\ @ STORM DRAIN MANHOLE 6 \ \ \ LIGHT POLE \ / STORM DRAIN AREA #2 ® WATER VALVE 3 E \ \ HARD SURFACE:4,247 SQ. FT. � FIRE HYDRANT \ \ \ 9 ROOF AREA:2,313 SQ. FT. / GAS STUB \ \ \ N LANDSCAPE AREA:2,296 SQ. FT. - - �- o \ \ AVERAGE SLOPE:2.0% PROPERTY BOUNDARY LINE a C \ \ \ \ —---— SECTION LINE LONGEST RUN: F � 2 CENTER LINE --- w' u UTILITY, DRAINAGE AND IRRIGATION EASEMENT c'j PIPE N � \ \ \ x FENCE LINE o o z ii \ N SEWER LINE \ ---so--- STORM DRAIN LINE o \� q I OHP OVERHEAD POWER LINE O m \ I WS UNDERGROUND GAS LINE Z 2 W o W Lv \ \ N076'56'W 9.70' eo \ \ S8943'03 — 4 — ————————————— ——————— 'W OHP OHP P OH OHP \ � m \ I � \ \ E OVERLAND ROAD a N u. O ui Q U Q .- Q m 0 O Z NOT APPROVED FOR CONSTRUCTION p O Lu 2