685 Sailfish Dr POOL22-0026 calcs_ss(Aug updated)1Comp. By:
Date:
Public Works Department
City of Atlantic Beach
Permit No:
Address:685 Sailfish Drive E
Required Storage Volume
Criteria:
Section 24-66 of the City of Atlantic Beach's Zoning, Subdivsion, and Land Development Regulations requires
that stormwater runoff from impervious areas be stored onsite. Volume to be retained is as follows:
V = CAR/12 which is the Modified Rational Method for estimating stormwater runoff
Where:V = Volume of Runoff to be stored (cubic feet)
C = Runoff Coefficient, 0.92, the difference between impervious area (C=1.0)
and undeveloped conditions (C=0.08).
A = Impervious Area (square feet)
R= 25-yr / 24-hr rainfall depth (9.3 inches for Atlantic Beach)
Onsite Storage Volume Required for Impervious Area:
Lot Area = 8,131 ft2
Impervious Area (A) = 3,370 ft2 =41.4%
V = 0.92 x 3,370.0 x 9.3 /12
V = 2,403 ft3
Provided Storage:
Area 1 - FRONT Area Storage Sideslope:4 :1
(ft)(ft2) (ft
3)
12.8 243 BOTTOM size:X
13.3 711 TOB size:X
Area 2 - BACK Area Storage
(ft)(ft2) (ft
3)
12.8 633 BOTTOM size:X
13.3 1,078 TOB size:X
Area 3 -Area Storage
(ft)(ft2) (ft3)
BOTTOM size:0 X 0
TOB size:0 X 0
Inground Storage: = A*d/pf
Total Storage Area at TOB (A) =1789.0 ft2
Depth to ESHWT from BOTTOM (d) =2.5 ft, default is 2.0 ft, verify onsite ESHWT
Pore Factor (pf) = 0.4 default is 0.4
Inground Storage Provided =1789.0 ft3
Required Treatment Volume =2,403 ft3
Supplied Treatment Volume =2,455 ft3
239
428
0
8/16/2022
Retention 685 sailfish drive calcs 8/16/2022
Reynold D.
Peterson
Digitally signed by
Reynold D. Peterson
Date: 2022.08.16
09:37:55 -04'00'
By Toni Gindlesperger at 9:30 am, Sep 12, 2022