1852 SEA OATS RES23-0076 _Public Works DepartmentComp. By: Mathieu Builders
Date: 4/4/2023
Public Works Department
City of Atlantic Beach
Permit No:
Address: 1852 Sea Oats Drive
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 = CARl12 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 124 -hr rainfall depth (9.3 inches for Atlantic Beach)
Onsite Storage Volume Required for Impervious Area:
Lot Area = 10647 ft2
Impervious Area (A) = 3880 ft2 — 36%
V = 0.92 x 3880 x 9.3 1
V = 2767 ft3
Provided Storage:
Area 1 - FRONT
Area
Storage
Sideslope:
4 :1
(ft)
(ft)
(ft)
55
BOTTOM
size:
X
268
TOB
size:
X
Area 2 - BACK
Area
Storage
(ft)
(ft)
(ft)
9
1169
718
BOTTOM
size:
X
9.5
1708
TOB
size:
X
Area 3 - Relative Elev.
Area
Storage
(ft)
(ft2)
(ft)
0.0
0
BOTTOM
size:
0 X
0
0.0
0
TOB
size:
0 X
Inground Storage: = A'dlpf
Total Storage Area at TOB (A) = 1708 ft2
Depth to ESHWT from BOTTOM (d) = 4 ft, default is 2.0 ft, verify onsite ESHWT
Pore Factor (pf) = 0.4 default is 0.4
Inground Storage Provided = 2732.8 ft'
Required Treatment Volume = 2767 ft,
Supplied Treatment Volume = 3450.8 ft'
12
0
0