SW8000727_COMPLIANCE_20000915

STORMWATER DIVISION'CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
SW 75tt�%a�—I
DOC TYPE
❑ CURRENT PERMIT
❑ APPROVED PLANS
❑ HISTORICAL FILE
COMPLIANCE EVALUATION INSPECTION
DOC DATE.
OQ�S
YYYYMMDD

DETENTION POND ANALYSIS
FILE NAME: S:IWQSIPOND1000727.WK1
PROJECT #: SW8 000727
PROJECT NAME: Automotive Services
REVIEWER: sav
DATE: 15-Sep-2000
Receiving Stream: Northeast Cape_Fe,ar Rider Class: C_SW Chlorides: n/a
Drainage Basin: Cape Fear Index No. 18-74-(61)
Site Area 1.61 acres
Drainage Area 70131 60�,square feet needs to be verified
Area in Acres 1.61 acres
IMPERVIOUS AREA Rational C-list beside
each item below in El to E20
On -Site Buildings 16963.00 square feet
On -Site Parking 37801.00 square feet
On -Site Sidewalks 2212.00 square feet
square feet
square feet
square feet
TOTAL (' ;'56976Q0 Cc= 0.04
% IMPERVIOUS 81.24% Des. Depth 6.5 TSS: 90
SURFACE AREA CALCULATION
Rational ?
If Rational is used put a
SA/DA
4.07%
"1" in box E26. If not, leave it blank.
Req. SA
2858
square feet
Prov. SA:.;,
-2986,
square feet
[From plan Contours]
VOLUME CALCULATION
Perm. Pool Volume= 9397
Req. Forebay Volume= 1879.4
Bottom
18.50
MSL
Provided Volume= 1829
Perm. Pool
25'0.0`.
MSL
Percent= 1:9%
Design Pool
26.50
MSL
Design SA
3933
square feet
Des. Storm T.00,
inches
Req. Volume
Prov. Volume
4565
51 9
cubic feet
cubic feet
Rv= 0.78117396
SA @ _
Elevation=
ORIFICE CA
No. of Orifices
LATION
Avg. Head =
Flow Q2, cfs 0.026
Flow Q5, cfs 0.011
0.73 ft
Area, in 0.93
Area, in 0.37
1: Diameter, in 1 00 Area = 0.785 inY
Q, cfs = 0,022 Drawdown
COMMENTS
Surface Area , Volume and Orifice are within Design Guidelines.