SW8040523_COMPLIANCE_20040608

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
SW��^7�j3
DOC TYPE
❑ CURRENT PERMIT
❑ APPROVED PLANS
❑ HISTORICAL FILE
COMPLIANCE EVALUATION INSPECTION
DOC DATE
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YYYYMMDD

I
WET DETENTION POND ANALYSIS
FILE NAME:
PROJECT #: SW8 040523.jun04
PROJECT NAME: Royal Oak Commercial Tract
S:1WQS\POND1040523.jun04.xIs
REVIEWER: L Munn
DATE: 08-Jun-04
Receiving Stream: Fall Swamp Class: C SW
Drainage Basin: Lumber Index No. LBR59 15-25-1-12-2-1
Site Area 23.59 acres
Drainage Area square feet Area in Acres 19.69
IMPERVIOUS AREAS
Rational C
building
72400.00 square feet
parking
621222.00 square feet
sidewalk
1553.00 square feet
square feet
square feet
square feet
TOTAL square feet Rational Cc= 0.04
SURFACE AREA CALCULATION
% IMPERVIOUS 81.06%
Des. Depth 7
TSS: 90
SA/DA Ratio 3.45%
Req. SA 29613 sf
Prov. SA sf
VOLUME CALCULATION * place a "'I " in the box if Rational is used
Rational ?*
Des. Storm inches
Rv= 0.780
Bottom 42 msl
Perm. Pool .4.90 msl
Design Pool 51 msl
Storage met @elev 50.60 msl
�l Req. Volume --Vcf
Vol. Prov. at DP cf
ORIFICE CALCULATION
Perm. Pool Volume=
Req. Forebay Volurne=
Provided Volume=
Percent=
Elevation
49.00
51.00
Area
32302.00
37147.00
150111
30022.2
33613.00
rAT4&vn.
69449.00 69449.00
Avg. Head =
0.94 ft
Q2 Area =
9.96
sq. inches
Flow Q2, cfs
0.322 cfs
05 Area =
3.98
sq. inches
Flow Q5, cfs;
0.129 cfs
Orifice Area
7.07
sq. inches
No. of Orifices
............
1=
Q=
0.229
cfs
Diameter, inches
H x W
in
X
in
Drawdown
1weir
days
Surface Area @DP =
37147 sq. ft.
Falling Head Drawdown =
4.8 days
COMMENTS
Surface Area , Volume and Orifice are within Design Guidelines.