SW8001125_COMPLIANCE_20010216

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
SW
DOC TYPE
❑CURRENT PERMIT
❑ APPROVED PLANS
❑ HISTORICAL FILE
COMPLIANCE EVALUATION INSPECTION
DOC DATE
WYYMMDD i
I

DETENTION POND ANALYSIS
FILE NAME: S:1WQSIPOND1001125.WK1
PROJECT #: SW8 001125
PROJECT NAME: Pier 1 Imports
REVIEWER: Lewis
DATE: 16-Feb-2001
Receiving Stream: Newport River Class: SA Chlorides: 37 mgll
Drainage Basin: WHO Index No. 21-17
Site Area 1.86 acres
Drainage Area 727:16 OO square feet Area in Acre 1.67
IMPERVIOUS AREAS
Rational C
Builidng 15460.00 square feet 1.00
Parking 43720.00 square feet 1.00
SW 1660.00 square feet 1.00
square feet
square feet
square feet
TOTAL I 6084Q 001square feet Rational Cc= 0.87
SURFACE AREA CALCULATION
% IMPERVIOUS 83.67%
Des. Depth 5
TSS: 90
SA/DA Ratio 5.99%
Req. SA 4358 sf
Prov. SA 4887'jsf
VOLUME CALCULATION * place a "1" in the box if Rational is used
Rational ?*
1
Des. Storm
1 00'
inches
Rv=
0.80
Bottom
11
msl
Perm. Pool
16 00'jmsl
Design Pool
..
17.16
msl
Design SA
6041
sf
Req. Volume
4$66
cf
Prov. Volume
6338
cf
ORIFICE CALCULATION
Avg. Head =
Flow Q2, cfs
Flow Q5, cfs
No. of Orifices
Diameter or
Weir Dimensions
FOREBAY
Perm. Pool Volume=
Req. Forebay Volume=
Provided Volume=
Percent=
SA @ _
Elevation=
Q2 Area = 1.13 in
Q5 Area = 0.45 in
Orifice Area 0.79 in
Q= 0.020 cfs
Drawdown �:' 2.9jdays
COMMENTS
Surface Area , Volume and Orifice are within Design Guidelines.
12313
2462.6
2598.00