SW8010216_COMPLIANCE_20010314

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO. SW D IOC ((O
DOC TYPE I ❑ CURRENT PERMIT
❑ APPROVED PLANS
❑ HISTORICAL FILE
COMPLIANCE EVALUATION INSPECTION
DOC DATE
YYYYMMDD

DETENTION POND ANALYSIS
FILE NAME: S:IWQSIPOND1010216.WK1
PROJECT #: SW8 010216
PROJECT NAME: Clarendon Office Park
REVIEWER: Lewis
DATE: 14-Mar-2001
Receiving Stream: Woodward Branch Class: C Sw HQW Chlorides: n/a
Drainage Basin: Lumber Index No. 15-25-2-8
Site Area 2.97 acres
Drainage Area 101713 O;Isquare feet Area in Acre 2.34
IMPERVIOUS AREAS
Rational C
Building
4992.00 square feet
Parking
28000.00 square feet
Sidewalks
5340.00 square feet
Future
26560.00 square feet
square feet
square feet
TOTAL
�_..... ;:64892 Q0 square feet Rational Cc= 0.07
SURFACE AREA CALCULATION
% IMPERVIOUS 63.80%
Des. Depth 5
TSS: 90
SA/DA Ratio
4.57%
Req. SA
4644 sf
Prov. SA
477.2` sf
VOLUME CALCULATION * place a "1" in the box if Rational is Used
Rational ?"
Des. Storm
':' 1'`!001
inches
Rv=
0.62
Bottom
10
msl
Perm, Pool
15 00
msl
Design Pool
16.1
msl
Design SA
5828
sf
Req. Volume
5291
cf
Prov. Volume
! 5830
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 = 1.26 in2
Q5 Area = 0.50 in'
Orifice Area 0.99 in'
Q= 0.024 cfs
10847
2169.4
1996.00
18.4 6,
:..:.....................::I
Drawdown> „2 5.days
COMMENTS
Surface Area , Volume and Orifice are within Design Guidelines