HomeMy WebLinkAboutDrainage Report Letter1 JONES&CARTE R,iNc.
• ENGINEERS•PLANNERS•SURVEYORS
March 7, 2011
City of College Station
1101 Texas Avenue
College Station, Texas 77840
1718 Briarcre6l Dr., Suite 160 TEL 979 7318000
Bryan, TX 77802-2776 FAX 979 846 2893
AUSTIN DALLAS
HOUSTON BRENHAM
SAN ANTONIO ROSENBERG
BRYAN/COLLEGE STATION THEWOODLANDS
Texas Board of Professional Engineers Registration No. F-439
Re: REVISED - College Staton Utilities Expansion — Drainage Report Letter
J&C Job No. COO 13-014
To Whom It May Concern:
Jones and Carter, Inc. (J&C) is submitting this letter as an alternative to a drainage report for the College
Station Utilities Expansion facility (CSE).
BACI{GROUND:
The CSE facility is being constructed on an existing concrete parking lot -located adjacent.to and east of
the College Station Utilities Service Center (CSSC) office building, The construction will consist of
removing the existing parking lot and replacing with a 3,000sf office building and subsequent parking
area. The proposed construction will be contained within the extents of the current concrete parking lot.
The proposed CSE facility includes an additional 1,500sf pavement expansion as shown in Exhibit A.
CALCULATIONS: _
The Rational Method was used to calculate the pre and post development 100-Year Storm event runoff
rates for the pavement expansion area. These calculations were based on the additional 1,500sf parking
lot expansion and not on the entire property.
Qloo Pre Development = 0.15 CFS
Q100 Post Development = 0.39 CFS
As a result of redeveloping an existing impervious site, and resultant minor increase in runoff rates due to
the 1,500sf pavement expansion, the proposed CSE facility and pavement will result in insignificant
increases of runoff release rates. Additional drainage study or structure modifications are not
recommended to be necessary.
Sincerely,
`teve E . Duncan, P.E., LEED0 AP
Vice President
Bryan/College Station Operations Manager
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....
/ STEVE E. DUNCAN /
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Smart Engineering. Smart SolutionSTM www.jonescarter.com
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