HomeMy WebLinkAboutdrainage report letterBrewers -��; Escalante
CONSULTING ENGINEERS
July 16, 2010
City of College Station
Planning & Development Services
1101 Texas Avenue
College Station, Texas 77840
RE: CHASE BANK — TOWER POINT
Site Plan Review Submittal - Drainage Report Letter
To Whom It May Concern:,
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This letter is to certify that the drainage design for the proposed Chase Bank — Tower Point project was
completed in accordance to the design assumptions included in the report entitled Stormwater Draiange
Report for Tower Point Infrastructure Development College Station, Texas. This report was prepared for
Weiner Development Corporation by Walter P. Moore & Associated, Inc., dated October 7, 2009 and
amended December 11, 2009.
Similar to the above - mentioned drainage report, the drainage design for the Chase Bank system assumed
the following:
1. Runoff rates were calculated utilizing a conservative 0.90 runoff coefficient for the entire
Chase Bank lot.
2. The minimum time of concentration value was taken to be 10 minutes.
3. The drainage system was designed to handle the I 0 -year storm event utilizing the following
equation: i= 80/(Tc +8.5) ^0.763
Using these assumptions the designed peak flow (in cfs) generated from the Chase Bank development is
6.99 cfs. In conformance with the overall drainage report for the Tower Point development, the Chase
Bank drainage system directs its generated storm water to the an inlet located at the north end of the Lot 14
which is designated as `Structure 9'. According to this same report `Structure 9' has an available capacity
of 12.74 cfs which is far above what the Chase Bank lot will generate.
To summarize, the Chase Bank drainage system is design using identical design assumptions and storm
events as the overall Tower Point Development drainage system, to which the Chase Bank system outfalls
into. Furthermore Chase Bank, as directed by the Tower Point Development storm water report, will direct
its storm water to `Structure 9' and will not exceed its available capacity.
Respectfully,
P.
Craig R. Artze, P.E.
Brewer & Escalante
7600 West Tidwell, Suite 103
Houston, Texas 77040
Texas Registered Engineering Firm #2136
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CRAIG R. ARTZE
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