HomeMy WebLinkAboutDraiange Letter 2September 25, 2006
Josh Norto~ E.l.T.
Graduate Engineer
EMAIL: r m en gin ccr @j un o .com
City of College Station
1101 Texas Avenue South
College Statio~ TX 77842
RE: Drainage Letter for Westerheim Custom Homes
240 Southwest Parkway, College Station, TX
Lot SA, Block D -Ashford Square Subdivision, Brazos County
RME No. 201-0289
Dear Josh,
The proposed addition referenced above consists of a 2,378 square-foot office building, parking,
and associated sidewalks. Some parking and drives to support this facility are currently in place.
Using the Rational Method and the following parameters, an increase in runoff of approximately
0.42 cfs during the 100-year rainfall event would be experienced.
Ration Method: Q =CIA
CEXIsT = 0.30 CNEw = 0.95
I= 11.63 in/hr Tc= 10 min.
A(affected) = 0.055 acres
This runoff is a negligible amount and therefore should not create any adverse impacts to
downstream drainage structures and/or facilities.
Sincerely,
CDl-201-0289-LOl Page-I ofl