Oakbend Addn-CS 900802ND!
NATHAN D.
MAIER
CONSULTING ENGINEERS, INC.
August 2, 1990
Ms. Shohre Daneshmand
City of Coppell
255 Parkway Blvd.
Coppell, Texas 75019
Re:
Thweat Road Drainage Improvements
NDM No.: 89-9-10~
Dear Shohre:
The purpose of this letter is to assert that, based on my professional opinion, the storm sewer line we pro-
pose along Thweat Road is adequately sized to accommodate the ultimate runoff along the right-of-way.
I base this statement on two considerations.
First, the only area that contributes to this line is on the south side of Thweat. On the north side of the
street, the ground slopes to the north.
Secondly, of the areas south of Thweat that do drain into this line, only three tracts are included. One is
in the ON(bend Tract itself. Obviously, since Oakbend is now under construction, we can accurately pre-
dict its runoff characteristics. For the other two tracts, the Lacy Tract and the Cistercian Tract, I have
used the maximum runoff coefficient called for in the City of Coppell's subdivision ordinance. That is to
say that nothing could be built on these tracts under any land use that would require more conservative
design assumptions.
If you need any additional information, please let us know.
Sincerely,
NATHAN D. MAIER
CONSULTING ENGINEERS, iNC.
Mike Daniel, P.E.
CMD/rdp
Three NorthPark/8800 N. Central Expwy./Suite 300/Dallas, Texas 75231/(214) 739-4741