ST9401WA-CS 950328WIER & ASSOCIATES, INC.
ENGIN[EFIING
SURVEYING
LAND PLANNING
March 28, 1995
Mr. Kenneth Griffin, P.E.
City Engineer
Engineering Department
City of Coppell
255 Parkway Boulevard
Post Office Box 478
Coppell, TX 75019
214/462-0022
RE: W&A # - 94093, DENTON TAP ROAD;
Coppell, Texas
Dear:
In our meeting last Friday we reviewed the drainage patterns and possible
culvert construction options for proposed Denton Tap Road north of Denton Creek.
The improvement options were based on extending the proposed 3-6' x 5' culvert
preliminarily planned for construction by the Texas Department of Transportation. In
that meeting we indicated that extending the culvert along Denton Tap Road to Denton
Creek would involve the following:
There is limited horizontal space available between the existing roadway surface
and existing utilities on both sides of the roadway. A wide structure (20' out to
out for culvert) would be difficult to install while keeping traffic in service and
only one lane of the road would be open at the point of installation. A typical
storm drain pipe could more easily be installed and would not require closing
lanes.
The culvert would take up considerable space limiting opportunities for
installation of other utilities.
The culvert extension improvements would be extremely expensive due to the
construction difficulty, and large size caused by a high downstream tailwater.
We estimated the cost to be on the order of $600,000.
The outlet of the structure would be near or at the Denton Creek bridge crossing,
which would increase erosion potential at this critical location.
In our meeting, I reminded you that we were of the opinion that the water course
has been diverted by adjacent property owner reclamation activities. The diversion if
honored potentially transfers substantial drainage improvement costs to the city. In our