DR9101-CS 900719July 19, 1990
I ,azo, Starek & Tang, Inc.
Engineers · Planners
Ms. Shohre Daneshmand, P.E.
City of Coppell
Post office Box 478
Coppell, Texas 75019
Re: Oak Trail Drainage
Dear Ms. Daneshmand:
As requested, we have reviewed the design of the
proposed Oak Trail storm sewer as follows:
Item 1.
To determine the severity of the sanitary
sewer conflict by comparing field eleva-
tions of manholes with plan elevations.
Item 2.
To develop costs of a storm sewer system
to accommodate future flows if local
streets are improved.
Our conclusions regarding these items are as follows:
Item 1.
A comparison of field and plan elevations
for the existing sanitary sewer manholes
indicates differences which vary from
0.5 feet to almost 3 feet. It appears now
that the profile of the existing storm
sewer plans may be adjusted to eliminate a
conflict between the existing sanitary
sewer and proposed storm sewer without
additional measures that we previously
discussed.
Item 2.
The enclosed exhibit shows the size of
storm sewer lines which we would recommend
to accommodate future flows if the local
streets are improved. The system is
estimated to cost $20,300 more than the
existing design.
330 Union Station
Dallas, Texas 75202-4802
214/748.6740
Ms. Shohre Daneshmand,
July 19, 1990
Page 2
P,Eo
We also reviewed the size of the proposed storm sewer
lines in the existing design, should the design
discussed in Paragraph 2 above not be adopted. We
recommend that the 33-inch line be increased to
36 inches from Station 0+00 to Station 5+00 as shown in
the Oak Trail Drainage Study for Option 2. This is
estimated to cost approximately $4500 more than the
existing design.
We are available to discuss these options at your
convenience.
Sincerely,
n Hltt, P.E.
Vice President
GH/smh
OAK TRAIl.
PROPOSED
DRAINA6E
IMPROVEMENTS
"~ I VICINITY MAP ~