ST9304-CS 970306 DALLAS COUNTY
PUBLIC WORKS
March 6, 1997
Mr. Thomas J. Knicker, P.E.
Halif'Associates, Inc.
8616 Northwest Plaza Drive
Dallas, Texas 75225
Re: Belt Line Road -- Project No. 490-403.1/91-829
(Denton Tap Road to MacArthur Boulevard)
Drainage Review
Dear Mr. Knieker:
Attached are the preliminary plans submitted for review. The City of Dallas has not yet submitted
their review comments. Please address all the comments on the plans and in this letter. Re-submittals
to the County should include the original marked set of plans and should address the comments on
the plans and in this letter. Please call me at 214-653-7151 if you have any questions concerning the
project.
Sincerely,
E
Project Engineer ,-
~achments
xc: Ken Griffin, P.E., Assistant City Manager/City Engineer, City of Coppell
David Dybala, P.E., Director of public Works, City of Dallas
8'29/DRAn, iREV. LTR
411 Elm Street Dallas, Texas 75202 653-7151
COMMENTS
1. Add a note to both the first page of the paving plans and to the general notes in the contract
specifications that the contractor must replace any existing brick paver driveway bands
disturbed during construction.
2. Label all rights-of-way and easements.
3. The City of Coppell will be designing street lights, traffic signals and irrigation conduits for
incorporation the final construction and bid package. Please provide a base CAD drawing
to the County for Coppell's design.
4. TU Electric is processing a proposed railroad spur replacement agreement with the City of
Dallas and the County. If the agreement is passed, the County will pave through the current
railroad crossing but follow the currently designed cross-slope transitions to accommodate
a future spur crossing.
5. The City had previously requested brick paver bands at Moore Road and at Mockingbird
Lane. The City then changed to pavers throughout the intersection. The City is now looking
again at only the paver bands. Do not make any changes to the pavers until the City makes
a final decision.
6. Please review and provide backup calculations for the time of concentrations shown on the
drainage area map.
7. Provide a manhole at Station 0+00, Line A.
8. Coppell is concemed about the cover over Line B. Add notes to the paving plans regarding
the shallowness of both Line A and Line B. Based on the results of the previous drainage
decisions, Coppell is now evaluating draining Line B to Line C. The consultant is not
directed to make any changes to Line B at this time.
9. Clarify the HGL for line D.
10. Provide rip-rap at all outfalls where the velocity is greater than 10 fps.
11. Provide impact attinuators or guard rails wherever the slope along the roadway is steeper than
3: 1. Include the concrete slope protection details in the next submittal.
12. Note the appropriate adjustments for all manholes, water valves, etc. A letter from Dallas
Water Utilities is attached.
13. Show the existing railroad gates and signals in the topography for Moore Road and
Mockingbird Lane.
14. Check all laterals and trunk lines for paving subgrade clearance.
15. Label the low chord elevation of the bridge.
16. Coppell is again evaluating including sidewalks, bridge lights and special bridge railings
in the project. Please review the bridge layout sheets provided by Coppell and evaluate
the requirements for incorporating these items into the plans. Dallas County will inform
Coppell of Halff's evaluation, and Coppell will make a final decision on these items.
17. Final cross sections will be reviewed with the pre-fmal plan submittal.