Lam Lee-CS 990111 , , Coppell, Texas 75019
/,/~/~ The City With A Beautiful Future 972-462-0022
~_..__// ff___.~ P.O. BOX478
(~/__/~ CO PPELL, TEXAS 75019
January 11, 1999
Christopher M. Jones, P.E.
Pacheco Koch Consulting Engineers, Inc.
9401 LBJ Freeway, Suite 300
Dallas, Texas 75243
RE: Lam Lee Addition No. 1
Dear Mr. Jones:
The City of Coppell has reviewed the referenced plans and has the following comments to
offer:
1. All left-turn lanes and medians should have brick pavers in the nose per the City
Streetscape Plan.
2. On the grading and drainage plan, please lighten the contour information and darken the
proposed drainage system.
3. Clarify what the drainage line running south from the proposed building is intended to
drain (label, etc.).
4. All improvements in the floodplain will require a floodplain permit.
5. Regarding the runoff calculations, the Dallas Drainage Design Manual specifies an
average runoff coefficient for office, commercial and industrial development of 0.90.
Provide support (i.e. reference) for using different runoff coefficients for different
drainage areas or use the average C-factor.
6. Provide a detail for the installation of a wye into an existing drainage system.
7. Provide the HGL elevation at the inlet for all laterals tying into an existing storm drain.
8. The existing curb inlet located at the proposed northern entrance off of Royal Lane needs
to be moved upstream and kept as a curb inlet. Grate inlets in public right-of-way are to
be avoided per the Dallas Drainage Design Manual.
9. All public storm drain pipe will be Class III RCP. Alternative materials for private storm
drain require approval from the City Engineer.
10. Consider making the sanitary sewer service connection to the south instead of to the east
to avoid the need for a dry bore underneath paving. Also, provide a wastewater access
device on the sanitary sewer service at the right-of-way line.
11. The proposed water line should be located such that it is not underneath the proposed
T.U. Electric transformer.
12. Show the location of all retaining walls on the paving plan.
13. Provide a bollard at the curb face for the proposed concrete flUme.
14. The proposed retaining wall detail needs approval from City Building Inspections. '
15. All fire hydrant locations must be approved by the City Fire Marshal, Travis Crump. He
can be reached at (972)304-3503.
There are various other minor comments throughout the plans. When all comments have been
addressed, please return these marked plans and two sets of revised plans to the City for,
review. If you have any questions, please contact me at (972) 304-7019.
Sincerely,
Kent M. Collins, E.I.T.
Graduate Engineer