Coppell Greens 2-CS 990816
~he City With A Beautiful Future
'.O. BOX 478
:OPPELL,TEXAS 75019
P.O. Box 478
Coppell, Texas 75019
972-462-0022
August 16, 1999
Mr. William Anderson
Dowdey, Anderson & Associates, Inc.
5225 Village Creek Dr., Suite 200
Plano, TX 75093
IZE: Coppell Greens Phase 2
Dear Mr. Anderson:
The City of Coppell has received and reviewed the referenced plans and has the
following comments to offer:
1. Consider locating curb inlets on the property line where possible to allow flexibility
in the driveway locations for the adjacent lots.
2. Provide a north arrow on each sheet.
3. The minimum time of concentration for drainage calculations is 10 minutes per~the
City of Coppell Subdivision Ordinance. Longer Ti's may be used if calculations are
provided supporting their use.
4. For the headwalls on lines "J" and "G", an extended headwall may be needed to
support the slope. Also, show slopes to the headwall at all appropriate locations.
5. In the storm drain profiles, show pipe connections, all inlet locations, etc. Provide
concrete collars at all pipe size changes.
6. The minimum grade for storm drain pipe is 0.3% per the Dallas Drainage Design
Manual.
7. Provide an additional manhole on Line "L" as shown on the mark-ups.
8. On the utility plan, make sure to maintain 10' of separation between water mains and
sanitary sewer lines.
9: All sanitary sewer manholes deeper than 12 '/Z feet need to be 5' in diameter.
10. Make sure that the grading plan matches the proposed drainage area map.
There are various other comments throughout the plans. Once these comments have been
addressed, these marked plans and two sets of revised plans should be submitted to the
City for review. If you have any questions concerning these comments, contact me at
(972) 304-7019.
Sincerely,
Kent M. Collins, P.E.