Hollows-CS 980104 Coppell. Texas 75019
The City With A Beautiful Future 972-462-0022
(~ ~._~,,,/ RO. BOX 478
~ COPPELL. TEXAS 75019
January 4, 1998
Mr. Richard Hovas, P.E.
Tipton Engineering, Inc.
6330 Broadway Blvd, Suite C
Garland, Texas 75043
RE: The Hollows at Northlake Woodlands
Dear Mr. Hovas:
The City of Coppell has received and reviewed the referenced plans and has the
following comments to offer:
1. On the Final Plat, please show an access easement for the 24' Emergency
Access Road.
2. For all details where the City of Coppell has Standard Construction Details,
please refer to the standard and do not show a separate detail (e.g. paving cross
sections, joint sealant, etc.)
3. For the vertical alignment of Sora Drive, try to adjust the vertical curvature
such that the slope approaching Crestview Drive is less severe.
4. Consider moving the lowpoint of Crestview Drive to the north such that positive
overflow would be carried by the alley. The concrete flume between lots 36 and
37 of Block A would then not be needed.
5. The emergency access drive provided off of Hidden Hollow Court will be
constructed according to the requirements of City of Coppell Fire Marshall.
6. The minimum time of concentration for hydrologic computations should be 10
minutes.
7. There is concern regarding how the drainage plan is handling the flow of water
to natural low points. Specifically, there are areas in Block C Lot 2 and in the
T.P.&L. easement that drain toward this site at a specific lowpoint. The
drainage plan does not show how the water is handled at these points. These
storm flows should be handled through additional inlets and storm drain pipe.
8. Based on existing grades, a portion of the site should drain to the south. Provide
an analysis of the downstream drainage system (beginning with the 7'x4' box
and including a routing through the downstream ponding system) verifying that
the system can handle all of the storm drainage from this site. Also, indicate
what impact the additional flow will have on the downstream developments
under Q~0o conditions.
9. Consider moving the inlet located in front of Block A Lot 33, at the end of
Hidden Hollow Court, such that it will not interfere with residential driveway
locations.
10. The minimum lateral size for a low point inlet is a 21" RCP.
11. Provide flowline and grades for all grade-to-drain ditches.
12. Provide a letter of permission from TP&L stating that you are allowed to do
grading work in the TP&L easement.
13. Indicate who will be responsible for maintaining proposed drainage ditches.
14. Show concrete collars at all storm drain pipe size changes.
15. Use the City of Coppell Standard Construction Details for the drop inlet and
omit the concrete apron.
16. Will an irrigation meter be needed to maintain common areas? If so, indicate the
size and location of the meter.
17. In Crestview Drive, curve the sanitary sewer line to keep the line behind the
curb.
18. On the grading plan, show top of curb elevations along Sofa Drive.
19. Sanitary sewer cleanouts must not be spaced at more than 200' as per City of
Coppell Subdivision Ordinance.
20. There are numerous inlets that should be moved such that the surface drainage is
intercepted prior to flowing into Crestview Drive. Refer to the marked plans
for specific locations.
21. All fire hydrant locations must be approved by the City Fire Marshall, Travis
Crump. He can be reached at (972)304-3503.
There are various other minor comments throughout the plans. Once these comments
have been addressed, these marked plans and two sets of revised plans should be
resubmitted to the City for review. If you should have any questions concerning these
comments, please contact me at (972) 304-7019.
Sincerely,
Kent M. Collins, E.I.T.