Northlake 635(8)-CS 870217 POWELL&POWELL 0
Engineers and Consultants . i
i'
W. J. Powell P.E. -- 1925-1967
\V. Llewellyn Powell P [-2. February 17, 1987
Richard 1.. Powell P.E.
J. Michac'l .Xtillican P.E.
Michael D. McKerlzie
RE: P&P No. 3072-86-9-7
Lot 2, Block D, Northlake 635 Business
Park, Coppell, Texas
Ms. Shohre Daneshmand
City of Coppell
255 Parkway Boulevard
Coppell, TX 75019
Dear Ms. Daneshmand:
We have reviewed the comments made by Ginn, Inc. (acting City Engineers) on the
referenced project (comment letter dated Jan. 30, ]987, enclosed) and offer the
following corn m ents:
1. The Lot and Block number of the tract (Lot 2, Block D) are correct on the prints
of the Final Plat which are being signed by the owner at this time and are to be
forwarded to the City.
2. Your office, during the review process of the Final Plat, indicated that the fire
lane was not to be shown on the Plat. The fire lane has been indicated on the
approved Site Plat for the site prepared by WSI Architects.
3. There are no open storage areas on this site.
4. A screening wall is being proposed at the northeast corner of the building which
would screen the dock area from Crestisde Drive. This wall is shown on the Site
Plan.
5. Mr. Steve Goram, Director of Public Works, instructed us that, other than those
utilities that are located within the easement dedicated on-site for placement
of the water meter, the utilities and storm drainage on this site will not be
maintained by the City and will not be located in City easements.
6. Mr. Troy Glidewell, City Fire Marshal], advised WSI Architects that the fire
lane turnaround shown on the Site Plan is adequate.
7. Parking for the future building expansion will be provided by the construction of
additional parking south of the building. The number of spaces will be required
to conform to City of Coppell parking requirements.
8. The major and street drainage systems for the North]ake 635 Business Park
were designed using a 100-year storm frequency based on Technical Paper 25.
At the time of the development of the business park, the City and Ginn were
3079 ,/0 ~ North Central Expressway, Suite 1130 / Dallas, Texas 75204 / (214) 5224660
Ms. Shohre Daneshmand
February 17, 1987
Page 2
developing the current Subdivision Ordinance. Since the ordinance was not
complete, Ginn, Inc. instructed P&P to design the park drainage systems based
on TP-25, which is used by the City of Dallas and several other municipalities in
this area. Because the systems into which this site drains were designed using
TP-25, P&P likewise designed the on-site storm sewer and based site runoff
calculations from TP-25.
9. The Site Plan indicates 15' radii to be constructed at both drives.
10. The City Public Works Department and Fire Marshall both reviewed and
approved the water and sanitary sewer plan for the site which shows 6" fire
hydrant leads. All water lines on-site are to be 8" if they supply a fire hydrant
and another water service.
]1. A type "B" headwall as shown in the City of Coppell Standard Details was
indicated to be constructed at the outfall of the proposed 24" storm sewer.
Because of the relatively slow design velocities in the channel (4.7 FPS) we feel
no rip rap on the channel side slope or bottom is necessary at this location.
12. The future parking south of the building has not been designed, and therefore,
we do not know at this time whether pavement will be constructed in the 13'
Texas Power & Light Co. easement. I-{owever, we find nothing in the
Subdivision Ordinance, the Final Plat Owner's Certificate, or the document
which dedicated this easement, that restricts the construction of parking within
the easement as long as Texas Power & Light has access to the easement for
maintenance purposes. This access will continue to be provided if parking is
constructed in the area south of the building.
13. The City Subdivision Ordinance, Appendix A, Section III-A-9 states that sanitary
sewers shall be constructed of ductile iron or polyvinyl chloride pipe.
14. The City Subdivision Ordinance does state that P.V.C. water mains of 8-inch
diameter and smaller shall be Class 200, D.R. 14. Please inform us if your wish
any action to be taken on this item.
In responding to the issues raised in the Ginn letter, we respectfully wish to point out
that the Final Plat, Site Plan, and Engineering Plans for this site have already been
reviewed several times by City Staff; and have been approved by the City Staff, the
Planning and Zoning Commission and the City Council. It therefore seems to us that,
after these thorough City reviews which were conducted at a high level of professional
cooperation between the various City departments and our firm, that it is rather belated
to be submitting a list of design revisions to us after we had understood that the plans for
the site were approved.
3072/0127
Ms. Shohre Daneshmand
February 17, 1987
Page 3
If you have any questions regarding this letter, or need any further explanation on any of
the items above, please contact Mr Jim Koch of this office.
Very sincerely,
POWELL & POWEI. L
J. Michael Milliean
JMM:ck
enclosure
cc: .Mr Ray Garrison - WSI
Mr Tom Cook - Vantage
Mr. Subash Gaitonde -Vantage
Mr. Ed McGuire - Bob Moore Construction
Mr. Gabe Favre - C-inn, Inc.
3072/0127