ST9601-CS 961015lg-IS-lggG 2:g3PW FRON P. 2
TEA GUE NALL AND PERKINS, INC.
CONSULTING ENGINEERS
2001 W. [r~ng BIrd, ir'~ing, 'l'~xi.~ 75061
972f254-1765 fax972t2:~l-4~48
MEMORANDUM
DATE: October 11, 1996 Via fax to: 972/304-3673
(2 pages)
TO: Ken Griffin, P.E. - City Engineer
Mike Martin, E.I.T. - Graduate Engineer
City of Coppel i
Teri Jones
RE: Wrangler Drive Reconstruction Project (Project # ST 96-01 )
City of Coppell
Project Muting at City of Coppell (10/02/96)
Thank you for taking the time last week to meet with us regarding the subject project. Your input
on the various questions which were presented was valuable and very much appreciated. The
following represents our understanding of how each issue should be addressed:
Rainfall Intensities. Storm water discharges for the Wrangler Drive project are to be
calculated using rainfall intensities based upon HYDRO-35, rather than TP-40.
2. Drainage Design for Lot I & 2, Blk. 5, Park West Commerce Center. The proposed
drainage design for the 29.39-acre parcel of land on the west side of Belt Line Road, b~vveen
Airline Drive and Wrangler Drive, as depicted on the Master Utility Layout plan prepared
by HalffAssociates, shows all the runoff disoharging to the existing storm drainage system
in Wrangler Drive. It is our understanding that the City will coordinate with HalffAssociates
to make certain that runoff from this property is collected into the various drainage systems,
in accordance with the previous drainage area delineations and/or drainage calculations
developed as part of the Belt Line Road storm drainage design.
3, Drainage Design/Grading Plans for the New Lincoln Business Center Development.
Plans for this tract, located at the southwest comer of the Wrangler Drive/Belt Line Road
intersection, are being prepared by BrockeRe-Davis-Drake, Inc., Consulting Engineers.
These plans will be provided to TNP for our review and use in preparing the design for the
Wrangler Road drainage improvements. The drainage design for the storm drain at Wrangler
10-1B-1996 2:03PM FROM P. 3
Memorandum - City of Coppell
October 11, 1996
Page Two
Drive and Belt Line Road was prepared assuming that approximately one-half of this tract
would &ain north to Wrangler Drive, while the southern portion of the tract was anticipated
to drain to the channel, to the south of the property. If it is determined that less storm water
is directed towards Wrangler Drive from this area than originally anticipated in the plans for
the Belt Line Road drainage improvements, the City should coordina~:e with the cleveloper's
engineer to delermine the capaciW of the system to the south into which the additional storm
water is being discharged.
4. ,/Airline Drive Storm Drainage System. The City will provide TNP with plans for the
existing Airline Drive storm drainage system. TNP will use the plans of the existing
improvements to determine whether or not the runoff from the 8.3 acres of land, norda of
Wrangler Drive and east of Enterprise Drive, was included in the design capacity for the
Airline Drive storm drainage system. If it was not included in the Airline Drive design, TNP
will evaluate the possibility of including capacity to accommodate runoff from this area in
the new storm sewer extension in Wrangler Drive, and/or explore other options, as necessary.
Freeport Parkway Storm Drainage System. TNP will analyze the capacity of the existing
Freeport Parkway storm drain system, under the conditions of a 100-year storm event, to
determine the allowable discharge from the Wrangler Drive drainage area into that system.
Allowable Spread of Water in Wrangler Drive. Stormwater from the 100-year frequency
storm will be allowed to flow in the street to a maximum depth of six (6") inches (from curb
to curb), with no provision for a "dry-lane" of traffic. Curb inlets in Wrangler Drive will be
designed and placed accordingly.
.XL-/' Curb Return Radii. The existing curb returns (30-foot radii) at the Wrangler Drive/Belt
Line Road intersection will not be removed or reconstructed in conjunction with this project.
All other curb returns on the project will also have 30-foot radii, with the exception of the
Freeport Parkway/Wrangler Drive intersection where the curb return radii will be 40 feet.
Schedule for Submittal of Schematic Plans and Report. The proposed submittal date for
the Schematic Design has been temporarily suspended until the plans for the Airline Drive
storm drainage design are provided to TNP. TN'P will provide a revised schedule to the City
once this information is received.
Should you have any questions or comments regarding our understanding of last week's meeting,
as stated above, please give us a call. Otherwise, we will wait to hear from you when the plans for
the Airline Drive drainage improvements are available and ready to be picked up. Thank you again
for your time and assistance.