Park West CC(4)-CS 960312nib ~ NORTHWESt- ~L'~A DR,VE
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DALLAS. TEXAS 75225
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ENGINEERS · ARCHITECTS . SCIENTISTS
PLANNERS · SURVEYORS
March 12, 1996
AVO 13447
City of Coppell
255 Parkway Blvd.
Coppell, Texas 75019
Attn: Michael Martin
..M .T. posi~r~
Re: ~roposed Rail Spur
at Park West Gommerce Genter
Dear Mike:
Enclosed is a set of plans for a proposed Railroad Spur and Trestle to serve MJ
Designs and Park West Commerce Center near Southwestern Boulevard in Coppell.
We are submitting these plans for your approval, as required by a contractual
agreement between Prentiss Properties and Dupey Management Corporation (MJ
Design). Please respond by stating your approval, or that the City of Coppell has no
jurisdiction in this matter.
I have also included a copy of the Conditional Letter of Map Revision from FEMA
and a letter from the Southern Pacific Railroad.
Please let me know if l can help in this approval process.
Sincerely,
HALFF ASSOCIATES, INC.
Dennis J. Chovan, P.E.
DALLAS · FORT WORTH · HOUSTON · ARLINGTON · McALLEN · CHICAGO
TRANSPORTATION · WATER RESOURCES · LAND DEVELOPMENT · MUNICIPAL · ENVIRONMENTAL · STRUCTURAL
MECHANICAL · ELECTRICAL · SURVEYING · GEOGRAPHIC INFORMATION SYSTEMS
ARCHITECTURE · LANDSCAPE ARCHITECTURE · PLANNING
E:IVED
JAN 3 o 1996
Southern Pacific Lines
Southern Pacific Building ' One Market Plaza · San Francisco, California 94105
F~ P. Reilly
Vice President and
Chief Engineer
948 150/369.2
3anuary 22, ].996
Mr. Grover C. Wilkins, Jr.
Halff Associates Inc.
8616 Northwest Plaza Drive
Dallas, TX 75225
Dear Grover,
Please refer to your letter of August 30, 1995, concerning
the proposed drill track to serve MJ Designs in the Parkwest
Commerce Center in the City of Copell.
The plans appear to be satis[actory.
Very truly,yours,
cc: Mr. J. W. Smith - Houston
Federal Emergency Management Agency.
Washington, D.C. 20472
AUG
The Honorable Mark Wolfe Case No.: 91-06-21R
Mayor of the City of Coppell Community: City of Coppell,
P.O. Box 478 ~ Dallas County,
Coppell, Texas 75019 Texas
Community No.: 480170
Dear Mayor Wolfe:
This is in reference to a letter dated December 14, 1990, from Ms. M. Shohre
Daneshmand, P.E., Acting Coppell City Engineer, requesting a conditional
Letter of Map Revision (LOMR) to reflect the effects on Grapevine Creek of a
proposed dual bridge project at Southwestern Boulevard and a proposed railroad
bridge project approximately 2,200 feet upstream of Southwestern Boulevard.
With her letter, Ms. Daneshmand submitted a technical report entitled Flood-
plain Study on Grapevine Creek Southwestern Boulevard to ~H-635 for the City
of Coppell, Texas, dated September 28, 1990, prepared by Albert H. Halff
Associates, Inc. This report included the following: HEC-2 models reflecting
existing and proposed conditions along Grapevine Creek for the 10-, 50-, 100-,
and 500-year floods, dated September 26, 1990; a description of the hydraulic
methodology; and delineations of the lO0-year floodplain boundaries and
floodway reflecting existing and proposed conditions. Ail necessary data to
process this request were received by February 12, 1991.
Fees necessary to process this conditional LOMR (a coral of $1,617) have been
received.
This request represents an addendum to a conditional LOMR issued on August 18,
1987, that concerned a proposed extension of the channelization on Grapevine
Creek and the addition of a concrete drop structure eo alleviate high channel
velocities at the upstream end of the channelization. In the August 18, 1987
conditional LOMR, it was stated that the Federal Emergency Management Agency
(FEMA) would not perform a revision to the effective Flood Insurance Study
(FIS) amd Flood Insurance Rate Map (FIRM) for the City of Coppell to reflect
the completed portion of the Grapevine Creek channel modification project
until the proposed drop structure was completed, due to the unstable condi-
tions created by the partially completed project. It is our understanding
that the proposed drop structure is not yet constructed, nor is it likely to
be built in the near future.
On the basis of our review of the submitted technical data, we determined that
the proposed Southwestern Boulevard to IH-635 project meets the minimum..
floodplain management criteria of the National Flobd Insurance Program (NFIP).
If the project were completed as proposed, a revision to the FIS and FIRM for
the City of Coppell would be warranted. This revision would reflect a
decrease in the Base (100-year) Flood Elevations (BFEs) and would modify the
2
lO0-year floodplain boundaries and floodway, as indicated by the submitted
technical data. Please note that this determination is based on conditions
that include the proposed drop structure and channelization. FEMA will not
revise your communityrs maps until all phases of the proposed project have
been completed.
This conditional LOMR is based on minimum floodplain management criteria
established under the NFIP. Your community is responsible for approving all
proposed floodplain development, including the project upon which this request
is based, and for ensuring that permits required by Federal or State law have
been received. State and. community officials, based on knowledge of local
conditions and in the interest of safety, may set higher standards for
construction or may limit development in floodplain areas. If the State of
Texas or the City of Coppell has adopted more restrictive or comprehensive
floodplain management criteria, those criteria take precedence over the
minimum NFIP requirements.
It should be noted that NFIP regulation Subparagraph 60.3(b)(7) requires
communities to "assure that the flood carrying capacity within the altered or
relocated portion of any watercourse is maintained." This provision is
incorporated into your community's existing floodplain management regulations;
consequently, responsibility for maintenance of the modified channel rests
with your community. Please be aware that FEMA may request that your com-
munity submit a description and schedule of channel maintenance activities.
Upon completion of the entire proposed project, your community may request a
revision to the effective FIS and FIRM. The revision request should be
submitted to our Region VI office and must include the data listed below:
1. Evidence of compliance with NFIP regulation Paragraph 65.4(b),
which states that "all requests for changes to effective maps
. must be made in writing by the community's Chief Executive
Officer (CEO) or an official designated by the CEO. Should the
CEO refuse to submit such a request on behalf of another party,
FEMA will agree to review it only if written evidence is provided
indicating the CEO or designee has been requested to do so."
2. "As-built" plans of the bridge construction project including drop
structure and channelization, certified by a registered
professional engineer.
3. HEC-2 hydraulic models of the 10-, 50-, 100-, and 500-year floods
and floodway representing "as-built" conditions. The elevations
in the "as-built" HEC-2 models must coincide with the effective
FIS elevations at the upstream and downstream ends of the project.
4. Delineation of the 100- and 500-year floodplain boundaries, the
floodway, and the locations and alignment of the cross sections
and flow line used in the hydraulic model.
a. This information should be shown on a map of suitable scale
and topographic definition to provide reasonable accuracy.
b. Ail items should be labeled for easy cross-referencing to
the hydraulic model and summary data.
5. ~ource data a~d engineering documentation for'the previousl~
mentioned items, as well as a bibliographic list of other sources
of information used.
Please note items 3, 4, and 5 have been submitted for proposed conditions; if
any changes take place during construction, these items must be resubmitted to
reflect ~as-built~ conditions.
We have enclosed a copy of Part 65 of the NFIP regulations, which further
describes the nature and extent of the material needed to support a request to
revise an effective FIS and FIRM. Compliance with the criteria outlined in
these documents will expedite FEMAts review process, thus allowing the FIS and
FIRM for the City of Coppell to be revised as appropriate, in a timely manner.
Should you have any questions regarding this matter, please do not hesitate to
contact the Chief, Natural and Technological Hazards Division of the Federal
Emergency Management Agency in Denton, Texas, at (817) 898-5127 or Matthew B.
Miller of our Headquarters staff in Washington, D.C., at (202) 646-3461.
Sincerely,
William R. Locke
Chief, Risk Studies Division
Federal Insurance Administration
Enclosure
cc: Ms. Jean Hansen, Albert H. Halff Associates, Inc.
Ms. M. Shohre Daneshmand, P.E.