DR9305-CS 940121DALLAS COUNTY
PUBLIC WORKS
January 21, 1994
Federal Emergency Management Agency
500 'C' Street S.W./Room 418
Washington, D.C. 20472
Re:
Case Number 93-06-267R, Request for a Conditional Letter of
Map Revision on Grapevine Springs in CoppeR, Texas
· Grapevine Springs Park Project
Dear Mr. Magnotti:
We realize that you are probably not familiar with this project, therefore, we would like to take
the time to present some of the background information about the Grapevine Springs Park
Project.
The Grapevine Springs Park site was acquired by the Dallas County Park Dept. in 1991. It will
be operated and maintained by the City of Coppell Parks and Recreation Department. The Park
is only 15.5 acres and is located within walking distance of the center of 'oldtown' Coppell.
The park originally constructed over 50 years ago, by the WPA, but fell into disrepair and
reverted to the original owners therefore the reacquisifion of the property. The park was the
site of a historic treaty signing between Sam Houston and the North Texas Indian Tribes in 1843
thus circumventing General Santa Ana's scheme to enlist the tribes in a second invasion of
Texas. (Please note that in the State of Texas, Sam Houston is regarded as the father of the
Texas Republic and everything he touched is highly regarded.) It is hoped that the Grapevine
Springs Park will eventually be placed on the National Register of Historic Places, but we would
like to clean-up the place before applying.
For the last 2 years the Dallas County and the City of Coppell have been carefully removing
years of accumulat~ debris, sediment and undergrowth from the Park's native stone features.
The park is centered on Grapevine Creek and an old dam forms a shallow pool in the creek
channel. This pool is one of the natural focal points of the park, however, over the years the
creek has been eroding a new channel south of the pool. This new channel by-passes the old
dam and the erosion is starting to consume parts of the park as well as deposit sediment in the
creek channel downstream. The erosion in the bypass channel will eventually drain the existing
pool. As part of the park restoration, we are attempting to return the site to its original
conditions; which includes keeping water in the pool. We have included a site plan with this
letter to help show the situation.
However, the purpose of this letter is not to update FEMA on our local project, but rather we
are writing in response to FEMA's letter dated November 11, 1993 requesting additional data
for the review of the Grapevine Springs Park Erosion Control Project. Specifically, FF. MA is
requesting a re-modeling of Grapevine Creek hydraulics (HEC-2) of both the pre-construction
411 Elm Street Dallas, Texas 75202 653-7151
Federal Emergency Management Agency
January 21, 1994
Page two
and proposed conditions without dividing the flood discharge between the main and bypass
channels. This re-modeling is requested for the 10, 50, 100 and 500 year discharges and for
the 100 year floodway. Also, re-mapping of the floodplains and floodway is being requested
for this condition. In addition, a correction in the 10 and 50 year model's starting water surface
elevation has also been requested, however this minor correction can not be made until the larger
issue of the main channel - bypass channel split flow modeling'verses non-split modeling has
been resolved.
We believe that the information requested in FEMA's letter dated November 11, 1993, is to
satisfy a 'personal preference' and not to satisfy one of FEMA's regulations. We believe that
we have provided a technical analysis that best represents the tree conditions for this reach of
Grapevine Creek. We believe that our knowledge of this site's unique conditions enables us to
make this judgement.
We request that the 90 day time period be suspended until FEMA has had a chance to respond
to this letter.
If you have any questions about the project please contact either Mr. Allen Bud Beene, P.E.,
Director of Public Works of Dallas County at 214/653-7151 or contact Mr. Ken Griffin, P.E.,
Coppell's City Engineer at 214/393-1016. We STRONGLY suggest a direct dialogue be
established between FEMA-Washington and the local jurisdictions on this project. Thank you
for your consideration of our request.
Sincerely,
Director of Public Works
Dallas County, Texas
City Engineer
City of Coppell, Texas
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lack Quarles, FEMA Region VI
David Preusch, P.E., Michael Baker Inc.
Ne. al Chisholm, P.E., Graham Associates
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