Loading...
FIRM-94011301 -13 -1994 11 :22AM FROM DALLASCOCOMMCT TO 93930948 P.02 January 13, 1994 Federal Emergency Management: Agency 500 'C' Street S.W. /Room 418 Washington, D.C. 20472 Re: Case Number 93 -06 -2678, Request for a Conditional Letter of Map Revision on Grapevine Springs in Coppell, 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"vnginally constructed over 50 years agog by the WPA, but fell into disrepair and reverted to the original owners,therefore,the reacquisition of the property. The park was the site of a historic treaty signing between Sam Houston and the Forth Texas Indian Tribes in 1943 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 4ft Dallas County and the City of Coppell have been carefully removing years of accumulated 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, FEMA is requesting a re- modeling of Grapevine Creek hydraulics (HEC -2) of both the pre - construction 01 -13 -1994 11 :23AM FROM DALLASCOCOMMCT TO 93930948 P.03 Federal Emergency Management: Agency January 13, 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 true conditions for this reach of Grapevine Creek. We believe that our knowledge of this site's unique conditions, ORG14diu ) eb enables us to make this judgement. J 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 2141393 -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, Allen Bud Beene, P.E. Director of Public Works Dallas County, Texas ABBIKMG. jdj xe: Jack Quarles, FEMA Region VI David Preusch, P.E., Michael Baker Inc. Neal Chisholm, P.E., Graham Associates Kenneth M. Griffin, P.E. City Engineer City of Coppell, Texas TOTAL P.03