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FIRM-931019 (2)Federal Eimergency Management Agency CERTIFIED MAIL RETURN RECEIPT REQUESTED October 15, 1993 Washington, D.C. 20472 The Honorable Tom Morton Mayor of the City of Coppell Dallas and Denton Counties 255 Parkway P.O. Box 478 Coppell, Texas 75019 Dear Mayor Morton: PICT 19 1993 IN REPLY REFER TO: 115 -A Community No.: 480170 Map Panels Affected: FIRM: 0010 E On February 28, 1992, you were notified of proposed modified flood elevation determinations affecting the Flood Insurance Rate Map (FIRM) and Flood Insurance Study (FIS) report for the City of Coppell, Dallas and Denton Counties, Texas. The 90 -day appeal period that was initiated on March 13, 1992, when the Federal Emergency Management Agency (FEMA) published a notice of proposed Base (100 -year) Flood Elevations (BFEs) for your community in the Citizens Advocate, has elapsed. FEMA did receive an appeal from you during that 90 -day period. With letters dated June 4, 1992 and March 15, 1993, Mr. Kenneth M. Griffin, P.E., Coppell City Engineer, submitted technical data supporting requested changes to flood hazard and base map information shown on the December 18, 1991 preliminary FIRM for the City of Coppell. The technical data submitted in support of the appeal have been evaluated and the appeal has been resolved. All appropriate changes to flood hazard and base map information for the City of Coppell have been incorporated into the final effective FIS and FIRM. The enclosed proof copies of your community's FIS report and FIRM reflect the changes made as a result of the appeal. While evaluating your community's appeal of the preliminary FIS and FIRM, it has come to our attention that the locations of the bridges at Denton Tap Road and Bethel Road across Grapevine Creek were shown incorrectly on Flood Profiles 04P and 05P in the preliminary FIS report. This resulted in the incorrect placement of BFEs for Grapevine Creek from the downstream side of Denton Tap Road to approximately 1,700 feet upstream of Bethel Road. We have corrected the location of these two bridges on the flood profiles in the final FIS report and revised the BFEs on the FIRM to match the corrected profiles. These changes are reflected on the enclosed proof copies of the final FIS report and FIRM for the City of Coppell. 2 Enclosed please find as Exhibit A, a summary of the changes which have been incorporated into the ongoing revision, as well as a summary of additional changes that can be incorporated into your community's FIRM as a separate map revision upon submission of appropriate supporting information. The final BFEs will be published in the Federal Register as soon as possible. The modified BFEs and revised map panels, as referenced above, are effective as of April 15, 1994, and revise the FIRM which was in effect prior to that date. For insurance rating purposes, the community number and new suffix code for the panels being revised are indicated on the maps and must be used for all new policies and renewals. The modifications are pursuant to Section 206 of the Flood Disaster Protection Act of 1973 (P.L. 93 -234) and are in accordance with the National Flood Insurance Act of 1968, as amended, (Title XIII of the Housing and Urban Development Act of 1968, P.L. 90 -448), 42 U.S.C. 4001 -4128, and 44 CFR Part 65. Because of the modifications to the FIRM, and FIS report for your community made by this map revision, certain additional requirements must be met under Section 1361 of the National Insurance Flood Act of 1968, as amended, within 6 months from the date of this letter. Prior to April 15, 1994, your community is required, as a condition of continued eligibility in the National Flood Insurance Program (NFIP), to adopt or show evidence of adoption of floodplain management regulations that meet the standards of Section 60.3(d) of the NFIP regulations. These standards are the minimum requirements and do not supersede any State or local requirements of a more stringent nature. It must be emphasized that all of the standards specified in Section 60.3(d) of the NFIP regulations must be enacted in a legally enforceable document. This includes the adoption of the effective FIRM and FIS report to which the regulations apply and the modifications made by this map revision. Some of the standards should already have been enacted by your community. Any additional requirements can be met by taking one of the following actions: 1. Amend existing regulations to incorporate any additional require- ments of Section 60.3(d); 2. Adopt all of the standards of Section 60.3(d) into one new, comprehensive set of regulations; or, 3. Show evidence that regulations have previously been adopted that meet or exceed the minimum requirements of Section 60.3(d). Communities that fail to enact the necessary floodplain management regulations will be suspended from participation in the NFIP and subject to the prohibi- tions contained in Section 202(a) of the Act as amended. A Consultation Coordination Officer (CCO) has been designated to assist your community with any difficulties you may be encountering in enacting the 3 floodplain management regulations. The CCO will be the primary liaison between your community and FEMA. Your CCO is: Mr. Jim LeGrotte, Chief FERA, Natural & Technological Hazards Division Federal Regional Center 800 North Loop 288 Denton, Texas 76201 -3698 (817) 898 -5127 Any questions may be directed to your CCO. Sincerely, William R. Locke Chief, Risk Studies Division Federal Insurance Administration cc: Alan D. Ratliff, City Manager Kenneth M. Griffin, P.E., City Engineer — William A. Anderson, P.E., Dan M. Dowdey Associates, Inc. Phil Deaton, P.E., Carter & Burgess Bill Wallace, P.E., Nathan D. Maier Robert Porter, P.E., Don Tipton Engineers Jean Hansen, P.E., Albert H. Halff Associates Kevin Kendrick, P.E., Unzicker, Schnurbusch Associates Exhibit A The following changes were incorporated into the on -going revision: Corporate Limits- The corporate limits have been revised to reflect annexation ordinance numbers 88410, 88412, 88427, and 89430, as well as disannexation ordinance number 91504. For the annexed area along Denton Creek upstream of Interstate Route 121, flood hazard information was taken directly from the September 14, 1990, FIRM and FBFM panel 0260 for the unincorporated areas of Denton County. Street Names and Locations- Streets have been added and labelled in floodprone areas for the following subdivisions: Oakbend Addition, Shadow Woods Estates, Park Meadows Sections I and II, and Carter Estates. Also, the extension of Parkway Boulevard West of Denton Tap Road has been added. Grapevine Creek- Flood hazard information for Grapevine Creek has been revised to incorporate an August 10, 1992, Letter of Map Revision (LOMR) to reflect a channelization and drop structure project. Tributary G -1 of Grapevine Creek- The 100 -year floodplain boundary has been revised on the north side of the stream to reflect the completion of the Big Cedar Addition subdivision. Denton Creek- Flood.plain boundaries and the location of the corporate limits and streamline were adjusted to match with topographic maps submitted by your community to reflect the Gibbs Station, Lakes of Coppell, Lakewood Estates, and Villages of Coppell subdivisions. Elm Fork Trinity River - The area designated as 500 -year floodplain on the December 18, 1991, preliminary FIRM south of Beltline Road has been changed to 100 -year floodplain based on topographic maps submitted by your community. Cottonwood Branch- The floodplain boundaries and floodway were revised to incorporate a May, 26, 1986, LOMR to reflect the Villages of Cotton- wood subdivision. In addition, it was requested that flood hazard information for Grapevine Creek be revised to reflect the completion of the replacement of the bridge at Denton Tap Road and the completion of the Creek View Addition subdivision downstream of Denton Tap Road. However, the HEC -2 hydraulic backwater models submitted in support of these projects contained conflicting information. For the Denton Tap Road bridge replacement, the HEC -2 models were contained in an undated technical report entitled Floodplain Hydraulics Study, Grapevine Creek, Coppell. Texas. prepared for: As -Built Study of the Denton Tap Road Bridge Replacement prepared by Kimley -Horn and Associates, Inc. These models did not reflect the completion of the Creek View Addition. 4 For the Creek View Addition, the HEC -2 models were contained in a November 1992 technical report entitled Creek View Addition, As Built Conditions prepared by Nathan D. Maier, Consulting Engineers, Inc. These models re- flected the completion of both the Creek View Addition and the Denton Tap Road bridge replacement. However, the models for Creek View Addition have less detailed cross sectional information for the Denton Tap Road bridge than the models submitted for the Denton Tap Road. In addition, the 100 -year water surface elevations and floodway in the submitted Creek View Addition models do not tie -in to the HEC -2 models submitted by the City of Coppell used to prepare the December 18, 11991, preliminary FIRM. Thus, no changes have been incorporated for Grapevine Creek for the Denton Tap Road and Creek View Addition projects into the final FIRM. However, these changes can be incorporated into the community's FIRM as a separate map revision if the City of Coppell submits the appropriate addi- tional information to support such a revision in accordance with Part 65 of the NFIP regulations. At a minimum, the following information would be necessary: 1. HEC -2 models for both the 10 -, 50 -, 100 -, and 500 -year floods and floodway for Grapevine Creek reflecting both of these projects. This can be done by using the models submitted previously by the city which were used to prepare the preliminary FIRM (hereinafter referred to as the FIS model) as a base and incorporating revised cross section information for Creek View Addition and Denton Tap Road bridge replacement. It would appear that the more detailed cross section information for Denton Tap Road discussed above should be utilized. Please note that the 100 -year flood eleva- tions must tie -in within one -half foot upstream and downstream of the project area when compared to the FIS models in accordance with Subparagraph 65.6 (a)(2) of the NFIP regulations. The floodway widths must also tie -in upstream and downstream of the project area when compared to the FIS models. 2. Topographic mapping reflecting the completed projects with the revised 100- and 500 -year floodplain boundaries and floodway delineated. This mapping must be of suitable scale and topo- graphic definition to provide reasonable accuracy and must be certified to reflect existing conditions by a registered Pro- fessional Engineer or licensed Land Surveyor. 3. Certification that fill associated with the Creek View Addition exposed to moving floodwaters is covered with grass, vines, weeds, or similar vegetation in accordance with Subparagraph 65.5 (a)(6) of the NFIP regulations. Also, with his June 4, 1992, letter Mr. Griffin submitted "as- built" plans for the MacArthur Boulevard bridge that crosses Denton Creek and requested that the flood hazard information for Denton Creek be revised to reflect this completed project. In our December 18, 1992, letter, we requested that HEC -2 models reflecting the "as- built" MacArthur Boulevard bridge be submitted. However, this modelling was not submitted. Thus, flood hazards for Denton Q Creek have not been revised to reflect this project. However, this project can be incorporated into the Coppell FIRM as a separate map revision upon receipt of necessary data from the City of Coppell. The additional informa- tion needed to revise the Coppell FIRM to reflect the MacArthur Boulevard bridge includes HEC -2 models for Denton Creek reflecting the 10 -, 50 -, 100 -, and 500 -year floods and floodway revised to reflect the "as- built" MacArthur Boulevard bridge. These models can be prepared by using the models for Denton Creek submitted by the city used to prepare the preliminary FIRM as a base and revising it to reflect the bridge. Please note that the 100 -year water surface elevations and floodway must tie -in upstream and downstream of the project area when compared to the FIS model, as discussed above. FEDERAL EMERGENCY MANAGEMENT AGENCY FEDERAL INSURANCE ADMINISTRATION (44 CFR Part 67) Final Flood Elevation Determinations AGENCY: Federal Emergency Management Agency ACTION: Final rule. SUMMARY: Modified base (100 -year) flood elevations are determined for the com- munities listed below. These modified base (100 -year) flood elevations are the basis for the floodplain management measures that the community is required to either adopt or show evidence of being already in effect in order to qualify or remain qualified for participation in the National Flood Insurance Program (NFIP). EFFECTIVE DATE: The date of issuance of the Flood Insurance Rate Map (FIRM) showing modified base (100 -year) flood elevations, for the community. This date may be obtained by contacting the office where the maps are available for inspec- tion indicated on the table below. ADDRESSES: See table below. FOR FURTHER INFORMATION CONTACT: William R. Locke Chief, Risk Studies Division Federal Insurance Administration Federal Emergency Management Agency Washington, DC 20472 (202) 646 -2754 2 SUPPLEMENTARY INFORMATION: The Federal Emergency Management Agency gives notice of the final deter- minations of flood elevations for each community listed. Proposed base flood elevations or proposed modified base flood elevations have been published in the Federal Register for each community listed. This final rule is issued in accordance with Section 110 of the Flood Disaster Protection Act of 1968 (Title XIII of the Housing and Urban Devel- opment Act of 1968 (Pub. L. '90- 448)), 42 U.S.C. 4001 -4128, and 44 CFR Part 67. An opportunity for the community or individuals to appeal proposed deter- mination to or through the community for a period of ninety (90) days has been provided. The Agency has developed criteria for floodplain management in flood -prone areas in accordance with 44 CFR Part 60. Pursuant to the provisions of 5 USC 605(b), the Administrator, to whom authority has been delegated, by the Director, Federal Emergency Management Agency, hereby certifies for reasons set out in the proposed rule that the final flood elevation determinations, if promulgated, will not have a sig- nificant economic impact on a substantial number of small entities. Also, this rule is not a major rule under terms of Executive Order 12291, so no regulatory analyses have been prepared. It does not involve any collection of information for purposes of the Paperwork Reduction Act. List of Subjects in 44 CFR Part 67. Flood Insurance, Flood Plains. The authority citation for Part 67 continues to read as follows: Authority: 42 U.S.C. 4001 et seq., Reorganization Plan No. 3 of 1978, E.O. 12127. Interested lessees and owners of real property are encouraged to review the proof Flood Insurance Study and Flood Insurance Rate Map available at the address cited below for each community. The modified base (100 -year) flood elevations are finalized in the com- munities listed below. Elevations at selected locations in each community are shown. Any appeals of the proposed base flood elevations which were received have been resolved by the Agency. #Depth in feet above ground. State *Elevation in City /Town /County feet (NGVD) Source of Flooding and Location Modified Texas Coppell (City), Dallas and Denton Counties (FEMA Docket No. 7042) Elm Fork of Trinity River: Approximately 50 feet downstream of Beltline Road *440 Approximately 1,600 feet upstream of Sandy Lake Road *446 Grapevine Creek: Approximately 800 feet upstream of Ledbetter Road *440 Approximately 125 feet upstream of Southwestern Boulevard *507 Tributary G -1 of Grapevine Creek: At confluence with Grapevine Creek *492 Approximately 0.6 mile upstream of Bethel School Road *501 Denton Creek: Approximately 1.5 miles upstream of confluence with Elm Fork of Trinity River *447 At Interstate Route 121 *467 Old Denton Creek: At confluence with Denton Creek *453 At divergence from Denton Creek *454 Cottonwood Branch: At confluence with Denton Creek Approximately 1,250 feet upstream of Royal Lane *457 *519 Maps available for inspection at the Coppell Town Center, Engineering Depart- ment, 255 Parkway, Coppell, Texas.