Loading...
Billingsley-CS040806 1111 H alff Associ 8616 NO PLAZA DRIVE DALL AS, TEXAS 75225 (214) 346 -6200 FAX (214) 739 -0095 ENGINEERS • ARCHITECTS • SCIENTISTS PLANNERS • SURVEYORS Federal Emergency Management Agency August 6, 2004 CIO PBS &J, Inc. 12101 Indian Creek Court AVO 18398 Beltsville, Maryland 20705 Attn.: Mr. Joe Martinenza Re: Request for a Conditional Letter of Map Revision on Grapevine Creek for a portion of a 158.6 -acre tract in the City of Coppell, Dallas County, Texas. Dear Mr. Martinenza: Enclosed you will find a technical report covering proposed site improvements for a portion of a 158.6 acre tract on Beltline Road in the City of Coppell, Dallas County, Texas. Grapevine Creek flows through this site. This report, submitted by Halff Associates, Inc. on behalf of the Billingsley Company, contains the technical data required for issuance of a Conditional Letter of Map Revision and a City of Coppell Floodplain Development Permit. Hard copies of the required HEC -2 hydraulic models, a disk containing input data files, and floodplain and floodway mapping can be found in Appendices A through P. Application and Certification forms are included in Section II. The analysis updates and refines City of Coppell and FEMA's effective models based on the proposed floodplain reclamation in the left overbank along Grapevine Creek and approximately 2000 feet of overbank swale for channel conveyance. The map revision also reflects reduced floodplain widths and no increase in 100 -year flood levels due to the proposed project. If you have any technical questions on this report, please contact me at Halff Associates, Inc. at 214 - 217 -6657. Administrative questions should be directed to Mr. Kenneth Griffin, P.E., City Engineer for the City of Coppell at 972- 304 -3679. Thank you for your consideration of this request. Yours very truly, HALFF ASSOCIATES, INC. a Walter E. Skipwith, P.E. Vice President Enclosures cc: Mr. Kenneth Griffin, P.E., City Engineer for the City of Coppell. Mr. Henry Billingsley, Billingsley Company. Mr. James Pritchard, P.E., Pritchard Associates, Inc. File: I:\18000s\ 18398 \doc \8398C LOM R -RPT. doc DALLAS • FORT WORTH • HOUSTON • McALLEN • AUSTIN • FRISCO • SAN ANTONIO TRANSPORTATION • WATER RESOURCES • LAND DEVELOPMENT • MUNICIPAL • ENVIRONMENTAL • STRUCTURAL MECHANICAL • ELECTRICAL • SURVEYING • GEOGRAPHIC INFORMATION SYSTEMS ARCHITECTURE • LANDSCAPE ARCHITECTURE • PLANNING