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CF-Andrew Park 2-CS 970805Ill Halff Associates ENGINEERS · ARCHITECTS · SCIENTISTS PLANNERS · SURVEYORS August 5, 1997 AVO 1008-97-9151 Mr. Kenneth Griffin, P.E., City Engineer, Assistant City Manager and Director of Public Works The City of Coppell 255 Parkway Boulevard Coppell, Texas 75019 Fax: 1-972-304-3570 8616 NORTHWEST PLAZA DRIVE DALLAS, TEXAS 75225 (214) 739-0094 FAX (214) 739-0095 Re: Proposal for a Letter of Map Revision (LOMR) to the Federal Emergency Management Agency (FEMA) ,~ for Andrew Brown Jr. Park (East) in the City of Coppell, Texas, on behalf of the City of Coppell. Dear Mr. Griffin: HalffAssociates, Inc. is pleased to present this fee proposal for FEMA map revisions for Andrew Brown Jr. Park (East), in the City of Coppell, Texas. Generally, the services will consist of site surveying, revisions to a previously approved hydraulic study of the site (a 1992 Conditional Letter of Map Revision) to reflect as-built conditions, and the preparation of an application for a Letter of Map Revision (LOMR) to the Federal Emergency Management Agency. The entire hydraulic engineering, permitting and surveying effort can be completed for a lump sum fee of $18,100. A detailed work plan is attached as Exhibit A and an engineering fee estimate is included as Exhibit B. A suggested schedule is shown on exhibit C. Please call our offices at 214-739-0094, extension 220, if I can be of further help or if I can answer any questions regarding this proposal. We look forward to assisting you in the development of this important project. Please authorize by signing below and return one copy for our files. Sincerely, HALFF ASSOCIATES, INC. Enclosures. File: l:~avo\ 1008-97~9151 ~proposal.doc DALLAS · FORT WORTH Walter E Skipwith, P.E. Project Manager and Vice-President · HOUSTON · McALLEN TRANSPORTATION · WATER RESOURCES · LAND DEVELOPMENT · MUNICIPAL · ENVIRONMENTAL · STRUCTURAL MECHANICAL · ELECTRICAL · SURVEYING · GEOGRAPHIC INFORMATION SYSTEMS ~RCHITECTURE · I-~DSCAPE AR~CHITECTURE · PLANNING · ,_[ · II Halff Associates ENGINEERS · ARCHITECTS · SCIENTISTS PLANNERS · SURVEYORS Exhibit A Scope of Work Andrew Brown Park East LOMR in the City of Coppell, Texas for the City of Coppell AVO 1008-97-9151 August 5, 1997 Contents. I. Data Collection. II. As-built Survey. III. Proposed Hydraulics, Fully Developed Landuse. IV. Proposed Hydraulics, Existing Landuse V. LOMR Application Data Collection and Basemap Preparation. 1. Obtain park site plan(s) from City of Coppell. 2. Obtain approved grading plan(s) from City of Coppell. 3. Retrieve previously approved Conditional Letter of Map Revision (CLOMR) digital design files to plot topographic and boundary information, as well as proposed grading plan. 4. Create work map and plot topo at Andrew Brown Jr. Park (East). 5. Field visit to take photographs, inspect the site and possibly determine or confu'm CLOMR hydraulic coefficients. 6. 'Create location map for the final report. 7. Merge overall site plan(s) and grading plan(s) with topographic work map, annotate. 8. Create exhibit(s) for final report. II. As-built Survey. 1. Field survey spot elevations, at three sites at least, for LOMR application. 2. Process data and plot surveyed spot elevations. 3. Coordination with surveyors during as-built survey stage. This scope of work does not include any supervision of construction crews nor any involvement during the construction phase of the project. IAavo\1008-97~915 l\scope-a, do¢ I Halff Associates, Inc. Halff Associates ENGINEERS · ARCHITECTS ° SCIENTISTS PLANNERS · SURVEYORS IlL 1. As-built Hydraulics, Fully Developed (Ultimate) Landuse Conditions. Locate Proposed Fully Developed (Ultimate) Landuse Conditions model per the previously submitted Conditional Letter of Map Revision (CLOMR) for Andrew Brown Jr. Park East, Denton Creek only. 2. This proposal does not include any hydraulic modeling, fully developed (ultimate) landuse conditions, of Cottonwood Creek. 3. Run model to confirm pre-project flood levels per CLOMR request report. 4. Compare surveyed spot elevations with grading plan and proposed condition model per CLOMR application. 5. Modify the CLOMR proposed hydraulic model to reflect as-built conditions as needed, such as Possibly a pedestrian bridge near the Cottonwood Creek and Denton Creek confluence. 6. No additional hydraulic study work is included in this proposal to cover the possible extensive mitigation necessary to result in a no-rise condition. Should extensive mitigation be required, a special services task may need to be added to this proposal. 7. Execute, debug and plot the as-built hydraulic model. Check Manning's n-values used in CLOMR and all hydraulic coefficients that may apply. 8. Create water surface elevation and flow velocity comparison tables. 9. Create hard copy and digital copy of all hydraulic models. 10. Plot cross-sections and profile. 11. Write report section that pertains to fully developed (ultimate) landuse conditions. 12. Communication with City of Coppell should discrepancies between as-built conditions and CLOMR proposed conditions arise. Total number of meetings with the City of Coppell at all stages of the project not to exceed one (1) coordination meeting and one (1) final signatures meeting. IV. As-built Hydraulics, Existing Landuse Conditions for FEMA Submittal. 1. Retrieve CLOMR digital design files, flood plain delineations. 2. Retrieve digital hydraulic models from CLOMR project ^vo 11239, Denton Creek only. This proposal does not include any hydraulic modeling based on a different effective model than the one used in the previously approved CLOMR. 3. This proposal does not include any hydraulic modeling, existing landuse, of Cottonwood Creek. 4. Execute, debug and plot CLOMR models and compare to CLOMR results. 5. Create an as-built conditions existing landuse hydraulic model per the fully developed landuse model. 6. Execute, debug and plot the as-built conditions hydraulic model. 7. Create water surface elevation and flow velocity comparison tables. I:\avo\1008-97',915 l~scope-a.doc 2 HalffAssociate$, Inc. / Halff Associates ENGINEERS ° ARCHITECTS ° SCIENTISTS PLANNERS · SURVEYORS 8. Modify slightly both existing landuse model and fully developed landuse model to result in a no-rise condition in both models if necessary. Modifications do not include extensive re- design to compensate for adverse as-built conditions that may arise. 9. Locate, execute and debug the floodway model from the previously approved CLOMR application. 10. Modify floodway model to reflect the as-built existing landuse model above. 11. Create hard copy and digital copy of all as-built conditions hydraulic models. 12. This scope of work does not include any revisions to the Denton Creek or Cottonwood Creek hydraulic models for the purpose of improving the confluence of the 2 creeks in the FEMA models or for the purpose of correcting existing errors in the FEMA models. Those errors exist but are relevant only to areas upstream of Denton Tap Road. 13. This scope of work does not include any revisions to the Denton Creek or Cottonwood Creek hydrology for any reason, such as but not limited to improving the confluence of the 2 creeks in the FEMA models or for the purpose of correcting existing errors in the FEMA models. IV. LOMR Application A. Complete FEMA CLOMR forms, tables and attachments. 2. 3. 4. 5. 6. 7. 8. Obtain latest (7/97) FEMA forms and debug. Form 1 - Revision Requester and Community Official Form. Form 2 - Professional Engineer Certification Form. Form 4 - Riverine Hydraulic Analysis Form. Form 5 - Riverine/coastal Mapping Form. Form 6 - Channelization form. Form 7 - Bridge/culvert form, one per structure modified. Create a Form 4, Water Surface Elevation Check Table. B. Project site plan. Delineate the 100-year as-built conditions and the 500-year as-built conditions flood plain, compare with the CLOMR proposed flood plain. Edit site plan exhibit in CAD to create exhibit(s) for LOMR report. Plot exhibit(s). Create an plot a color flood plain delineations exhibit for clarity. C. Revise Flood Insurance Rate Map (FIRM) Community-Panel. Retrieve the proposed FIRM from CLOMR Avo 12239. Compare CLOMR flood plain delineations with as-built flood plain delineations. Revise delineations and create exhibit for LOMR application. ! :\avo\ 1008-97~915 l\scope-a.doc 3 Halff Associates. Inc. I Halff Associates ENGINEERS · ARCHITECTS · SCIENTISTS PLANNERS ° SURVEYORS D. Revise Flood Boundary and Floodway Map Community-Panel, if separate from FIRM. 2. 3. 4. Retrieve the proposed Floodway map from CLOMR Avo 12239. Compare CLOMR floodway delineations with as-built floodway delineations. Revise floodway delineations and create exhibit for LOMR application. If floodway map and FIRM map are combined, add as-built floodway delineation to the FIRM map. Eo Report and Other Exhibits. 2. 3. 4. 5. 10. 11. 12. Plot as-built cross-cross-sections, existing landuse hydraulics. Compare as-built cross-sections with CLOMR cross-sections plots. Plot as-built conditions profile, existing landuse hydraulics. Compare as-built profile versus CLOMR profile. Include copy of the Geotechnical report, compiled by Others and provided by the City of Coppell. Include copy of the approved US Corps of Engineers Wetland 404 permit. Report preparation and compiling. Publish a public notice of flood plain change in the official local City of Coppell newspaper. (~) Assemble and bind 4 copies of the LOMR report (City of Coppell, FEMA region VI, FEMA Washington D. C. offices, HalffAssociates Inc.). Meet with City representatives for review and signatures. Overnight submittal to FEMA headquarters. Coordination with FEMA during review stage. (2) Notes: (~) The public notice publishing fee is not included in the fee estimate. (2) FEMA Review fees are not included in the fee estimate. FEMA Library retrieval fees do not apply to this project and are not included in the fee estimate. I :\avo\1008-97\915 ! kscope-a, doc 4 Halff Associates, Inc. !il Halff Associates ENGINEERS · ARCHITECTS · SCIENTISTS PLANNERS · SURVEYORS Exhibit B Estimated Fees Andrew Brown Park East LOMR in the City of Coppell, Texas for the City of Coppell AVO 1008-97-9151 August 5, 1997 Task I. Data Collection. II. As-built Survey III. Proposed Hydraulics - Fully Developed Landuse IV. Proposed Hydraulics - Existing Landuse V. LOMR Application Budget $1,750 $650 $5,950 $3,500 $6,250 Lump Sum Total $18,100 Date 8/5/97 Halff ,~ssociates, Inc. [[ Halff Associates I1 ENGINEERS · ARCHITECTS · SCIENTISTS PLANNERS · SURVEYORS Exhibit C Estimated Schedule Andrew Brown Park East LOMR in the City of Coppell, Texas for the City of Coppell AVO 1008-97-9151 August 5, 1997 Task Date Notice to proceed on Data Collection Survey Fully Developed Landuse Hydraulics Existing Landuse Hydraulics Submittal of Final LOMR Report Monday 08/18/97 Monday 08/25/97 Monday 09/08/97 Monday 09/22/97 Monday 10/06/97 Monday 10/27/97 Note: Schedule will vary depending on weather conditions and availability of survey crews. A delay incurred at any point in time would delay the schedule accordingly. Date 8/5/97 Halff Associates, Inc.