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F-3. CONTRACT WITH STANTEC CONSULTING SERVICES, INC. FOR LOWER GILA RIVER FLOODPLAIN DELINEATION STUDY: AIRPORT ROAD TO PAINTED ROCK DAM POOL AREA Award Contract FCD 2012C017, Lower Gila River Floodplain Delineation Study: Airport Road to Painted Rock Dam Pool Area to Stantec Consulting Services, Inc. for professional engineering services. This contract amount is $612,535.54. The contract performance is 900 calendar days effective the date of the Notice to Proceed. This is a qualification-based selection in accordance with Maricopa County Procurement Code, Article 5, Paragraph 504. This reach of the Gila River is in the southwestern portion of Maricopa County. It includes area within the towns of Buckeye and Gila Bend and Unincorporated Maricopa County. There is an effective FEMA floodplain for this reach of the Gila River. The effective floodplain was delineated under three separate studies: by Cella Barr and Associates in 1990 from the Painted Rock Dam Pool Area to Gillespie Dam; by Dames and Moore in 1988 from Gillespie Dam to approximately 1.5 miles west of the State Route 85 Bridge; and, by Michael Baker Jr., Inc. in 1999 from 1.5 miles west of the State Route 85 Bridge to beyond the upstream limit of study at Airport Road. This re-delineation is being performed to reflect decreased 100-year peak flow rates in the river due to the raising of Roosevelt Dam (with dedicated flood storage) in the mid-1990s, more current and detailed topographic mapping, and improved hydraulic modeling methodology. Of the three studies reflecting the effective floodplain, only the Baker study reflects the lowered flow rates from the post-modified Roosevelt Dam. This agenda item impacts Supervisorial Districts 4 and 5. (C-69-13-011-5-00)