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40 Contract #SD624AA irrigation, and flood protection. The Drainage District has jurisdiction of over 300 miles of drainage canals. Three primary outfalls, the Main Relief Canal, the North Relief Canal and the South Relief Canal, discharge approximately 100 million gallons of runoff over the watershed area into the IRL during an average day. Under the agreement, a Master Stormwater Management Plan will be developed, and will be comprised of retention/detention ponds, wetland treatment systems or other effective systems, all connected to the drainage area of the Main Relief Canal and/or South Relief Canal of the IRFWCD canal system, which will reduce flooding and remove stormwater pollutants. In addition, a NPDES compliance program will be provided. Subsequent master planning will address the North Relief Canal. The watersheds of the Main Relief Canal and the South Relief Canal are generally urbanized in the eastern one-third of the watershed and primarily agricultural in the western portion of the watershed. A large area in the central portion of the watersheds is designated 100 -year floodplain on FEMA maps, as proposed by Gee and Jenson Engineers in the late 1980s. Various lateral canals accept runoff from east -west sub -laterals spaced at one-half mile intervals. The topography is of low relief. The runoff is stored or attenuated within the 100 -year floodplain boundary prior to the outfalls being able to discharge it. Flooding occurs within the 100 -year floodplain in localized areas. Older developments within approximately 15% of the 50,000 acre watershed provide minimal or no water quality treatment. The discharge of freshwater runoff degrades the quality of the brackish estuarine environment, increases suspended solid loadings in seagrass areas, and pollutes the IRL. The project will be a cooperative effort between the St. Johns River Water Management District, Indian River County, IRFWCD, and the City of Vero Beach. In addition, Environmental Consulting & Technology, Inc. (ECT), will assist in the modeling effort. ECT is working under the direction of Calpine Corporation, a proposed for profit provider of energy in Indian River County. III. PROJECT TASKS Task No. 1— Data collection and preliminary modeling by ECT I -A. Data Collection/InventotyofSystem An investigation of existing field data, including known elevations of all necessary control structures, canal cross-sections, canal profile, and physical attributes of the primary IRFWCD outfall system shall be performed by COUNTY and Carter and Associates. This data will be given to ECT and used in the computer model developed by ECT in task 1-B outlined below. If needed, additional as -built data shall be obtained by the Consultant and input into the model at a later date by DISTRICT. Topographic information of the watershed shall be obtained from existing sources. I -B ECT will convert the version 3 SWMM model, originally developed by Williams, Hatfield, and Stoner, to the most current version of the SWMM model to be used by Page 11 of 19