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F-3. RESOLUTION FOR GRANITE REEF WASH DRAINAGE IMPROVEMENTS Adopt Resolution FCD 2010R002 for the Granite Reef Wash Drainage Improvements (Project [265]), authorizing the Chief Engineer and General Manager of the Flood Control District of Maricopa County (District) to advertise, select, negotiate, and award contracts for engineering and construction services; negotiate Intergovernmental Agreements; include funding in the District’s Five-Year Capital Improvement Program, subject to Board ratification and approval. Flooding hazards threaten the developed area bounded approximately by the Central Arizona Project (CAP) to the north, Loop 101 to the east, Hayden Road to the west and the Salt River to the south. Flooding of property has occurred in the area, and 1,081 residential or commercial properties are located in the Granite Reef Wash floodplain. The City of Scottsdale completed a study of the area drainage features in January 2009, and the study concluded drainage capacity is insufficient. To mitigate this hazard, the study recommended the implementation of this Project, tentatively consisting of a large diameter conduit in Pima Road extending from Chaparral south to McKellips with associated laterals and inlets, and an outlet to the Salt River. This Agenda Item impacts Supervisory Districts 1 and 2. (C-69-10-078-6-00)

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F-3. AMENDMENT TO RESOLUTION FOR GRANITE REEF WASH DRAINAGE IMPROVEMENTS Adopt Resolution Amendment FCD 2010R002A for the Granite Reef Wash Drainage Improvements (Project [265]), which modifies the Project features to include storm drains, inlets, laterals, detention basins, and channels as necessary to provide the function of the Project at a lower cost. The watershed of Granite Reef Wash extends from the Arizona Canal on the north to the Salt River on the south, and from approximately Hayden Road on the west to the Loop 101 Freeway on the east. Approximately 1,081 residential and commercial properties are located within the floodplain of Granite Reef Wash. The City of Scottsdale completed flood hazard mitigation studies for the watershed in 2009 and 2014. The major feature of the 2009 study was a large diameter storm drain along the Pima Road corridor, which was assumed for Resolution FCD 2010R002. The 2014 study developed drainage improvement solutions that will meet the Project function at a much lower cost, using these features: storm drain inlets and laterals to be added to existing storm drains that convey flows to the west to Indian Bend Wash, detention basins, new storm drains, and channels. This Agenda Item impacts Supervisorial Districts 1 and 2. (C-69-10-078-6-01)