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F-3. RESOLUTION FOR CAVE BUTTES DAM SEEPAGE REMEDIATION Adopt Resolution FCD 2009R009 for the Cave Buttes Dam Seepage Remediation (Project [#350]), 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, acquire rights-of-way, and include funding in the District’s Five-Year Capital Improvement Program. The estimated Project cost is $5,985,000. The Cave Buttes Dam and its three dikes are located North of SR-101L and West of Cave Creek Road. Cave Buttes Dam was constructed without a downstream seepage collection system and with a single 45 inch diameter outlet. Seepage appeared at the left (east) abutment area of the dam during a 1993 flood event in which the maximum reservoir level rose to within 22 feet of the crest elevation of the emergency spillway. The District has identified a need to remediate Cave Buttes Dam and two dikes by constructing a downstream seepage collection system comprised of a filter-drain system with relief wells and one additional outlet to drain the dam in less time. This Project will implement permanent dam safety measures in the interest of risk reduction and public safety. This item impacts Supervisory Districts 3, 4, and 5. (C-69-10-006-6-00)