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Eastern San Joaquin Groundwater Basin Groundwater Management Plan Northeastern San Joaquin County Section 8 Groundwater Banking Authority 105 Integrated Conjunctive Use Program The severity in the quantity and quality of flow in the San Joaquin River directly affects the operation of New Melones Reservoir. Quality and flow of the San Joaquin River has seriously deteriorated since the completion of the Friant Dam, the Delta Mendota Canal, and California Aqueduct. Inflow to the Delta from the San Joaquin River consists primarily of high saline drainage from farmlands and wetlands in the CVP's Westside service area. As a result, hundreds of thousands of tons of concentrated salt flow into the San Joaquin River each year. The SWRCB established flow and water quality standards on the San Joaquin River near Vernalis and directed the USBR to meet these standards. Consequently, the USBR has elected to meet the Vernalis standards with substantial releases from New Melones Reservoir. These releases for water quality purposes directly reduce the amount of water available for the Stockton East Water District and the Central San Joaquin Water Conservation District under their respective CVP interim contracts. The USBR and the Central Valley Regional Water Quality Control Board have shown little interest in addressing salt drainage or the restoration of flows in the San Joaquin River in a manner that does not harm San Joaquin County interests. Additionally, the Central Valley Improvement Act of 1992 (CVPIA) required more releases from the CVP for fish and wildlife system wide. The resulting actions have disproportionately affected New Melones Reservoir thus reducing the amount of water available for SEWD and CSJWCD. The USBR has made no real substantial progress towards revising the Interim Operations Plan for New Melones Reservoir, implementing source control programs for salinity in the CVP Westside service area, nor finding alternative sources for meeting the SEWD and CSJWCD water service contracts. CDWA and SDWA are directly affected by the quantity and quality of flow in the San Joaquin River. CDWA and SDWA have been the lead proponents of alternative means for the USBR to meet the Vernalis flow objective. While CDWA and SDWA recognize the use of New Melones to improve water quantity and flow in the San Joaquin River at Vernalis, it is neither a permanent solution nor a solution that is acceptable economically to San Joaquin County as a whole. San Joaquin County, Delta interests, and Eastern San Joaquin County have been supportive of measures that would restore the San Joaquin River through in-stream releases at Friant Dam, the establishment of water quality and flow standards upstream of Vernalis, and recirculation of Delta exports through the Delta-Mendota Canal and the San Joaquin River. Modeling has shown that any of the above options if implemented would free up water in New Melones for the SEWD/CSJWCD contract entitlements. 8.1.2 Calaveras River The Calaveras River is the primary surface water supply for the City of Stockton and SEWD. In 1963, the USACE constructed New Hogan Dam for flood control, recreation, and water supply purposes. The Calaveras River watershed consists of 363 square miles and stretches from the Sierra Nevada foothills to San Joaquin River in west Stockton. New Hogan Reservoir is primarily derived from rainfall and has a capacity of 317,000 af. The USACE operates New Hogan when flood control releases are necessary and reserves approximately 165,000 af of reservoir capacity for flood control storage. SEWD operates New Hogan and schedules releases at all other times. By agreement, SEWD is entitled to 56.5% of the yield to New Hogan with the remaining yield reserved for Calaveras County Water District (CCWD). Currently, SEWD utilizes CCWD’s unused supply. CCWD currently uses approximately 3,500 af per year and estimates it will use up to 5,300 af per year in 2040; however, growth in Calaveras County could spur interest in expanding use of its New Hogan supply (CCWD, 1996).