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Eastern San Joaquin Groundwater Basin Groundwater Management Plan 8.1.3 Mokelumne River The Mokelumne River watershed encompasses approximately 660 square miles stretching from the high Sierra Nevadas westward to the Delta. Major facilities located on the Mokelumne are the Salt Springs Reservoir on the North Fork of the Mokelumne and the Pardee and Camanche Reservoirs on the rivers main stem. Salt Springs Reservoir, the largest of seven Pacific Gas & Electric (PG&E) reservoirs (Project 137), was built in 1963 and is operated for hydropower generation. Pardee and Camanche are both owned by EBMUD. Pardee Reservoir, which is upstream from Camanche, has a capacity of 197,950 of and is operated as a water supply reservoir. Reservoir water from Pardee is conveyed by the Mokelumne River Aqueducts to the EBMUD service area some 82 mile away. Camanche Reservoir, with a capacity of 417,120 af, is operated for flood control and also to meet instream flow requirements and down stream entitlements. Snowmelt comprises a large portion of the watersheds runoff. Both Pardee and Camanche generate incidental hydro power at 30 MW and 9.9 MW respectively. (EBMUD, Urban Water Management Plan 2000) In-stream flow requirements and water rights on the Mokelumne form a complex hierarchy of entitlements. Under the Joint Settlement Agreement on the Lower Mokelumne River Project (JSA), minimum in-stream flows, reservoir pool elevations, and fisheries enhancements are implemented conditional to the FERC Permit of Pardee and Camanche Reservoirs. Subsequently, the D-1641 of the SWRCB reaffirms the validity of the JSA commitment to establishing adequate Bay-Delta flows and water quality. Additionally, provisions in the Lodi Decree protect groundwater levels in the City of Lodi from flow related deficiencies and inadequate groundwater levels. Table 8-1 depicts the target JSA release and in-stream flow requirements. Table 8-1 Lower Mokelumne In-stream Flow Requirements Year Type Requirements Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Annual (cfs) (af) Normal 325 325 325 325 325 325 325 325 325 100 100 100 194,000 Below Normal Minimum 250 250 250 250 250 250 250 250 250 100 100 100 154,000 Camanche Dry Reservoir 220 220 220 220 220 220 220 220 100 100 100 100 130,000 Release Critical 115 130 130 130 130 130 130 100 100 100 100 100 80,000 Normal 100 100 100 100 100 100 150 300 300 25 25 25 86,000 Below Normal Expected Flow 100 100 100 100 100 100 150 200 200 20 20 20 73,000 below Dry Woodbridge 80 80 80 80 80 80 150 150 20 20 20 20 52,000 Diversion Dam Critical 75 75 75 75 75 75 75 15 15 15 15 15 52,000 Note:Minimum releases from Camanche Reservoir are approximately and should not be used to determine the actual available quantity of water available for new uses on the Mokelumne River. Source:MORE WATER Project Phase I-Reconnaissance Study Summary Report,2004 EBMUD must also meet the requirements of both upstream and downstream water right holders. Increasing demands of upstream developments in Alpine, Amador, and Calaveras Counties are recognized by the SWRCB as having priority to Mokelumne River water. Downstream users served by Camanche Reservoir include WID and NSJWCD. WID holds both pre and post-1914 water rights. In years when Mokelumne inflow is greater than 375,000 af, WID is entitled to 60,000 af. When Mokelumne inflow is less that 375,000 af, WID is entitled less than 60,000 of to a minimum of 39,000 af. Through conservation and irrigation efficiency efforts, WID has made 6,000 of per year available to the City of Lodi. Under the agreement, the Northeastern San Joaquin County Section 8 Groundwater Banking Authority 106 Integrated Conjunctive Use Program