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Table 4.9-8 Sacramento San Joaquin Delta Water Quality Control Plan Standards for Delta Inflow and Outflow, Chloride, and Electrical Conductivity. Location Parameter Standard Description Sacramento River at Rio Vista Flow Rate 4,500 cfs d Minimum monthly average flow rate(cfs) Minimum Monthly average(cfs).For the May-Jan objectives,if the value is less than Net Delta Outflowor equal to 5,000 cfs,the 7-day running Delta Outflow Index 8,000 cfs e average shall not be less than 1,000 cfs below the value; if the value is greater than 5,000 cfs,the 7-day running average shall not be less than 80%of the value. a Number of days per year is dependent on water year type.Wet=>240 days;Above Normal=> 190 days; Below Normal=> 175 days; Dry=> 165 days;Critical=> 155 days. b EC standard is relaxed before August 15 depending on water year type.Wet=>no relaxation;Above Normal=>on July 1 relaxed to 0.63;Below Normal=>on June 20 relaxed to 1.14; Dry=>on June 15 relaxed to 1.67;Critical=>on April 1 relaxed to 2.78 ° EC standard varies by month.October=> 19.0; November-December=> 15.5;January=> 12.5; February-March=>8.0;April-May=> 11.0 d Flow rate varies by month and water year type.September=>all year types=3,000 cfs;October=>Wet,Above Normal,Below Normal &Dry year types=4,000 cfs;October=>Critical year type=3,000 cfs;November&December=>Wet,Above Normal, Below Normal& Dry year types=4,500 cfs; November&December=>Critical year type=3,500 cfs e Index varies by month and water year type.January=>all year types=4,500 cfs or 6,000 cfs depending on Eight River Index; February through June=>all year types=variable between 7,100 cfs and 4,000 cfs depending on Eight River Index;July=>Wet&Above Normal year types=8,000 cfs;July=:>Below Normal year type=6,500 cfs;July=>Dry year type=5,000 cfs;July=>Critical year type =4,000 cfs;August=>Wet,Above Normal&Below Normal year types=4,000 cfs;August=:>Dry year type=3,500 cfs;August=> Critical year type=3,000 cfs;September=:>all year types=3,000 cfs;October=:>Wet,Above Normal,Below Normal&Dry year types =4,000 cfs;October=>Critical year type=3,000 cfs; November&December=>Wet,Above Normal,Below Normal&Dry year types= 4,500 cfs; November&December=:>Critical year type=3,500 cfs Source: LWA 2007 Water Quality Control Plan for the Control of Temperature in the Coastal and Interstate Waters and Enclosed Bays and Estuaries of California (Thermal Plan) and SWRCB Resolution 5-00-192 (if any Exception) The Thermal Plan sets limits for"thermal waste" and"elevated temperature waste"discharged into coastal and interstate waters and enclosed bays and estuaries of California(SWRCB 1975). The Thermal Plan also empowers RWQCBs, with SWRCB concurrence, to grant an exception from the plan's specific water quality objectives (SWRCB 1975). Estuarine waters are considered to extend from"a bay or the open ocean to the upstream limit of tidal action"(SWRCB 1975). The San Joaquin River is subject to tidal action and,therefore, the Thermal Plan's water temperature differential objectives for effluent and receiving waters generally apply to discharges within this reach of the river. Objective 5A(1)a of the Thermal Plan prohibits a waste discharge to estuaries that exceeds the natural receiving water temperature by more than 20°F. Objective 5A(1)b prohibits a waste discharge that would cause more than a 1°F (0.56°C)rise in more than 25%of the receiving water cross-section at the discharge location. Objective 5A(I)c states that no discharge shall cause a surface water temperature rise of more than 4°F above the natural receiving water temperature at any time. DER EDAW City of Manteca 4.9-19 Hydrology and Water Quality