Lower Mokelumne River l Description of Watershed l Beneficial Uses l Pollution Sources l Potential Pollution Management Strategies

Description of Watershed l Approximate Area l Land Uses l Typical Flow Rates l Major Fish Species

Approximate Area l Topography –Mountainous –Flat l Water Sources –Upper Mokelumne River EBMUD Melting snow l Drainage Area = 627 mi 2

Land Uses l Agriculture70% l Urban/Suburban10% l Undeveloped20%

Typical Flow Rates l 50% Exceeds 437 l 10% Exceeds1,680 l Max Flow (1986)6,060 l Min Flow (1977) 23 l Avg. Annual Flow730 l Avg. Daily Flow876 l Dry Weather Flow105

Major Fish Species l * Special Concern Species l Chinook Salmon l Rainbow Trout l Green Sturgeon* l Pacific Lamprey l River Lamprey* l Prickly Sculpin l Sacramento Blackfish l Sacramento Squawfish l Sacramento Sucker l Tule Perch l White Sturgeon

Beneficial Uses l Agriculture l Recreation l Migration l Spawning l Wildlife Habitat l Power Generation

Agriculture l Irrigation (Canals) –58 MGD to Woodbridge Irrigation District l Stock Watering –Camanche Dam Capacity 431,500 ac-ft –Woodbridge Dam 2,464 ac-ft

Recreation l Contact –Lodi Lake –Camanche Reservoir –New Hope Landing l Canoeing and Rafting

Migration l Fish Ladders

Spawning l Mokelumne River Fish Hatchery –Built by EBMUD as part of water rights deal –approx. 4 million Salmon and Steelhead Trout per year

Wildlife Habitat l Grazing l Hunting

Power Generation l East Bay Municipal Utilities District –Hydroelectric Power - 40 million KW- hour/year –Enough to meet needs of 10,400 people

Pollution Sources l EPA Index of Watershed Indicators –Rank 4: Less serious water quality problems - High vulnerability to stressors such as pollutant loadings l Point Source l Non-Point Source

Point Sources l No CERCLA Sites l Gravel Mining –2 major dredge tailing areas w/many gravel pits l Industrial Waste Ponds –4 main areas l Sewage Waste Ponds –2 locations l Lodi Treatment Plant (4 discharge points)

Non-Point Source l Agriculture –Fertilizers –Pesticides l Farming –Grazing animals l City of Lodi (Storm sewers?) l Boating (New Hope Landing)

Potential Pollution Management Strategies l Excavate Dredge Tailings l Grazing Control l Limit boating activities l Limit pesticide/fertilizer use l ?????