Lake Sonoma

Lake Sonoma is a reservoir west of Cloverdale in northern Sonoma County, California, created by the construction of Warm Springs Dam. Access from U.S. Route 101 is by way of Canyon Road (from the south) from Geyserville, or Dutcher Creek Road (from the north) from Cloverdale.

Lake Sonoma
The lake, just behind the Warm Springs Dam, which is to the right of this view
Location	Sonoma County, California
Coordinates	38°43′05″N 123°00′34″W
Lake type	reservoir
Primary inflows	Dry Creek
Primary outflows	Dry Creek[1]
Catchment area	130 sq mi (340 km2)[2]
Basin countries	United States
Max. length	5.7 mi (9 km)[1]
Surface area	2,700 acres (1,100 ha)[3]
Water volume	381,000 acre⋅ft (0.470 km3)[2]
Shore length1	50 miles (80 km)[3]
Surface elevation	200 feet (61 m)[1]
1 Shore length is not a well-defined measure.

The lake provides water for countywide growth and development, and for recreation. At full capacity, it has 50 miles (80 km) of shoreline, a surface area of more than 2,700 acres (11 km²),[3] and holds 381,000 acre feet (470,000,000 m³) of water.[2] Activities include boating, swimming, fishing, riding, hiking, camping, and hunting.[3] Notable features include the Milt Brandt Visitor Center, the adjacent Congressman Don Clausen Fish Hatchery, and the Warm Springs Recreation Area below the dam.

The US Army Corps of Engineers built Warm Springs Dam across Dry Creek. Completed in 1982, this rolled-earth embankment dam is 319 ft (97 m) high, 3,000 ft (900 m) long, and 30 ft (9 m) wide at the top. It contains 30,000,000 cu yd (23,000,000 m³) of earth.[2] The dam aids in flood control, and a hydroelectric plant produces electricity from the water released downstream. A minimum amount of flow must be maintained in Dry Creek to allow fish migration.

Pomo people had lived in the Dry Creek area since at least the 18th century, and some of them resisted the creation of the lake. Archaeologists at Sonoma State University have written about the prehistory and history of Warm Springs Dam, Lake Sonoma, and the Dry Creek Valley.[4]

Lake Sonoma

The California Office of Environmental Health Hazard Assessment (OEHHA) has developed a safe eating advisory for Lake Sonoma based on levels of mercury or PCBs found in fish caught from this water body.[5]