Banning Dam

Banning Dam
Lake Eleanor Dam
Lake Eleanor as seen from above
Location of Banning Dam
Lake Eleanor Dam in California
CountryUnited States
LocationVentura County, California
Coordinates34°08′07″N 118°51′06″W / 34.13528°N 118.85167°W / 34.13528; -118.85167
StatusOperational
Construction began1881 (1881)
Opening date1889 (1889)
Construction cost$500 (1889)
Owner(s)Conejo Open Space Conservation Agency
Dam and spillways
Type of damArch, constant-radius
Height37 ft (11 m)
Length140 ft (43 m)
Reservoir
CreatesLake Eleanor

Lake Eleanor (National ID # CA00737), also known as Banning Dam, is an 8-acre (3.2 ha) freshwater lake (gravity dam) near Westlake Village in Thousand Oaks, California. The lake lies within the 513-acre (208 ha) Lake Eleanor Open Space and was Ventura County Historic Landmark No. 120 in 1988. It is also designated City of Thousand Oaks Historical Landmark No. 9. Under ownership of Conejo Open Space Conservation Agency (COSCA), the lake sits in a gorge with sheer cliffs and drops of 40–50 ft (12–15 m). An artificial lake, it was first constructed in 1889, and may be the first concrete arched dam built in California.

Although not a major dam, Banning Dam is among the oldest still standing in the state. Nearby Sherwood Dam dates from 1904. It is less than 1 mile (1.6 km) east of Lake Sherwood. The structure is located within the Lake Eleanor Open Space. At 37 feet high, and 140 feet long at its crest, the dam is owned by the local Conejo Open Space Conservation Agency.