| Los Vaqueros Reservoir | |
|---|---|
 Aerial view from the southeast | |
  Los Vaqueros Reservoir  Los Vaqueros Reservoir | |
| Location | Diablo Range, Contra Costa County, California |
| Coordinates | 37°49′13″N 121°44′02″W / 37.82025°N 121.7338°W |
| Type | reservoir |
| Basin countries | United States |
| Max. length | 2.5 mi (4.0 km) |
| Max. width | 2.5 mi (4.0 km) |
| Surface area | 1,400 acres (570 ha) |
| Average depth | 170 ft (52 m) |
| Max. depth | 170 ft (52 m) |
| Water volume | 160,000 acre⋅ft (0.20 km3) |
| Surface elevation | 524 ft (160 m)[1] |
| Settlements | Brentwood, Livermore |
The Los Vaqueros Reservoir and watershed is located in the northern Diablo Range, within northeastern Contra Costa County, northern California. It was completed by the Contra Costa Water District (CCWD) in 1998 to improve the quality of drinking water for its 550,000 customers in Central and Eastern Contra Costa County. The reservoir is accessible via Vasco Road, a road which connects Brentwood and Livermore.
Some 20,000 acres of land was acquired to provide for construction of the dam and its 1500-acre reservoir, as well as protection of 19,300 acres of associated watershed.