Calaveras Reservoir is located primarily in Santa Clara County, California, with a small portion and its dam in Alameda County, California. In Spanish, Calaveras means "skulls".
The reservoir is fed mainly by Arroyo Hondo and Calaveras Creek. Lying in the Calaveras Valley, the region is geologically active with the Calaveras Fault parallel to and to the west of the dam site. The seismic hazard forced replacement of the original dam. The replacement dam began construction in 2011 and was completed in 2019.
The Calaveras Valley has diverse wildlife including deer, coyotes, squirrels, turkey vultures, red-winged blackbirds, yellow-billed magpies, red-tailed hawks, brewer's blackbirds, purple martins, barn swallows, bullock's orioles, and warblers. Since at least 2008, a pair of bald eagles has nested regularly.
Address 95035, United States
Coordinates 37°28'14.359" N -121°49'2.056" E