Coordinates: 37°35′18″N 121°38′52″W / 37.58833°N 121.64778°W / 37.58833; -121.64778
Mendenhall Springs is an unincorporated community in Alameda County, California. It is located 9 miles (14 km) southeast of Livermore, at an elevation of 1818 feet (554 m).
William M. Mendenhall established a health spa here in the 1870s, which by 1909 had accommodations for 75 people, from springs that had been diverted through tunnels originally bored for gold prospecting.
This region experiences warm (but not hot) and dry summers, with no average monthly temperatures above 71.6 °F. According to the Köppen Climate Classification system, Mendenhall Springs has a warm-summer Mediterranean climate, abbreviated "Csb" on climate maps.