Mokelumne River

River in east-central California; length 225 km/140 mi. The Mokelumne River flows from the Sierra Nevada to the San Joaquin River. On its course, the Pardee Reservoir (impounded 1929), 40 km/25 mi east-northeast of the city of Lodi, is an important source of water for cities in the eastern San Francisco Bay area.

The North Fork of the Mokelumne River, its longest headstream, rises in the Sierra Nevada near Ebbets Pass, in Alpine County, and flows mainly southwest to Lodi, then to the San Joaquin River, 32 km/20 mi northwest of Stockton. The river is dammed at several points for power generation. In the 1850s–70s, when gold prospecting was widespread in this area, on the Mother Lode, the hamlet of Mokelumne Hill, 11 km/7 mi east-northeast of the Pardee Reservoir, was notorious for its lawlessness.