California's Major Man-Made Lakes: Reservoirs That Power the State

California's 1,400+ reservoirs capture Sierra Nevada snowmelt, enabling the nation's most productive agriculture and largest urban concentrations. Here are the key man-made lakes by region.

Northern California (Sacramento/Feather/American Systems)

• Lake Shasta (Shasta Lake) – Largest CA reservoir by volume (4.55 MAF*). Shasta Dam (1945) on Sacramento R. Hydro, flood control, recreation.
• Lake Oroville – 2nd largest (3.5 MAF). Oroville Dam (1968) on Feather R. Tallest US dam (770 ft). 2017 spillway crisis.
• Folsom Lake – Folsom Dam (1955) on American R. Critical for Sacramento flood protection & water supply.
• Trinity Lake – Trinity Dam (1962) on Trinity R. Part of Central Valley Project (CVP).
• Whiskeytown Lake – Whiskeytown Dam (1963) on Clear Creek. Recreation-focused (NPS).
• San Luis Reservoir – Off-stream (Pacheco Pass). CVP/SWP joint storage (2 MAF). Pumping plant lifts water 300 ft.

Central California (San Joaquin Valley Rim)

• Millerton Lake – Friant Dam (1949) on San Joaquin R. Friant-Kern & Madera Canals.
• Pine Flat Lake – Pine Flat Dam (1954) on Kings R. Flood control + irrigation.
• Lake Kaweah – Terminus Dam (1962) on Kaweah R. Small (185 KAF) but critical for Tulare Basin.
• Lake Success – Success Dam (1961) on Tule R.
• Isabella Lake – Isabella Dam (1953) on Kern R. Dam safety issues (seismic).

Southern California (Colorado River & Local Systems)

• Lake Mead – Hoover Dam (1935) on Colorado R. Largest US reservoir (26 MAF). AZ/NV border. Supplies SoCal via MWD.
• Lake Powell – Glen Canyon Dam (1963) on Colorado R. 2nd largest US (24 MAF). AZ/UT border. "Bathtub ring" icon of drought.
• Lake Havasu – Parker Dam (1938). Colorado River Aqueduct intake (MWD). London Bridge relocated here.
• Diamond Valley Lake – MWD off-stream (2000). 810 KAF. Emergency storage for SoCal.
• Salton Sea – Accidental (1905–07) Colorado R. breach. Inland saline lake. Ecological crisis (salinity, selenium, dust).
• Pyramid Lake / Castaic Lake – State Water Project (SWP) terminal reservoirs (LA Basin).

*MAF = Million Acre-Feet (1 MAF = 1.233 km³)

System Integration

CVP (federal) + SWP (state) + Colorado River Aqueduct + LA Aqueduct + Mokelumne/Hetch Hetchy = plumbed California. Climate change, SGMA (groundwater law), and ecosystem needs now drive reoperation.