| Lewiston Dam | |
| Name Official: | Lewiston Dam |
| Dam Crosses: | Trinity River |
| Res Name: | Lewiston Lake |
| Location: | Trinity County, California, United States |
| Operator: | US Bureau of Reclamation |
| Dam Length: | 745feet |
| Dam Height: | 91feet |
| Res Capacity Total: | 14660acre.ft |
| Res Catchment: | 718sqmi |
| Res Surface: | 759acres |
| Coordinates: | 40.725°N -122.7961°W |
| Plant Capacity: | 350 KW |
| Plant Annual Gen: | 3,335,000 KWh |
Lewiston Dam is an earthfill dam on the Trinity River that forms Lewiston Lake near Weaverville, California, United States.[1] The 91feet high earthfill dam is 7miles downstream of Trinity Dam and was built by the U.S. Bureau of Reclamation.[1] Construction was completed in 1963.[2] Lewiston Lake and Dam are part of the Central Valley Project, which harnesses the waters from the Sacramento River and San Joaquin River watersheds to irrigate the Central Valley, and provide hydroelectricity.[1]