Built in 1963 by the Bureau of Reclamation, this Earth-type dam stands at a height of 73 feet, with a structural height of 91 feet and a length of 745 feet. It serves a primary purpose of water supply, providing a storage capacity of 14,660 acre-feet and covering a surface area of 750 acres.
With a high hazard potential and a moderate risk assessment rating, Lewiston Dam plays a crucial role in managing water resources in the region. Despite not being state-regulated, the Bureau of Reclamation oversees its operations, inspections, and regulatory aspects. The dam's uncontrolled spillway, with a width of 66 feet, further underscores its importance for flood protection and water management in the area. Overall, Lewiston Dam stands as a significant infrastructure for water resource enthusiasts and climate advocates to monitor and study in Trinity County.
Year Completed |
1963 |
Dam Length |
745 |
Dam Height |
73 |
River Or Stream |
TRINITY RIVER |
Primary Dam Type |
Earth |
Surface Area |
750 |
Hydraulic Height |
73 |
Drainage Area |
719 |
Nid Storage |
14660 |
Structural Height |
91 |
Hazard Potential |
High |
Nid Height |
91 |
| Location | Reservations | Toilets |
|---|---|---|
Mary Smith Campground
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Mary Smith
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Cooper Gulch Campground
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Cooper Gulch
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Tunnel Rock Campground
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Tunnel Rock
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