Twin Lake
Key Takeaway
Twin Lake is classified as low hazard in California. It was completed in 1903 and is 123 years old. Its primary use is hydroelectric.
Physical Details
| Dam Height | 22 ft (taller than 18.8% in CA) |
| Dam Length | 1,520 ft |
| Dam Type | Earth |
| Max Storage | 21.6K acre-ft |
| Normal Storage | 1.2K acre-ft |
| Surface Area | 600 acres |
| Drainage Area | 14 sq mi |
| Max Discharge | 12,400 cfs |
| Year Completed | 1903 (123 years old) |
| NID ID | CA00384 |
Safety Information
No probable loss of human life and low economic/environmental losses expected.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
Pacific Gas and Electric Company
Private
Nearby Dams
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Low Hazard 38 ftFrequently Asked Questions
What is the hazard classification of Twin Lake?
Twin Lake is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Twin Lake?
Twin Lake is owned by Pacific Gas and Electric Company (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Twin Lake built?
Twin Lake was completed in 1903, making it 123 years old. Many U.S. dams were built between the 1930s and 1970s during a period of major infrastructure investment.
What is the primary purpose of Twin Lake?
Twin Lake serves the following purposes: Hydroelectric. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Twin Lake?
Twin Lake has a dam height of 22 ft. Dam height is measured from the natural streambed at the downstream toe to the top of the dam, and may differ from the visible height.
When was Twin Lake last inspected?
Twin Lake was last inspected on September 7, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.