Butt Valley
Key Takeaway
Butt Valley is classified as high hazard in California. It was completed in 1924 and is 102 years old. Its primary use is hydroelectric. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.
Physical Details
| Dam Height | 70 ft (taller than 72.8% in CA) |
| Dam Length | 1,520 ft |
| Dam Type | Earth |
| Max Storage | 49.9K acre-ft |
| Normal Storage | 49.8K acre-ft |
| Surface Area | 1,600 acres |
| Drainage Area | 84 sq mi |
| Max Discharge | 30,000 cfs |
| Year Completed | 1924 (102 years old) |
| NID ID | CA00326 |
Safety Information
Loss of human life is likely if the dam fails.
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
Frequently Asked Questions
What is the hazard classification of Butt Valley?
Butt Valley is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Butt Valley?
Butt Valley is owned by Pacific Gas and Electric Company (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Butt Valley built?
Butt Valley was completed in 1924, making it 102 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 Butt Valley?
Butt Valley 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 Butt Valley?
Butt Valley has a dam height of 70 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 Butt Valley last inspected?
Butt Valley was last inspected on September 15, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.