Isabella Dam
Key Takeaway
Isabella Dam is classified as high hazard in California. It was completed in 1953 and is 73 years old. Its primary use is flood risk reduction. 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 | 98 ft (taller than 81.7% in CA) |
| Dam Length | 1,695 ft |
| Dam Type | Earth |
| Max Storage | 1.2M acre-ft |
| Normal Storage | 568.0K acre-ft |
| Surface Area | 11,200 acres |
| Drainage Area | 2,074 sq mi |
| Max Discharge | 53,000 cfs |
| Year Completed | 1953 (73 years old) |
| NID ID | CA10106 |
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
USACE - Sacramento District
Federal Government
Frequently Asked Questions
What is the hazard classification of Isabella Dam?
Isabella Dam 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 Isabella Dam?
Isabella Dam is owned by USACE - Sacramento District (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Isabella Dam built?
Isabella Dam was completed in 1953, making it 73 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 Isabella Dam?
Isabella Dam serves the following purposes: Flood Risk Reduction, Irrigation, Recreation, Hydroelectric. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Isabella Dam?
Isabella Dam has a dam height of 98 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 Isabella Dam last inspected?
Isabella Dam was last inspected on October 1, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.