Hillside
Key Takeaway
Hillside is classified as high hazard in California. It was completed in 1910 and is 116 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 | 82 ft (taller than 77.1% in CA) |
| Dam Length | 645 ft |
| Dam Type | Rockfill |
| Max Storage | 12.9K acre-ft |
| Normal Storage | 12.9K acre-ft |
| Surface Area | 173 acres |
| Drainage Area | 13 sq mi |
| Max Discharge | 1,700 cfs |
| Year Completed | 1910 (116 years old) |
| NID ID | CA00446 |
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
Southern California Edison Company
Private
Nearby Dams
Frequently Asked Questions
What is the hazard classification of Hillside?
Hillside 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 Hillside?
Hillside is owned by Southern California Edison Company (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Hillside built?
Hillside was completed in 1910, making it 116 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 Hillside?
Hillside serves the following purposes: Hydroelectric, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Hillside?
Hillside has a dam height of 82 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 Hillside last inspected?
Hillside was last inspected on July 20, 2023. Inspection dates indicate when a formal review occurred, not the results of that inspection.