Lake Gregory
Key Takeaway
Lake Gregory is classified as high hazard in California. It was completed in 1938 and is 88 years old. Its primary use is water supply. 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 | 90 ft (taller than 79.3% in CA) |
| Dam Length | 475 ft |
| Dam Type | Earth |
| Max Storage | 2.1K acre-ft |
| Surface Area | 88 acres |
| Drainage Area | 3 sq mi |
| Year Completed | 1938 (88 years old) |
| NID ID | CA00224 |
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
San Bernardino County Regional Parks
Local Government
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What is the hazard classification of Lake Gregory?
Lake Gregory 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 Lake Gregory?
Lake Gregory is owned by San Bernardino County Regional Parks (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Lake Gregory built?
Lake Gregory was completed in 1938, making it 88 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 Lake Gregory?
Lake Gregory serves the following purposes: Water Supply, Irrigation, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Lake Gregory?
Lake Gregory has a dam height of 90 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 Lake Gregory last inspected?
Lake Gregory was last inspected on May 25, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.