Occoquan Lower Storage Dam
Key Takeaway
Occoquan Lower Storage Dam is classified as high hazard in Virginia. 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 | 20 ft (taller than 26.8% in VA) |
| Dam Length | 484 ft |
| Dam Type | Gravity |
| Max Storage | 170 acre-ft |
| Normal Storage | 170 acre-ft |
| Surface Area | 19 acres |
| Drainage Area | 596 sq mi |
| NID ID | VA153005 |
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
Fairfax County Water Authority
Local Government
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What is the hazard classification of Occoquan Lower Storage Dam?
Occoquan Lower Storage 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 Occoquan Lower Storage Dam?
Occoquan Lower Storage Dam is owned by Fairfax County Water Authority (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
What is the primary purpose of Occoquan Lower Storage Dam?
Occoquan Lower Storage Dam serves the following purposes: Water Supply, Hydroelectric. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Occoquan Lower Storage Dam?
Occoquan Lower Storage Dam has a dam height of 20 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 Occoquan Lower Storage Dam last inspected?
Occoquan Lower Storage Dam was last inspected on November 5, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.