Upper Occoquan Dam
Key Takeaway
Upper Occoquan 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 | 65 ft (taller than 96.4% in VA) |
| Dam Length | 802 ft |
| Dam Type | Gravity |
| Max Storage | 25.5K acre-ft |
| Normal Storage | 25.5K acre-ft |
| Surface Area | 1,840 acres |
| Drainage Area | 595 sq mi |
| NID ID | VA153004 |
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
Public Utility
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What is the hazard classification of Upper Occoquan Dam?
Upper Occoquan 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 Upper Occoquan Dam?
Upper Occoquan Dam is owned by Fairfax County Water Authority (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
What is the primary purpose of Upper Occoquan Dam?
Upper Occoquan 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 Upper Occoquan Dam?
Upper Occoquan Dam has a dam height of 65 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 Upper Occoquan Dam last inspected?
Upper Occoquan Dam was last inspected on November 5, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.