John W. Flannagan Dam
Key Takeaway
John W. Flannagan Dam is classified as high hazard in Virginia. It was completed in 1963 and is 63 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 Length | 916 ft |
| Dam Type | Rockfill |
| Max Storage | 145.7K acre-ft |
| Normal Storage | 67.1K acre-ft |
| Surface Area | 1,143 acres |
| Drainage Area | 221 sq mi |
| Max Discharge | 246,700 cfs |
| Year Completed | 1963 (63 years old) |
| NID ID | VA051001 |
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 - Huntington District
Federal Government
Nearby Dams
Frequently Asked Questions
What is the hazard classification of John W. Flannagan Dam?
John W. Flannagan 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 John W. Flannagan Dam?
John W. Flannagan Dam is owned by USACE - Huntington District (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was John W. Flannagan Dam built?
John W. Flannagan Dam was completed in 1963, making it 63 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 John W. Flannagan Dam?
John W. Flannagan Dam serves the following purposes: Flood Risk Reduction, Other, Fish And Wildlife Pond, Recreation, Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
When was John W. Flannagan Dam last inspected?
John W. Flannagan Dam was last inspected on September 2, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.