Allegheny River Lock and Dam 9
Key Takeaway
Allegheny River Lock and Dam 9 is classified as low hazard in Pennsylvania. It was completed in 1938 and is 88 years old. Its primary use is navigation.
Physical Details
| Dam Length | 1,040 ft |
| Dam Type | Gravity |
| Max Storage | 13.5K acre-ft |
| Normal Storage | 13.5K acre-ft |
| Surface Area | 1,040 acres |
| Drainage Area | 8,401 sq mi |
| Max Discharge | 125,000 cfs |
| Year Completed | 1938 (88 years old) |
| NID ID | PA00119 |
Safety Information
No probable loss of human life and low economic/environmental losses expected.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
USACE - Pittsburgh District
Federal Government
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High Hazard 27 ftFrequently Asked Questions
What is the hazard classification of Allegheny River Lock and Dam 9?
Allegheny River Lock and Dam 9 is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Allegheny River Lock and Dam 9?
Allegheny River Lock and Dam 9 is owned by USACE - Pittsburgh District (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Allegheny River Lock and Dam 9 built?
Allegheny River Lock and Dam 9 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 Allegheny River Lock and Dam 9?
Allegheny River Lock and Dam 9 serves the following purposes: Navigation, Hydroelectric. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
When was Allegheny River Lock and Dam 9 last inspected?
Allegheny River Lock and Dam 9 was last inspected on October 16, 2019. Inspection dates indicate when a formal review occurred, not the results of that inspection.