Tomhannock Reservoir Dam
Key Takeaway
Tomhannock Reservoir Dam is classified as high hazard in New York. It was completed in 1905 and is 121 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 | 68 ft (taller than 96.1% in NY) |
| Dam Length | 700 ft |
| Dam Type | Earth |
| Max Storage | 56.6K acre-ft |
| Normal Storage | 39.5K acre-ft |
| Surface Area | 1,742 acres |
| Drainage Area | 67 sq mi |
| Year Completed | 1905 (121 years old) |
| NID ID | NY00117 |
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
CITY OF TROY
Local Government
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Significant Hazard 19 ftFrequently Asked Questions
What is the hazard classification of Tomhannock Reservoir Dam?
Tomhannock Reservoir 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 Tomhannock Reservoir Dam?
Tomhannock Reservoir Dam is owned by CITY OF TROY (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Tomhannock Reservoir Dam built?
Tomhannock Reservoir Dam was completed in 1905, making it 121 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 Tomhannock Reservoir Dam?
Tomhannock Reservoir Dam serves the following purposes: Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Tomhannock Reservoir Dam?
Tomhannock Reservoir Dam has a dam height of 68 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 Tomhannock Reservoir Dam last inspected?
Tomhannock Reservoir Dam was last inspected on January 5, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.