Long Hill Reservoir Dam
Key Takeaway
Long Hill Reservoir Dam is classified as high hazard in Connecticut. It was completed in 1914 and is 112 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 | 80 ft (taller than 98.3% in CT) |
| Dam Length | 890 ft |
| Dam Type | Earth |
| Max Storage | 2.1K acre-ft |
| Normal Storage | 2.1K acre-ft |
| Surface Area | 87 acres |
| Drainage Area | 3 sq mi |
| Max Discharge | 2,130 cfs |
| Year Completed | 1914 (112 years old) |
| Year Modified | 1993 |
| NID ID | CT00307 |
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
Connecticut Water Company
Public Utility
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What is the hazard classification of Long Hill Reservoir Dam?
Long Hill 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 Long Hill Reservoir Dam?
Long Hill Reservoir Dam is owned by Connecticut Water Company (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Long Hill Reservoir Dam built?
Long Hill Reservoir Dam was completed in 1914, making it 112 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 Long Hill Reservoir Dam?
Long Hill 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 Long Hill Reservoir Dam?
Long Hill Reservoir Dam has a dam height of 80 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 Long Hill Reservoir Dam last inspected?
Long Hill Reservoir Dam was last inspected on November 13, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.