Mansfield Hollow Dam
Key Takeaway
Mansfield Hollow Dam is classified as high hazard in Connecticut. It was completed in 1952 and is 74 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 Height | 78 ft (taller than 98.2% in CT) |
| Dam Length | 14,050 ft |
| Dam Type | Gravity |
| Max Storage | 76.0K acre-ft |
| Normal Storage | 2.8K acre-ft |
| Surface Area | 450 acres |
| Drainage Area | 159 sq mi |
| Max Discharge | 106,500 cfs |
| Year Completed | 1952 (74 years old) |
| NID ID | CT00503 |
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 - New England District
Federal Government
Nearby Dams
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Significant Hazard 8 ftMansfield Recreation Pond
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Significant Hazard 21 ftBibbins Pond Dam
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Significant Hazard 9 ftHanks Hill Pond Dam
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Significant Hazard 9 ftLake Marie Dam
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Significant Hazard 9 ftVarga Pond
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Significant Hazard 4 ftFrequently Asked Questions
What is the hazard classification of Mansfield Hollow Dam?
Mansfield Hollow 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 Mansfield Hollow Dam?
Mansfield Hollow Dam is owned by USACE - New England District (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Mansfield Hollow Dam built?
Mansfield Hollow Dam was completed in 1952, making it 74 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 Mansfield Hollow Dam?
Mansfield Hollow Dam serves the following purposes: Flood Risk Reduction. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Mansfield Hollow Dam?
Mansfield Hollow Dam has a dam height of 78 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 Mansfield Hollow Dam last inspected?
Mansfield Hollow Dam was last inspected on June 1, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.