Plymouth Reservoir Dam
Key Takeaway
Plymouth Reservoir Dam is classified as high hazard in Connecticut. It was completed in 1881 and is 145 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 | 20 ft (taller than 72.5% in CT) |
| Dam Length | 730 ft |
| Dam Type | Earth |
| Max Storage | 390 acre-ft |
| Normal Storage | 290 acre-ft |
| Surface Area | 37 acres |
| Drainage Area | 1 sq mi |
| Max Discharge | 408 cfs |
| Year Completed | 1881 (145 years old) |
| NID ID | CT00286 |
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
Town of Plymouth
Local Government
Nearby Dams
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Significant Hazard 6 ftFrequently Asked Questions
What is the hazard classification of Plymouth Reservoir Dam?
Plymouth 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 Plymouth Reservoir Dam?
Plymouth Reservoir Dam is owned by Town of Plymouth (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Plymouth Reservoir Dam built?
Plymouth Reservoir Dam was completed in 1881, making it 145 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 Plymouth Reservoir Dam?
Plymouth 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 Plymouth Reservoir Dam?
Plymouth Reservoir Dam has a dam height of 20 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 Plymouth Reservoir Dam last inspected?
Plymouth Reservoir Dam was last inspected on May 31, 2018. Inspection dates indicate when a formal review occurred, not the results of that inspection.