Mianus Filter Plant Dam
Key Takeaway
Mianus Filter Plant Dam is classified as high hazard in Connecticut. It was completed in 1875 and is 151 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 | 31 ft (taller than 89.2% in CT) |
| Dam Length | 130 ft |
| Dam Type | Masonry |
| Max Storage | 118 acre-ft |
| Normal Storage | 101 acre-ft |
| Surface Area | 7 acres |
| Drainage Area | 30 sq mi |
| Max Discharge | 680 cfs |
| Year Completed | 1875 (151 years old) |
| NID ID | CT00040 |
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
Aquarion Water Company of Connecticut
Public Utility
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Significant Hazard 18 ftFrequently Asked Questions
What is the hazard classification of Mianus Filter Plant Dam?
Mianus Filter Plant 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 Mianus Filter Plant Dam?
Mianus Filter Plant Dam is owned by Aquarion Water Company of Connecticut (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Mianus Filter Plant Dam built?
Mianus Filter Plant Dam was completed in 1875, making it 151 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 Mianus Filter Plant Dam?
Mianus Filter Plant 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 Mianus Filter Plant Dam?
Mianus Filter Plant Dam has a dam height of 31 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 Mianus Filter Plant Dam last inspected?
Mianus Filter Plant Dam was last inspected on August 27, 2020. Inspection dates indicate when a formal review occurred, not the results of that inspection.