Rivermill Mascoma Hydro Dam
Key Takeaway
Rivermill Mascoma Hydro Dam is classified as high hazard in New Hampshire. It was completed in 1920 and is 106 years old. Its primary use is hydroelectric. 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 | 22 ft (taller than 76.5% in NH) |
| Dam Length | 300 ft |
| Dam Type | Concrete |
| Max Storage | 210 acre-ft |
| Normal Storage | 170 acre-ft |
| Surface Area | 8 acres |
| Drainage Area | 188 sq mi |
| Year Completed | 1920 (106 years old) |
| Year Modified | 1925 |
| NID ID | NH00155 |
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
RIVERMILL HYDROELECTRIC INC
Private
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High Hazard 33 ftFrequently Asked Questions
What is the hazard classification of Rivermill Mascoma Hydro Dam?
Rivermill Mascoma Hydro 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 Rivermill Mascoma Hydro Dam?
Rivermill Mascoma Hydro Dam is owned by RIVERMILL HYDROELECTRIC INC (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Rivermill Mascoma Hydro Dam built?
Rivermill Mascoma Hydro Dam was completed in 1920, making it 106 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 Rivermill Mascoma Hydro Dam?
Rivermill Mascoma Hydro Dam serves the following purposes: Hydroelectric. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Rivermill Mascoma Hydro Dam?
Rivermill Mascoma Hydro Dam has a dam height of 22 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 Rivermill Mascoma Hydro Dam last inspected?
Rivermill Mascoma Hydro Dam was last inspected on August 8, 2018. Inspection dates indicate when a formal review occurred, not the results of that inspection.