Ellsworth
Key Takeaway
Ellsworth is classified as high hazard in Maine. It was completed in 1907 and is 119 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 | 62 ft (taller than 97.8% in ME) |
| Dam Length | 377 ft |
| Dam Type | Concrete |
| Max Storage | 2.5K acre-ft |
| Normal Storage | 2.5K acre-ft |
| Surface Area | 125 acres |
| Drainage Area | 613 sq mi |
| Max Discharge | 17,000 cfs |
| Year Completed | 1907 (119 years old) |
| NID ID | ME00263 |
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
Black Bear Hydro Partners, LLC
Private
Nearby Dams
Graham Lake Dam
Hancock, ME
High Hazard 43 ftGraham Lake Flood Control
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Low Hazard 8 ftFosters Pond
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Low Hazard 16 ftPatten Brook
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Low Hazard 9 ftBeech Hill Pond
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Low Hazard 11 ftFrequently Asked Questions
What is the hazard classification of Ellsworth?
Ellsworth 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 Ellsworth?
Ellsworth is owned by Black Bear Hydro Partners, LLC (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Ellsworth built?
Ellsworth was completed in 1907, making it 119 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 Ellsworth?
Ellsworth serves the following purposes: Hydroelectric, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Ellsworth?
Ellsworth has a dam height of 62 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 Ellsworth last inspected?
Ellsworth was last inspected on September 21, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.