Webster
Key Takeaway
Webster is classified as significant hazard in New Hampshire. It was completed in 1917 and is 109 years old. Its primary use is hydroelectric. Significant hazard means failure could cause economic or environmental damage. Learn more.
Physical Details
| Dam Height | 22 ft (taller than 76.5% in NH) |
| Dam Length | 250 ft |
| Dam Type | Concrete |
| Max Storage | 147 acre-ft |
| Normal Storage | 147 acre-ft |
| Surface Area | 15 acres |
| Drainage Area | 259 sq mi |
| Max Discharge | 11,010 cfs |
| Year Completed | 1917 (109 years old) |
| NID ID | NH00378 |
Safety Information
No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
Pembroke Hydro Associates
Private
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What is the hazard classification of Webster?
Webster is classified as Significant Hazard. No probable loss of human life, but can cause economic loss, environmental damage, or disruption of lifeline facilities. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Webster?
Webster is owned by Pembroke Hydro Associates (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Webster built?
Webster was completed in 1917, making it 109 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 Webster?
Webster 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 Webster?
Webster 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 Webster last inspected?
Webster was last inspected on May 25, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.