Errol

Androscoggin River· Coos, New Hampshire· Built 1887· Other· 25 ft tall
Low Hazard Hydroelectric Not Listed

Key Takeaway

Errol is classified as low hazard in New Hampshire. It was completed in 1887 and is 139 years old. Its primary use is hydroelectric.

Physical Details

Dam Height 25 ft (taller than 80.2% in NH)
Dam Length205 ft
Dam TypeOther
Max Storage80.0K acre-ft
Normal Storage80.0K acre-ft
Surface Area7,850 acres
Drainage Area1,045 sq mi
Max Discharge19,700 cfs
Year Completed1887 (139 years old)
NID IDNH00161

Safety Information

Low Hazard

No probable loss of human life and low economic/environmental losses expected.

Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?

Emergency Action Plan: No
Last Inspection: August 7, 2018
State Regulated: Yes
Regulatory Agency: NHDES DAM BUREAU

Ownership

Not Listed

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Errol?

Errol is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Errol?

Errol is owned by information not available (Not Listed). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Errol built?

Errol was completed in 1887, making it 139 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 Errol?

Errol 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 Errol?

Errol has a dam height of 25 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 Errol last inspected?

Errol was last inspected on August 7, 2018. Inspection dates indicate when a formal review occurred, not the results of that inspection.

Data from the National Inventory of Dams (NID) maintained by the US Army Corps of Engineers. Dam conditions may have changed since the last update. This site is not affiliated with USACE. Do not use for emergency planning — contact your local dam safety program.