Contoocook Lake Dam

CONTOOCOOK RIVER· Cheshire, New Hampshire· Built 1885· Earth· 7 ft tall
Low Hazard Recreation Local Government

Key Takeaway

Contoocook Lake Dam is classified as low hazard in New Hampshire. It was completed in 1885 and is 141 years old. Its primary use is recreation.

Physical Details

Dam Height 7 ft (taller than 1.4% in NH)
Dam Length400 ft
Dam TypeEarth
Max Storage2.7K acre-ft
Normal Storage1.5K acre-ft
Surface Area443 acres
Drainage Area16 sq mi
Max Discharge1,256 cfs
Year Completed1885 (141 years old)
Year Modified1968
NID IDNH00098

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: October 28, 2020
State Regulated: Yes
Regulatory Agency: NH DES

Ownership

TOWN OF JAFFREY

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Contoocook Lake Dam?

Contoocook Lake Dam 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 Contoocook Lake Dam?

Contoocook Lake Dam is owned by TOWN OF JAFFREY (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Contoocook Lake Dam built?

Contoocook Lake Dam was completed in 1885, making it 141 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 Contoocook Lake Dam?

Contoocook Lake Dam serves the following purposes: Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Contoocook Lake Dam?

Contoocook Lake Dam has a dam height of 7 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 Contoocook Lake Dam last inspected?

Contoocook Lake Dam was last inspected on October 28, 2020. 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.