Lake Twotowns Dam

TR MOHAWK RIVER· Coos, New Hampshire· Built 1936· Earth· 25 ft tall
Low Hazard Recreation Private

Key Takeaway

Lake Twotowns Dam is classified as low hazard in New Hampshire. It was completed in 1936 and is 90 years old. Its primary use is recreation.

Physical Details

Dam Height 25 ft (taller than 80.2% in NH)
Dam Length700 ft
Dam TypeEarth
Max Storage51 acre-ft
Normal Storage15 acre-ft
Surface Area3 acres
Drainage Area0 sq mi
Max Discharge55 cfs
Year Completed1936 (90 years old)
Year Modified1997
NID IDNH00172

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

NORTH COUNTRY COOS

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Lake Twotowns Dam?

Lake Twotowns 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 Lake Twotowns Dam?

Lake Twotowns Dam is owned by NORTH COUNTRY COOS (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Lake Twotowns Dam built?

Lake Twotowns Dam was completed in 1936, making it 90 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 Lake Twotowns Dam?

Lake Twotowns 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 Lake Twotowns Dam?

Lake Twotowns Dam 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 Lake Twotowns Dam last inspected?

Lake Twotowns 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.