Souhegan River Site 25b Dam

TEMPLE BROOK· Hillsborough, New Hampshire· Built 1967· Earth· 74 ft tall
High Hazard Flood Risk Reduction State Government

Key Takeaway

Souhegan River Site 25b Dam is classified as high hazard in New Hampshire. It was completed in 1967 and is 59 years old. Its primary use is flood risk reduction. 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 74 ft (taller than 98% in NH)
Dam Length695 ft
Dam TypeEarth
Max Storage1.6K acre-ft
Normal Storage38 acre-ft
Surface Area6 acres
Drainage Area6 sq mi
Max Discharge15,800 cfs
Year Completed1967 (59 years old)
NID IDNH00476

Safety Information

High Hazard

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?

Emergency Action Plan: Yes
Last Inspection: October 11, 2022
State Regulated: Yes
Regulatory Agency: NH DES

Ownership

NH DES WATER DIVISION

State Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Souhegan River Site 25b Dam?

Souhegan River Site 25b Dam 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 Souhegan River Site 25b Dam?

Souhegan River Site 25b Dam is owned by NH DES WATER DIVISION (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Souhegan River Site 25b Dam built?

Souhegan River Site 25b Dam was completed in 1967, making it 59 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 Souhegan River Site 25b Dam?

Souhegan River Site 25b Dam serves the following purposes: Flood Risk Reduction. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Souhegan River Site 25b Dam?

Souhegan River Site 25b Dam has a dam height of 74 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 Souhegan River Site 25b Dam last inspected?

Souhegan River Site 25b Dam was last inspected on October 11, 2022. 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.