Frenchman Dam

FRENCHMAN CREEK· Phillips, Montana· Built 1953· Earth· 63 ft tall
Significant Hazard Irrigation State Government

Key Takeaway

Frenchman Dam is classified as significant hazard in Montana. It was completed in 1953 and is 73 years old. Its primary use is irrigation. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 63 ft (taller than 98% in MT)
Dam Length2,100 ft
Dam TypeEarth
Max Storage13.5K acre-ft
Normal Storage3.8K acre-ft
Surface Area800 acres
Drainage Area2,460 sq mi
Max Discharge36,000 cfs
Year Completed1953 (73 years old)
NID IDMT00003

Safety Information

Significant Hazard

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?

Emergency Action Plan: Yes
Last Inspection: October 17, 2022
State Regulated: Yes
Regulatory Agency: DNRC

Ownership

STATE WATER PROJECTS

State Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Frenchman Dam?

Frenchman Dam 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 Frenchman Dam?

Frenchman Dam is owned by STATE WATER PROJECTS (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Frenchman Dam built?

Frenchman Dam was completed in 1953, making it 73 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 Frenchman Dam?

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

How tall is Frenchman Dam?

Frenchman Dam has a dam height of 63 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 Frenchman Dam last inspected?

Frenchman Dam was last inspected on October 17, 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.