Br-12 Retention Dam

FIFTEENMILE CK./MILK RIVER· Blaine, Montana· Built 1936· Gravity·
High Hazard Flood Risk Reduction Federal Government

Key Takeaway

Br-12 Retention Dam is classified as high hazard in Montana. It was completed in 1936 and is 90 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 Length852 ft
Dam TypeGravity
Max Storage322 acre-ft
Normal Storage0 acre-ft
Surface Area108 acres
Drainage Area27 sq mi
Max Discharge6,350 cfs
Year Completed1936 (90 years old)
NID IDMT00041

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: July 21, 2020
State Regulated: No

Ownership

DOI BLM

Federal Government

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Frequently Asked Questions

What is the hazard classification of Br-12 Retention Dam?

Br-12 Retention 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 Br-12 Retention Dam?

Br-12 Retention Dam is owned by DOI BLM (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Br-12 Retention Dam built?

Br-12 Retention 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 Br-12 Retention Dam?

Br-12 Retention 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.

When was Br-12 Retention Dam last inspected?

Br-12 Retention Dam was last inspected on July 21, 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.