South Fork Detention Dam

CHERRY CK./YELLOWSTONE RIVER· Prairie, Montana· Built 1964· Gravity·
Low Hazard Fire Protection Stock Or Small Fish Pond Federal Government

Key Takeaway

South Fork Detention Dam is classified as low hazard in Montana. It was completed in 1964 and is 62 years old. Its primary use is fire protection.

Physical Details

Dam Length730 ft
Dam TypeGravity
Max Storage520 acre-ft
Surface Area41 acres
Year Completed1964 (62 years old)
NID IDMT00660

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: July 24, 2020
State Regulated: No

Ownership

DOI BLM

Federal Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of South Fork Detention Dam?

South Fork Detention 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 South Fork Detention Dam?

South Fork Detention Dam is owned by DOI BLM (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was South Fork Detention Dam built?

South Fork Detention Dam was completed in 1964, making it 62 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 South Fork Detention Dam?

South Fork Detention Dam serves the following purposes: Fire Protection, Stock, Or Small Fish Pond. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

When was South Fork Detention Dam last inspected?

South Fork Detention Dam was last inspected on July 24, 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.