Mission

MISSION CREEK· Lake, Montana· Built 1935· Earth·
High Hazard Irrigation Recreation Federal Government

Key Takeaway

Mission is classified as high hazard in Montana. It was completed in 1935 and is 91 years old. Its primary use is irrigation. 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 Length1,848 ft
Dam TypeEarth
Normal Storage7.0K acre-ft
Year Completed1935 (91 years old)
NID IDMT00589

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, 2011
State Regulated: No

Ownership

BIA

Federal Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Mission?

Mission 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 Mission?

Mission is owned by BIA (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Mission built?

Mission was completed in 1935, making it 91 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 Mission?

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

When was Mission last inspected?

Mission was last inspected on July 21, 2011. 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.