Donley Reservoir (Rosebud)

LARSON COULEE· Rosebud, Montana· Built 1930· Earth· 38 ft tall

Key Takeaway

Donley Reservoir (Rosebud) is classified as low hazard in Montana. It was completed in 1930 and is 96 years old. Its primary use is fire protection.

Physical Details

Dam Height 38 ft (taller than 94.3% in MT)
Dam Length400 ft
Dam TypeEarth
Max Storage654 acre-ft
Normal Storage391 acre-ft
Drainage Area4 sq mi
Max Discharge3,500 cfs
Year Completed1930 (96 years old)
NID IDMT00066

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
State Regulated: Yes
Regulatory Agency: DNRC

Ownership

JOE DONLEY

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Donley Reservoir (Rosebud)?

Donley Reservoir (Rosebud) 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 Donley Reservoir (Rosebud)?

Donley Reservoir (Rosebud) is owned by JOE DONLEY (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Donley Reservoir (Rosebud) built?

Donley Reservoir (Rosebud) was completed in 1930, making it 96 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 Donley Reservoir (Rosebud)?

Donley Reservoir (Rosebud) 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.

How tall is Donley Reservoir (Rosebud)?

Donley Reservoir (Rosebud) has a dam height of 38 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.

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.