Rock Creek Lake

ROCK CREEK· Powell, Montana· Built 1960· Earth· 30 ft tall
Significant Hazard Water Supply Private

Key Takeaway

Rock Creek Lake is classified as significant hazard in Montana. It was completed in 1960 and is 66 years old. Its primary use is water supply. Significant hazard means failure could cause economic or environmental damage. Learn more.

Physical Details

Dam Height 30 ft (taller than 82.7% in MT)
Dam Length320 ft
Dam TypeEarth
Max Storage2.6K acre-ft
Normal Storage1.5K acre-ft
Year Completed1960 (66 years old)
NID IDMT03747

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: No
State Regulated: Yes
Regulatory Agency: DNRC

Ownership

FRANKLIN INC

Private

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Rock Creek Lake?

Rock Creek Lake 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 Rock Creek Lake?

Rock Creek Lake is owned by FRANKLIN INC (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Rock Creek Lake built?

Rock Creek Lake was completed in 1960, making it 66 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 Rock Creek Lake?

Rock Creek Lake serves the following purposes: Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Rock Creek Lake?

Rock Creek Lake has a dam height of 30 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.