Castle Rock Saddle Dam

TR-EAST FORK ARMELLS CREEK· Rosebud, Montana· Built 1976· Earth· 20 ft tall
High Hazard Other Public Utility

Key Takeaway

Castle Rock Saddle Dam is classified as high hazard in Montana. It was completed in 1976 and is 50 years old. Its primary use is other. 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 Height 20 ft (taller than 44.5% in MT)
Dam Length800 ft
Dam TypeEarth
Max Storage2.3K acre-ft
Normal Storage1.8K acre-ft
Surface Area140 acres
Drainage Area1 sq mi
Max Discharge2,820 cfs
Year Completed1976 (50 years old)
NID IDMT03146

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 15, 2014
State Regulated: Yes
Regulatory Agency: DEQ

Ownership

TALEN ENERGY

Public Utility

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Castle Rock Saddle Dam?

Castle Rock Saddle 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 Castle Rock Saddle Dam?

Castle Rock Saddle Dam is owned by TALEN ENERGY (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Castle Rock Saddle Dam built?

Castle Rock Saddle Dam was completed in 1976, making it 50 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 Castle Rock Saddle Dam?

Castle Rock Saddle Dam serves the following purposes: Other. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Castle Rock Saddle Dam?

Castle Rock Saddle Dam has a dam height of 20 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.

When was Castle Rock Saddle Dam last inspected?

Castle Rock Saddle Dam was last inspected on July 15, 2014. 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.