Castle Rock Reservoir Dam
Key Takeaway
Castle Rock Reservoir 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 | 67 ft (taller than 98.1% in MT) |
| Dam Length | 1,095 ft |
| Dam Type | Earth |
| Max Storage | 3.5K acre-ft |
| Normal Storage | 2.9K acre-ft |
| Surface Area | 140 acres |
| Drainage Area | 1 sq mi |
| Max Discharge | 2,820 cfs |
| Year Completed | 1976 (50 years old) |
| NID ID | MT01982 |
Safety Information
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?
Ownership
TALEN ENERGY
Public Utility
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Low Hazard 15 ftFrequently Asked Questions
What is the hazard classification of Castle Rock Reservoir Dam?
Castle Rock Reservoir 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 Reservoir Dam?
Castle Rock Reservoir 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 Reservoir Dam built?
Castle Rock Reservoir 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 Reservoir Dam?
Castle Rock Reservoir 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 Reservoir Dam?
Castle Rock Reservoir Dam has a dam height of 67 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 Reservoir Dam last inspected?
Castle Rock Reservoir Dam was last inspected on July 15, 2015. Inspection dates indicate when a formal review occurred, not the results of that inspection.