Colstrip Evaporation Pond Dam
Key Takeaway
Colstrip Evaporation Pond 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 | 88 ft (taller than 98.7% in MT) |
| Dam Length | 1,840 ft |
| Dam Type | Earth |
| Max Storage | 3.8K acre-ft |
| Normal Storage | 2.4K acre-ft |
| Surface Area | 35 acres |
| Drainage Area | 1 sq mi |
| Max Discharge | 625 cfs |
| Year Completed | 1976 (50 years old) |
| NID ID | MT03211 |
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
Nearby Dams
Colstrip Diversion Dam
Rosebud, MT
High Hazard 44 ftCastle Rock Reservoir Dam
Rosebud, MT
High Hazard 67 ftCastle Rock Saddle Dam
Rosebud, MT
High Hazard 20 ftLee #9
Rosebud, MT
Low Hazard 20 ftPond No. 10
Rosebud, MT
Low Hazard 31 ftPond No. 11
Rosebud, MT
Low Hazard 22 ftVassaus #11
Rosebud, MT
Low Hazard 20 ftSand #2
Rosebud, MT
Low Hazard 15 ftFrequently Asked Questions
What is the hazard classification of Colstrip Evaporation Pond Dam?
Colstrip Evaporation Pond 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 Colstrip Evaporation Pond Dam?
Colstrip Evaporation Pond Dam is owned by TALEN ENERGY (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Colstrip Evaporation Pond Dam built?
Colstrip Evaporation Pond 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 Colstrip Evaporation Pond Dam?
Colstrip Evaporation Pond 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 Colstrip Evaporation Pond Dam?
Colstrip Evaporation Pond Dam has a dam height of 88 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 Colstrip Evaporation Pond Dam last inspected?
Colstrip Evaporation Pond Dam was last inspected on July 14, 2014. Inspection dates indicate when a formal review occurred, not the results of that inspection.