Twin (Turtle) Lake
Key Takeaway
Twin (Turtle) Lake is classified as high hazard in Montana. It was completed in 1932 and is 94 years old. 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 Length | 1,200 ft |
| Dam Type | Earth |
| Normal Storage | 1.2K acre-ft |
| Year Completed | 1932 (94 years old) |
| NID ID | MT00597 |
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
BIA
Federal Government
Nearby Dams
Frequently Asked Questions
What is the hazard classification of Twin (Turtle) Lake?
Twin (Turtle) Lake 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 Twin (Turtle) Lake?
Twin (Turtle) Lake is owned by BIA (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Twin (Turtle) Lake built?
Twin (Turtle) Lake was completed in 1932, making it 94 years old. Many U.S. dams were built between the 1930s and 1970s during a period of major infrastructure investment.
When was Twin (Turtle) Lake last inspected?
Twin (Turtle) Lake was last inspected on April 20, 2011. Inspection dates indicate when a formal review occurred, not the results of that inspection.