Hanson CO #11
Key Takeaway
Hanson CO #11 is classified as low hazard in Montana. It was completed in 1962 and is 64 years old. Its primary use is irrigation.
Physical Details
| Dam Height | 15 ft (taller than 18.8% in MT) |
| Dam Length | 275 ft |
| Dam Type | Earth |
| Max Storage | 135 acre-ft |
| Normal Storage | 61 acre-ft |
| Drainage Area | 1 sq mi |
| Max Discharge | 800 cfs |
| Year Completed | 1962 (64 years old) |
| NID ID | MT01936 |
Safety Information
No probable loss of human life and low economic/environmental losses expected.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
HANSON SHEEP CO
Private
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Low Hazard 20 ftFrequently Asked Questions
What is the hazard classification of Hanson CO #11?
Hanson CO #11 is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Hanson CO #11?
Hanson CO #11 is owned by HANSON SHEEP CO (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Hanson CO #11 built?
Hanson CO #11 was completed in 1962, making it 64 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 Hanson CO #11?
Hanson CO #11 serves the following purposes: Irrigation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Hanson CO #11?
Hanson CO #11 has a dam height of 15 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.