Mahan and Hoyt Reservoir
Key Takeaway
Mahan and Hoyt Reservoir is classified as low hazard in Montana. It was completed in 1915 and is 111 years old. Its primary use is irrigation.
Physical Details
| Dam Height | 8 ft (taller than 0.5% in MT) |
| Dam Length | 3,195 ft |
| Dam Type | Earth |
| Max Storage | 864 acre-ft |
| Normal Storage | 364 acre-ft |
| Drainage Area | 3 sq mi |
| Year Completed | 1915 (111 years old) |
| NID ID | MT03024 |
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
WESEN FAMILY
Private
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Low Hazard 9 ftFrequently Asked Questions
What is the hazard classification of Mahan and Hoyt Reservoir?
Mahan and Hoyt Reservoir 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 Mahan and Hoyt Reservoir?
Mahan and Hoyt Reservoir is owned by WESEN FAMILY (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Mahan and Hoyt Reservoir built?
Mahan and Hoyt Reservoir was completed in 1915, making it 111 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 Mahan and Hoyt Reservoir?
Mahan and Hoyt Reservoir 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 Mahan and Hoyt Reservoir?
Mahan and Hoyt Reservoir has a dam height of 8 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 Mahan and Hoyt Reservoir last inspected?
Mahan and Hoyt Reservoir was last inspected on July 1, 2003. Inspection dates indicate when a formal review occurred, not the results of that inspection.