Big Mac #1
Key Takeaway
Big Mac #1 is classified as low hazard in Montana. It was completed in 1947 and is 79 years old. Its primary use is fire protection.
Physical Details
| Dam Height | 35 ft (taller than 92.6% in MT) |
| Dam Length | 500 ft |
| Dam Type | Earth |
| Max Storage | 157 acre-ft |
| Normal Storage | 99 acre-ft |
| Drainage Area | 3 sq mi |
| Year Completed | 1947 (79 years old) |
| NID ID | MT02664 |
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
MACDONALD, JOHN J & SONS
Private
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Low Hazard 18 ftFrequently Asked Questions
What is the hazard classification of Big Mac #1?
Big Mac #1 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 Big Mac #1?
Big Mac #1 is owned by MACDONALD, JOHN J & SONS (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Big Mac #1 built?
Big Mac #1 was completed in 1947, making it 79 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 Big Mac #1?
Big Mac #1 serves the following purposes: Fire Protection, Stock, Or Small Fish Pond. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Big Mac #1?
Big Mac #1 has a dam height of 35 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.