Lois Lake
Key Takeaway
Lois Lake is classified as low hazard in Montana. It was completed in 1966 and is 60 years old. Its primary use is irrigation.
Physical Details
| Dam Height | 23 ft (taller than 66.4% in MT) |
| Dam Length | 400 ft |
| Dam Type | Earth |
| Max Storage | 288 acre-ft |
| Normal Storage | 221 acre-ft |
| Surface Area | 26 acres |
| Drainage Area | 7 sq mi |
| Max Discharge | 230 cfs |
| Year Completed | 1966 (60 years old) |
| NID ID | MT01226 |
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
GARY HARRISON
Private
Nearby Dams
Frequently Asked Questions
What is the hazard classification of Lois Lake?
Lois Lake 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 Lois Lake?
Lois Lake is owned by GARY HARRISON (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Lois Lake built?
Lois Lake was completed in 1966, making it 60 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 Lois Lake?
Lois Lake 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 Lois Lake?
Lois Lake has a dam height of 23 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.