Lake Frances East Dam
Key Takeaway
Lake Frances East Dam is classified as high hazard in Montana. It was completed in 1909 and is 117 years old. Its primary use is irrigation. 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 Height | 59 ft (taller than 97.5% in MT) |
| Dam Length | 800 ft |
| Dam Type | Earth |
| Max Storage | 133.6K acre-ft |
| Normal Storage | 110.5K acre-ft |
| Surface Area | 5,300 acres |
| Drainage Area | 13 sq mi |
| Max Discharge | 636 cfs |
| Year Completed | 1909 (117 years old) |
| NID ID | MT01125 |
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
PONDERA CANAL & RES. CO.
Private
Nearby Dams
Frequently Asked Questions
What is the hazard classification of Lake Frances East Dam?
Lake Frances East Dam 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 Lake Frances East Dam?
Lake Frances East Dam is owned by PONDERA CANAL & RES. CO. (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Lake Frances East Dam built?
Lake Frances East Dam was completed in 1909, making it 117 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 Lake Frances East Dam?
Lake Frances East Dam serves the following purposes: Irrigation, Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Lake Frances East Dam?
Lake Frances East Dam has a dam height of 59 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 Lake Frances East Dam last inspected?
Lake Frances East Dam was last inspected on October 4, 2023. Inspection dates indicate when a formal review occurred, not the results of that inspection.