Mountain Lake Dam
Key Takeaway
Mountain Lake Dam is classified as high hazard in Washington. It was completed in 1905 and is 121 years old. Its primary use is recreation. 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 Length | 172 ft |
| Dam Type | Rockfill |
| Max Storage | 3.0K acre-ft |
| Normal Storage | 2.9K acre-ft |
| Surface Area | 180 acres |
| Drainage Area | 2 sq mi |
| Max Discharge | 200 cfs |
| Year Completed | 1905 (121 years old) |
| NID ID | WA00279 |
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
WA PARKS
State Government
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Low HazardFrequently Asked Questions
What is the hazard classification of Mountain Lake Dam?
Mountain Lake 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 Mountain Lake Dam?
Mountain Lake Dam is owned by WA PARKS (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Mountain Lake Dam built?
Mountain Lake Dam was completed in 1905, making it 121 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 Mountain Lake Dam?
Mountain Lake Dam serves the following purposes: Recreation, Water Supply. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
When was Mountain Lake Dam last inspected?
Mountain Lake Dam was last inspected on November 17, 2023. Inspection dates indicate when a formal review occurred, not the results of that inspection.