Mill Creek Storage Dam
Key Takeaway
Mill Creek Storage Dam is classified as high hazard in Washington. It was completed in 1942 and is 84 years old. Its primary use is flood risk reduction. 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 | 3,200 ft |
| Dam Type | Earth |
| Max Storage | 8.3K acre-ft |
| Normal Storage | 3.3K acre-ft |
| Surface Area | 25 acres |
| Drainage Area | 80 sq mi |
| Max Discharge | 17,000 cfs |
| Year Completed | 1942 (84 years old) |
| NID ID | WA00348 |
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
USACE - Walla Walla District
Federal Government
Nearby Dams
Frequently Asked Questions
What is the hazard classification of Mill Creek Storage Dam?
Mill Creek Storage 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 Mill Creek Storage Dam?
Mill Creek Storage Dam is owned by USACE - Walla Walla District (Federal Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Mill Creek Storage Dam built?
Mill Creek Storage Dam was completed in 1942, making it 84 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 Mill Creek Storage Dam?
Mill Creek Storage Dam serves the following purposes: Flood Risk Reduction, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
When was Mill Creek Storage Dam last inspected?
Mill Creek Storage Dam was last inspected on October 20, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.