Mill Creek
Key Takeaway
Mill Creek is classified as high hazard in California. It was completed in 1889 and is 137 years old. Its primary use is water supply. 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 | 76 ft (taller than 75% in CA) |
| Dam Length | 250 ft |
| Dam Type | Earth |
| Max Storage | 223 acre-ft |
| Surface Area | 12 acres |
| Drainage Area | 1 sq mi |
| Year Completed | 1889 (137 years old) |
| NID ID | CA00688 |
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
Lockheed Martin Space Systems Company
Private
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What is the hazard classification of Mill Creek?
Mill Creek 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?
Mill Creek is owned by Lockheed Martin Space Systems Company (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Mill Creek built?
Mill Creek was completed in 1889, making it 137 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?
Mill Creek serves the following purposes: Water Supply, Tailings. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Mill Creek?
Mill Creek has a dam height of 76 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 Mill Creek last inspected?
Mill Creek was last inspected on April 25, 2023. Inspection dates indicate when a formal review occurred, not the results of that inspection.