Mary Street
Key Takeaway
Mary Street is classified as high hazard in California. It was completed in 1981 and is 45 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 Height | 40 ft (taller than 46.3% in CA) |
| Dam Length | 1,035 ft |
| Dam Type | Earth |
| Max Storage | 320 acre-ft |
| Surface Area | 19 acres |
| Drainage Area | 7 sq mi |
| Year Completed | 1981 (45 years old) |
| NID ID | CA01211 |
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
Riverside County Flood Control and Water Conservation District
Local Government
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What is the hazard classification of Mary Street?
Mary Street 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 Mary Street?
Mary Street is owned by Riverside County Flood Control and Water Conservation District (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Mary Street built?
Mary Street was completed in 1981, making it 45 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 Mary Street?
Mary Street serves the following purposes: Flood Risk Reduction. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Mary Street?
Mary Street has a dam height of 40 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 Mary Street last inspected?
Mary Street was last inspected on March 9, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.