Modesto Reservoir
Key Takeaway
Modesto Reservoir is classified as high hazard in California. It was completed in 1911 and is 115 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 | 36 ft (taller than 40.1% in CA) |
| Dam Length | 1,235 ft |
| Dam Type | Earth |
| Max Storage | 40.0K acre-ft |
| Surface Area | 3,800 acres |
| Drainage Area | 10 sq mi |
| Year Completed | 1911 (115 years old) |
| NID ID | CA00243 |
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
Modesto Irrigation District
Public Utility
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Low Hazard 31 ftFrequently Asked Questions
What is the hazard classification of Modesto Reservoir?
Modesto Reservoir 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 Modesto Reservoir?
Modesto Reservoir is owned by Modesto Irrigation District (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Modesto Reservoir built?
Modesto Reservoir was completed in 1911, making it 115 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 Modesto Reservoir?
Modesto Reservoir serves the following purposes: Water Supply, Irrigation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Modesto Reservoir?
Modesto Reservoir has a dam height of 36 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 Modesto Reservoir last inspected?
Modesto Reservoir was last inspected on April 13, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.