Grinding Rock
Key Takeaway
Grinding Rock is classified as low hazard in California. It was completed in 1979 and is 47 years old. Its primary use is water supply.
Physical Details
| Dam Height | 55 ft (taller than 63.8% in CA) |
| Dam Length | 525 ft |
| Dam Type | Earth |
| Max Storage | 330 acre-ft |
| Surface Area | 14 acres |
| Drainage Area | 0 sq mi |
| Year Completed | 1979 (47 years old) |
| NID ID | CA01184 |
Safety Information
No probable loss of human life and low economic/environmental losses expected.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
Tuolumne City Sanitary District
Public Utility
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High Hazard 168 ftFrequently Asked Questions
What is the hazard classification of Grinding Rock?
Grinding Rock is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates Grinding Rock?
Grinding Rock is owned by Tuolumne City Sanitary District (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Grinding Rock built?
Grinding Rock was completed in 1979, making it 47 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 Grinding Rock?
Grinding Rock serves the following purposes: Water Supply, Other, Irrigation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Grinding Rock?
Grinding Rock has a dam height of 55 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 Grinding Rock last inspected?
Grinding Rock was last inspected on May 24, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.