Priest is an earth dam located in Tuolumne County, California, built in 1923. It carries a High hazard potential classification and has a satisfactory condition assessment.
Dam profile
NID height · 168 ft168 ft tall and 1,000 ft long, taller than 99% of U.S. dams with a recorded height. Height is drawn to scale against the Statue of Liberty, 305 ft ground to torch; the profile is a generic embankment section and the water level is illustrative.
About Priest
Priest is a dam in Tuolumne, California. The dam is owned by San Francisco Public Utilities Commission (local government). It impounds the Rattlesnake Crk near Moccasin.
The dam stands 168 feet tall and stretches 1,000 feet across, creates a reservoir covering 45 acres, and has a maximum storage capacity of 2,067 acre-feet. Completed in 1923, the structure is over a century old.
This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 02/05/2025.
At 168 feet, this dam is taller than 99% of all dams in the United States.
Living Downstream
If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The California dam safety program can provide more specific information about emergency planning for this structure.
Search for dams near your address to see all dams in your area with hazard classifications and safety data.
Location
| State | California |
| County | Tuolumne |
| Nearest City | Moccasin |
| River/Stream | Rattlesnake Crk |
| Coordinates | 37.80050, -120.26740 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 168 ft |
| Dam Height | 168 ft |
| Dam Length | 1,000 ft |
| Year Completed | 1923 (103 years old) |
Storage & Hydraulics
| NID Storage | 2,067 acre-ft |
| Max Storage | 2,067 acre-ft |
| Surface Area | 45 acres |
Ownership & Safety
| Purpose | Other |
| Owner | San Francisco Public Utilities Commission |
| Owner Type | Local Government |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 02/05/2025 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CA00124 |
| Federal ID | CA00124 |
| More Info | State Dam Safety Program |