Roberts
Roberts is an earth dam located in Modoc County, California, built in 1905. It carries a High hazard potential classification and has a satisfactory condition assessment.
About Roberts
Roberts is a dam in Modoc, California. The dam is owned by Big Valley Mutual Water Company (private). It impounds the Tr Pit River near Beiber.
The dam stands 17 feet tall and stretches 700 feet across, creates a reservoir covering 640 acres, has a maximum storage capacity of 5,500 acre-feet, and collects water from a drainage area of 23 square miles. Completed in 1905, 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 06/11/2025.
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 | Modoc |
| Nearest City | Beiber |
| River/Stream | Tr Pit River |
| Coordinates | 41.22940, -121.13730 |
Physical Characteristics
| Dam Type | Earth |
| NID Height | 17 ft |
| Dam Height | 17 ft |
| Dam Length | 700 ft |
| Year Completed | 1905 (121 years old) |
Storage & Hydraulics
| NID Storage | 5,500 acre-ft |
| Max Storage | 5,500 acre-ft |
| Surface Area | 640 acres |
| Drainage Area | 23 sq mi |
Ownership & Safety
| Purpose | Other |
| Owner | Big Valley Mutual Water Company |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 06/11/2025 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CA00485 |
| Federal ID | CA00485 |
| More Info | State Dam Safety Program |