Lower Bear is a rockfill dam located in Amador County, California, built in 1952. It carries a High hazard potential classification and has a satisfactory condition assessment.
Dam profile
NID height · 245 ft245 ft tall and 1,844 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 rockfill embankment section and the water level is illustrative.
About Lower Bear
The primary purpose of Lower Bear is hydroelectric. The dam generates hydroelectric power by channeling water through turbines, converting the energy of flowing water into electricity. The dam is owned by Pacific Gas and Electric Company (private). It impounds the Bear River near Pioneer.
The dam stands 245 feet tall and stretches 1,844 feet across, creates a reservoir covering 746 acres, has a maximum storage capacity of 52,025 acre-feet, and collects water from a drainage area of 37 square miles. Completed in 1952, the structure is well into its service life at over 50 years 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 08/20/2025.
At 245 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 | Amador |
| Nearest City | Pioneer |
| River/Stream | Bear River |
| Coordinates | 38.53781, -120.25538 |
Physical Characteristics
| Dam Type | Rockfill |
| NID Height | 245 ft |
| Dam Height | 245 ft |
| Dam Length | 1,844 ft |
| Year Completed | 1952 (74 years old) |
Storage & Hydraulics
| NID Storage | 52,025 acre-ft |
| Max Storage | 52,025 acre-ft |
| Normal Storage | 49,100 acre-ft |
| Surface Area | 746 acres |
| Drainage Area | 37 sq mi |
| Max Discharge | 22,210 cfs |
| Spillway Type | Controlled |
Ownership & Safety
| Purpose | Hydroelectric |
| Owner | Pacific Gas and Electric Company |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 08/20/2025 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | CA00409 |
| Federal ID | CA00409 |
| More Info | State Dam Safety Program |