River Mill
River Mill is a buttress dam located in Clackamas County, Oregon, built in 1911. It carries a High hazard potential classification and has a satisfactory condition assessment.
About River Mill
The primary purpose of River Mill 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 Portland General Electric Company (private). It impounds the Clackamas River near Carver, Or.
The dam stands 85 feet tall and stretches 936 feet across, creates a reservoir covering 150 acres, has a storage capacity of 2,300 acre-feet, and collects water from a drainage area of 671 square miles. Completed in 1911, 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 09/20/2022.
At 85 feet, this dam is taller than 97% 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 Oregon 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 | Oregon |
| County | Clackamas |
| Nearest City | Carver, Or |
| River/Stream | Clackamas River |
| Coordinates | 45.29920, -122.35060 |
Physical Characteristics
| Dam Type | Buttress |
| NID Height | 85 ft |
| Dam Height | 85 ft |
| Dam Length | 936 ft |
| Year Completed | 1911 (115 years old) |
Storage & Hydraulics
| NID Storage | 2,300 acre-ft |
| Normal Storage | 2,300 acre-ft |
| Surface Area | 150 acres |
| Drainage Area | 671 sq mi |
| Max Discharge | 150,000 cfs |
| Spillway Type | Uncontrolled |
Ownership & Safety
| Purpose | Hydroelectric |
| Owner | Portland General Electric Company |
| Owner Type | Private |
| Hazard Classification | High |
| Condition Assessment | Satisfactory |
| Last Inspection | 09/20/2022 |
| Emergency Action Plan | Yes |
Identifiers
| NID ID | OR00552 |
| Federal ID | OR00552 |
| More Info | State Dam Safety Program |