North Fork
Key Takeaway
North Fork is classified as high hazard in Oregon. It was completed in 1958 and is 68 years old. Its primary use is hydroelectric. High hazard means loss of life is likely if the dam fails — it does not indicate the dam's current condition. Learn more.
Physical Details
| Dam Height | 207 ft (taller than 98.3% in OR) |
| Dam Length | 676 ft |
| Dam Type | Arch |
| Normal Storage | 18.6K acre-ft |
| Surface Area | 350 acres |
| Drainage Area | 671 sq mi |
| Max Discharge | 150,000 cfs |
| Year Completed | 1958 (68 years old) |
| NID ID | OR00550 |
Safety Information
Loss of human life is likely if the dam fails.
Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?
Ownership
Portland General Electric Company
Private
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What is the hazard classification of North Fork?
North Fork is classified as High Hazard. Loss of human life is likely if the dam fails. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.
Who owns and operates North Fork?
North Fork is owned by Portland General Electric Company (Private). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was North Fork built?
North Fork was completed in 1958, making it 68 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 North Fork?
North Fork serves the following purposes: Hydroelectric, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is North Fork?
North Fork has a dam height of 207 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 North Fork last inspected?
North Fork was last inspected on September 20, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.