Johnson Falls
Key Takeaway
Johnson Falls is classified as high hazard in Wisconsin. It was completed in 1923 and is 103 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 | 43 ft (taller than 94.9% in WI) |
| Dam Length | 511 ft |
| Dam Type | Gravity |
| Max Storage | 2.5K acre-ft |
| Normal Storage | 2.5K acre-ft |
| Surface Area | 130 acres |
| Drainage Area | 647 sq mi |
| Max Discharge | 21,000 cfs |
| Year Completed | 1923 (103 years old) |
| NID ID | WI00758 |
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
Wisconsin Public Service Corporation
Public Utility
Nearby Dams
Frequently Asked Questions
What is the hazard classification of Johnson Falls?
Johnson Falls 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 Johnson Falls?
Johnson Falls is owned by Wisconsin Public Service Corporation (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Johnson Falls built?
Johnson Falls was completed in 1923, making it 103 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 Johnson Falls?
Johnson Falls 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 Johnson Falls?
Johnson Falls has a dam height of 43 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 Johnson Falls last inspected?
Johnson Falls was last inspected on September 7, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.