Upper Green Lake
Key Takeaway
Upper Green Lake is classified as high hazard in Wisconsin. It was completed in 1869 and is 157 years old. Its primary use is recreation. 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 | 8 ft (taller than 5.5% in WI) |
| Dam Length | 200 ft |
| Dam Type | Gravity |
| Max Storage | 40.0K acre-ft |
| Normal Storage | 30.0K acre-ft |
| Surface Area | 7,346 acres |
| Drainage Area | 115 sq mi |
| Max Discharge | 414 cfs |
| Year Completed | 1869 (157 years old) |
| NID ID | WI00633 |
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
City Of Green Lake
Local Government
Nearby Dams
Frequently Asked Questions
What is the hazard classification of Upper Green Lake?
Upper Green Lake 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 Upper Green Lake?
Upper Green Lake is owned by City Of Green Lake (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.
When was Upper Green Lake built?
Upper Green Lake was completed in 1869, making it 157 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 Upper Green Lake?
Upper Green Lake serves the following purposes: Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.
How tall is Upper Green Lake?
Upper Green Lake has a dam height of 8 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 Upper Green Lake last inspected?
Upper Green Lake was last inspected on October 5, 2021. Inspection dates indicate when a formal review occurred, not the results of that inspection.