Hat Rapids

Wisconsin River· Oneida, Wisconsin· Built 1923· Gravity· 30 ft tall
High Hazard Hydroelectric Recreation Public Utility

Key Takeaway

Hat Rapids 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 30 ft (taller than 81.6% in WI)
Dam Length1,004 ft
Dam TypeGravity
Max Storage4.8K acre-ft
Normal Storage4.8K acre-ft
Surface Area640 acres
Drainage Area1,143 sq mi
Max Discharge12,900 cfs
Year Completed1923 (103 years old)
NID IDWI00770

Safety Information

High Hazard

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?

Emergency Action Plan: Yes
Last Inspection: August 18, 2022
State Regulated: No

Ownership

Wisconsin Public Service Corporation

Public Utility

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Hat Rapids?

Hat Rapids 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 Hat Rapids?

Hat Rapids is owned by Wisconsin Public Service Corporation (Public Utility). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Hat Rapids built?

Hat Rapids 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 Hat Rapids?

Hat Rapids 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 Hat Rapids?

Hat Rapids has a dam height of 30 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 Hat Rapids last inspected?

Hat Rapids was last inspected on August 18, 2022. Inspection dates indicate when a formal review occurred, not the results of that inspection.

Data from the National Inventory of Dams (NID) maintained by the US Army Corps of Engineers. Dam conditions may have changed since the last update. This site is not affiliated with USACE. Do not use for emergency planning — contact your local dam safety program.