Long Lake

BRILL· Washburn, Wisconsin· Built 1913· Gravity· 15 ft tall
High Hazard Recreation Local Government

Key Takeaway

Long Lake is classified as high hazard in Wisconsin. It was completed in 1913 and is 113 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 15 ft (taller than 45% in WI)
Dam Length575 ft
Dam TypeGravity
Max Storage35.0K acre-ft
Normal Storage15.0K acre-ft
Surface Area3,290 acres
Drainage Area82 sq mi
Max Discharge2,660 cfs
Year Completed1913 (113 years old)
NID IDWI00325

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: May 7, 2020
State Regulated: Yes
Regulatory Agency: WIDNR

Ownership

Washburn County

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Long Lake?

Long 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 Long Lake?

Long Lake is owned by Washburn County (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Long Lake built?

Long Lake was completed in 1913, making it 113 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 Long Lake?

Long 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 Long Lake?

Long Lake has a dam height of 15 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 Long Lake last inspected?

Long Lake was last inspected on May 7, 2020. 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.