Mendota Locks

YAHARA RIVER· Dane, Wisconsin· Built 1849· Other· 16 ft tall
High Hazard Navigation Recreation Local Government

Key Takeaway

Mendota Locks is classified as high hazard in Wisconsin. It was completed in 1849 and is 177 years old. Its primary use is navigation. 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 16 ft (taller than 48.8% in WI)
Dam Length100 ft
Dam TypeOther
Max Storage160.0K acre-ft
Normal Storage132.0K acre-ft
Surface Area9,730 acres
Drainage Area254 sq mi
Max Discharge1,860 cfs
Year Completed1849 (177 years old)
NID IDWI00621

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: June 19, 2020
State Regulated: Yes
Regulatory Agency: WIDNR

Ownership

Dane County

Local Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Mendota Locks?

Mendota Locks 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 Mendota Locks?

Mendota Locks is owned by Dane County (Local Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Mendota Locks built?

Mendota Locks was completed in 1849, making it 177 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 Mendota Locks?

Mendota Locks serves the following purposes: Navigation, Recreation. Many dams in the U.S. are multi-purpose, supporting flood control, water supply, recreation, and other uses.

How tall is Mendota Locks?

Mendota Locks has a dam height of 16 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 Mendota Locks last inspected?

Mendota Locks was last inspected on June 19, 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.