Lake Jefferson

BIG CANNON RIVER - TR· Le Sueur, Minnesota· Built 1938· Gravity· 7 ft tall
Low Hazard Recreation State Government

Key Takeaway

Lake Jefferson is classified as low hazard in Minnesota. It was completed in 1938 and is 88 years old. Its primary use is recreation.

Physical Details

Dam Height 7 ft (taller than 8.5% in MN)
Dam Length15 ft
Dam TypeGravity
Max Storage25.5K acre-ft
Normal Storage18.5K acre-ft
Surface Area700 acres
Drainage Area16 sq mi
Max Discharge265 cfs
Year Completed1938 (88 years old)
NID IDMN00155

Safety Information

Low Hazard

No probable loss of human life and low economic/environmental losses expected.

Hazard potential describes downstream consequences of failure, not the dam's current condition. What does this mean?

Emergency Action Plan: No
Last Inspection: May 27, 2008
State Regulated: No

Ownership

MNDNR-Trails

State Government

Nearby Dams

Frequently Asked Questions

What is the hazard classification of Lake Jefferson?

Lake Jefferson is classified as Low Hazard. No probable loss of human life and low economic/environmental losses expected. This classification refers to the potential downstream consequences of a failure, not the dam's current structural condition.

Who owns and operates Lake Jefferson?

Lake Jefferson is owned by MNDNR-Trails (State Government). The owner is responsible for maintenance, inspections, and compliance with dam safety regulations.

When was Lake Jefferson built?

Lake Jefferson was completed in 1938, making it 88 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 Lake Jefferson?

Lake Jefferson 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 Lake Jefferson?

Lake Jefferson has a dam height of 7 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 Lake Jefferson last inspected?

Lake Jefferson was last inspected on May 27, 2008. 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.