Tomah Lake

Tomah Lake is an earth dam located in Monroe County, Wisconsin, built in 1936. It carries a High hazard potential classification and has a satisfactory condition assessment.

About Tomah Lake

Tomah Lake is a dam in Monroe, Wisconsin. The dam is owned by City Of Tomah (local government). It impounds the Lemonweir near Tomah.

The dam stands 16 feet tall and stretches 1,657 feet across, creates a reservoir covering 225 acres, has a maximum storage capacity of 2,250 acre-feet, and collects water from a drainage area of 30 square miles. Completed in 1936, the structure is well-established, with more than 75 years of service.

This dam carries a high hazard potential classification, which means that a failure or uncontrolled release of water would likely cause loss of human life. This classification reflects the consequences of failure, not the likelihood — it indicates that people live or work in the area downstream. Its condition is rated satisfactory, indicating no existing or potential dam safety deficiencies are recognized. An emergency action plan is in place for this dam. The most recent inspection on record was 07/30/2021.

Living Downstream

If you live or work downstream of this dam, consider taking these steps: learn your local evacuation routes, check whether your county emergency management office has a dam failure inundation map, and sign up for local emergency alerts. The Wisconsin dam safety program can provide more specific information about emergency planning for this structure.

Search for dams near your address to see all dams in your area with hazard classifications and safety data.

High HazardSatisfactory ConditionEmergency Action Plan: Yes

Location

StateWisconsin
CountyMonroe
Nearest CityTomah
River/StreamLemonweir
Coordinates43.98702, -90.51581

Physical Characteristics

Dam TypeEarth
NID Height16 ft
Dam Height16 ft
Dam Length1,657 ft
Year Completed1936 (90 years old)

Storage & Hydraulics

NID Storage2,250 acre-ft
Max Storage2,250 acre-ft
Normal Storage980 acre-ft
Surface Area225 acres
Drainage Area30 sq mi
Max Discharge3,500 cfs
Spillway TypeControlled

Ownership & Safety

OwnerCity Of Tomah
Owner TypeLocal Government
Hazard ClassificationHigh
Condition AssessmentSatisfactory
Last Inspection07/30/2021
Emergency Action PlanYes

Identifiers

NID IDWI00161
Federal IDWI00161
More InfoState Dam Safety Program

Nearby Dams