Tomah Lake dam
Tomah Lake
Tomah Lake, located in Monroe County, Wisconsin, is a man-made reservoir on the Lemonweir River with a high hazard potential due to its 16-foot earth dam. The dam, completed in 1936, has a storage capacity of 2,250 acre-feet and serves multiple purposes, including flood control and water supply. The lake covers an area of 225 acres and has a normal storage capacity of 980 acre-feet, making it an important resource for the local community.
Despite its age, Tomah Lake is well-maintained and regularly inspected by the Wisconsin Department of Natural Resources to ensure its structural integrity and safety. The dam has been modified in 1937 and 1991 for improvements, and it features a controlled spillway with a width of 42 feet. The risk assessment for the dam is classified as very high, highlighting the importance of ongoing risk management measures to mitigate potential hazards and protect the surrounding area from flooding. With its picturesque location and vital role in water resource management, Tomah Lake is a significant asset for both the environment and the community.
Dam data reference
Condition Assessment
- Satisfactory
- No existing or potential dam safety deficiencies are recognized. Acceptable performance is expected under all loading conditions (static, hydrologic, seismic) in accordance with the minimum applicable state or federal regulatory criteria or tolerable risk guidelines.
- Fair
- No existing dam safety deficiencies are recognized for normal operating conditions. Rare or extreme hydrologic and/or seismic events may result in a dam safety deficiency. Risk may be in the range to take further action.
- Poor
- A dam safety deficiency is recognized for normal operating conditions which may realistically occur. Remedial action is necessary. POOR may also be used when uncertainties exist as to critical analysis parameters which identify a potential dam safety deficiency.
- Unsatisfactory
- A dam safety deficiency is recognized that requires immediate or emergency remedial action for problem resolution.
- Not Rated
- The dam has not been inspected, is not under state or federal jurisdiction, or has been inspected but, for whatever reason, has not been rated.
Hazard Potential Classification
- High
- Dams assigned the high hazard potential classification are those where failure or mis-operation will probably cause loss of human life.
- Significant
- Dams assigned the significant hazard potential classification are those dams where failure or mis-operation results in no probable loss of human life but can cause economic loss, environmental damage, disruption of lifeline facilities, or impact other concerns. Significant hazard potential classification dams are often located in predominantly rural or agricultural areas but could be in areas with population and significant infrastructure.
- Low
- Dams assigned the low hazard potential classification are those where failure or mis-operation results in no probable loss of human life and low economic and/or environmental losses. Losses are principally limited to the owner's property.
- Undetermined
- Dams for which a downstream hazard potential has not been designated or is not provided.
Plan around the weather
Same NOAA / yr.no feed Snoflo's iOS app uses. Watch the precipitation column on the meteogram -- rain on the basin upstream typically lifts inflow 24-72 hours later.
Next 5 days, hour by hour
Temperature line with weather symbols on top, snow + rain accumulation as columns, humidity as a dotted line.
5-day forecast table
Every 3 hours, broken out across temperature, snow, rain, humidity, and wind. Each cell is colour-coded relative to the column min/max.
| Time | Condition | Temp (°F) | Snow (in) | Rain (in) | Humidity (%) | Wind (mps) | Wind dir |
|---|---|---|---|---|---|---|---|
| Loading detailed forecast… | |||||||
15-day temperature & precipitation
Daily temperatures, snow, and rain projected over the next two weeks.
Nearby streamflow gauges
USGS streamgauges around Tomah Lake -- inflows here typically show up in storage 24-72 hours later.
| Streamgauge | Discharge | View |
|---|---|---|
| La Crosse River At Sparta | 209 cfs | → |
| Kickapoo River At State Highway 33 At Ontario | 149 cfs | → |
| Lemonweir River At New Lisbon | 326 cfs | → |
| Yellow River At Necedah | 253 cfs | → |
| Black River Ds St Hwy 54 @ Black River Falls | 1,070 cfs | → |
| Kickapoo River At La Farge | 250 cfs | → |
Make a day of it
Boat launches, lakeside camping, fishing access, and other reservoirs near Tomah Lake.
Boat launches
- Winnebago Park
- Town Of Angelo
- Potter Flowage -- Access
- State Highway 131 La Farge
- Little Yellow River/Wisconsin River -- Access
- Castle Rock Lake -- Buckhorn Wildlife Area- Nr 32nd And 16th
Campgrounds
- Pine View Military - Fort Mccoy
- Mill Bluff Campground
- Mill Bluff State Park
- Mcmullen Park Campground
- Mcmullen County Park
- Village Of Wilton Campground
More reservoirs
Track Tomah Lake in the Snoflo app
Save this dam as a favorite and get the local NOAA / yr.no forecast plus regional flow context wherever you are.
About Tomah Lake
Where does the data for Tomah Lake come from?
Structural and regulatory data come from the U.S. Army Corps of Engineers' National Inventory of Dams (NID). Weather forecast comes from NOAA / yr.no -- the same feed Snoflo's iOS app uses.
How often is the report updated?
NID structural data refreshes annually as the Corps publishes updated assessments. The weather forecast refreshes throughout the day.
What does the High hazard rating mean?
The Corps of Engineers' hazard potential classification grades probable consequences if the dam fails: High = probable loss of human life; Significant = no probable loss of human life but possible economic loss / environmental damage; Low = no probable loss of human life, only minor economic / environmental losses. See the Dam Data Reference card above for the full definitions.
What's "% of normal"?
The current storage value compared to the historical average storage on this calendar day. 100% = right on average; values above 100% mean above-normal storage (wet year); values below mean below-normal (dry year or drought).
Can I get alerts when storage crosses a threshold?
Yes -- alerts are managed in the Snoflo iOS app. Favorite this dam, set a threshold, and you'll get a push the moment conditions cross.
Other water bodies near here
Snoflo-tracked reservoirs and dams within driving distance of Tomah Lake.