Flat Lake
Douglas County, Wisconsin65 acresView mapDirections
No nutrient or algae sampling on record from Wisconsin DNR for this lake.
- 3 ft max depth
Flat Lake in Douglas County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Maximum depth: 3.3 ft. Surface area: 65 acres.
Flat Lake is a 65-acre lake in Douglas County, Wisconsin with a maximum depth of 3 feet.
Source: EPA Water Quality Portal sampling records, Wisconsin DNR Surface Water. Methodology: how these readings are compared.
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Flat Lake is safe to swim in today is a call for the Wisconsin Department of Natural Resources and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Flat Lake
These are the measurements Wisconsin DNR publishes for Flat Lake, shown as reported. The condition class beside each reading is the EPA National Lakes Assessment class for this lake’s ecoregion.
No clarity data. TSI undefined.
Ask about Flat Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
3.3 ft
Surface area
65 acres
Shoreline
2 mi
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Fishing Flat Lake
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Frequently asked questions about Flat Lake
Where is Flat Lake?
- Flat Lake is a lake in Douglas County, Wisconsin. Its water-quality measurements are published by Wisconsin DNR and shown on this page as reported.
What is the water quality of Flat Lake?
- Flat Lake in Douglas County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Maximum depth: 3.3 ft. Surface area: 65 acres.
Is Flat Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Flat Lake?
- Flat Lake has a maximum depth of 3.3 feet. The lake covers 65 acres.
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Where this data comes from
Measurements for Flat Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.