Fourth Lake
Oneida County, Wisconsin253 acresView mapDirections
No nutrient or algae sampling on record from Wisconsin DNR for this lake.
- Impaired · Mercury
- 14 ft max depth
Fourth Lake in Oneida County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Maximum depth: 14 ft. Surface area: 253 acres.
Fourth Lake is a 253-acre lake in Oneida County, Wisconsin with a maximum depth of 14 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. Fourth Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
Whether Fourth 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 Fourth Lake
These are the measurements Wisconsin DNR publishes for Fourth 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 Fourth Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
14 ft
Surface area
253 acres
Shoreline
2.7 mi
Stays via Stay22
Stays near Fourth Lake
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Fishing Fourth Lake
EPA Impairment Status
Fourth Lake is officially listed as impaired under Clean Water Act §303(d) in the 2024 EPA reporting cycle (IR category 5).
Causes of impairment
Designated uses not supporting: Fish consumption.
Source: EPA ATTAINS assessment unit WI10007284 · Official waterbody report
Nearby Lakes in Oneida County
Frequently asked questions about Fourth Lake
Where is Fourth Lake?
- Fourth Lake is a lake in Oneida County, Wisconsin. Its water-quality measurements are published by Wisconsin DNR and shown on this page as reported.
What is the water quality of Fourth Lake?
- Fourth Lake in Oneida County, Wisconsin has water-quality measurements published by Wisconsin DNR, shown here as reported. Maximum depth: 14 ft. Surface area: 253 acres.
Is Fourth Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Fourth Lake is listed impaired under Clean Water Act §303(d) (IR 5) for mercury. Check local advisories before you swim.
How deep is Fourth Lake?
- Fourth Lake has a maximum depth of 14 feet. The lake covers 253 acres.
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Where this data comes from
Measurements for Fourth Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Impairment status from EPA ATTAINS 303(d) database