Third Lake
Lake County, Illinois154 acresView mapDirections
No nutrient or algae sampling on record from Illinois EPA for this lake.
- Impaired · Nutrients (phosphorus, nitrogen)
- 70 ft max depth
Third Lake in Lake County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Maximum depth: 70 ft. Surface area: 154 acres.
Third Lake is a 154-acre lake in Lake County, Illinois with a maximum depth of 70 feet (21-foot average).
Source: EPA Water Quality Portal sampling records, Illinois EPA. Methodology: how these readings are compared.
What Third Lake is good for
From access and monitoring records, not editorial picks.
- Deep water70 ft surveyed max depth
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Third Lake is listed impaired under Clean Water Act §303(d) (IR 5) for nutrients (phosphorus, nitrogen), turbidity. Check local advisories before you swim.
Whether Third Lake is safe to swim in today is a call for the Illinois Environmental Protection Agency and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Third Lake
These are the measurements Illinois EPA publishes for Third 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 Third Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
70 ft
Average depth
20.5 ft
Surface area
154 acres
Shoreline
2 mi
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Stays near Third Lake
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Fishing Third Lake
EPA Impairment Status
Third 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: Other.
Source: EPA ATTAINS assessment unit IL_RGW · Official waterbody report
Nearby Lakes in Lake County
Frequently asked questions about Third Lake
Where is Third Lake?
- Third Lake is a lake in Lake County, Illinois. Its water-quality measurements are published by Illinois EPA and shown on this page as reported.
What is the water quality of Third Lake?
- Third Lake in Lake County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Maximum depth: 70 ft. Surface area: 154 acres.
Is Third Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Third Lake is listed impaired under Clean Water Act §303(d) (IR 5) for nutrients (phosphorus, nitrogen), turbidity. Check local advisories before you swim.
How deep is Third Lake?
- Third Lake has a maximum depth of 70 feet and an average depth of 20.5 feet. The lake covers 154 acres.
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Where this data comes from
Measurements for Third 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