Jack Lake
Mason County, Illinois1,501 acresView mapDirections
No nutrient or algae sampling on record from Illinois EPA for this lake.
Jack Lake in Mason County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Surface area: 1501 acres.
Jack Lake is a 1,501-acre lake in Mason County, Illinois.
Source: EPA Water Quality Portal sampling records, Illinois EPA. Methodology: how these readings are compared.
What Jack Lake is good for
From access and monitoring records, not editorial picks.
- Big water1,501 acres
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Jack 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 Jack Lake
These are the measurements Illinois EPA publishes for Jack 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 Jack Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
1,501 acres
Shoreline
12.5 mi
No bathymetric survey has been published for Jack Lake, so its depth is not documented here.
Stays via Stay22
Stays near Jack Lake
Compare lakeside cabins, hotels, and vacation rentals near Jack Lake in Mason County, Illinois — live availability and prices for your trip. Switch the map to Satellite to see the lake and how close each stay is to the water.
Top-rated places to stay near Jack Lake
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Fishing Jack Lake
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Frequently asked questions about Jack Lake
Where is Jack Lake?
- Jack Lake is a lake in Mason County, Illinois. Its water-quality measurements are published by Illinois EPA and shown on this page as reported.
What is the water quality of Jack Lake?
- Jack Lake in Mason County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Surface area: 1501 acres.
Is Jack Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
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Where this data comes from
Measurements for Jack Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.