Otter Lake
Mason County, Illinois301 acresView mapDirections
No nutrient or algae sampling on record from Illinois EPA for this lake.
Otter Lake in Mason County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Surface area: 301 acres.
Otter Lake is a 301-acre lake in Mason County, Illinois.
Source: EPA Water Quality Portal sampling records, Illinois EPA. 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 Otter 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 Otter Lake
These are the measurements Illinois EPA publishes for Otter 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 Otter Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
301 acres
Shoreline
4.3 mi
No bathymetric survey has been published for Otter Lake, so its depth is not documented here.
Stays via Stay22
Stays near Otter Lake
Compare lakeside cabins, hotels, and vacation rentals near Otter 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.
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Frequently asked questions about Otter Lake
Where is Otter Lake?
- Otter 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 Otter Lake?
- Otter Lake in Mason County, Illinois has water-quality measurements published by Illinois EPA, shown here as reported. Surface area: 301 acres.
Is Otter 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 Otter Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.