Warnes Slough
Sully County, South Dakota365 acresView mapDirections
No nutrient or algae sampling on record from SD DANR for this lake.
Warnes Slough in Sully County, South Dakota has water-quality measurements published by SD DANR, shown here as reported. Surface area: 365 acres.
Warnes Slough is a 365-acre lake in Sully County, South Dakota.
Source: EPA Water Quality Portal sampling records, SD DANR. 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 Warnes Slough is safe to swim in today is a call for the South Dakota Department of Agriculture and Natural Resources and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Warnes Slough
These are the measurements SD DANR publishes for Warnes Slough, 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 Warnes Slough
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
365 acres
Shoreline
5 mi
No bathymetric survey has been published for Warnes Slough, so its depth is not documented here.
Stays via Stay22
Stays near Warnes Slough
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Fishing Warnes Slough
Nearby Lakes in Sully County
Frequently asked questions about Warnes Slough
Where is Warnes Slough?
- Warnes Slough is a lake in Sully County, South Dakota. Its water-quality measurements are published by SD DANR and shown on this page as reported.
What is the water quality of Warnes Slough?
- Warnes Slough in Sully County, South Dakota has water-quality measurements published by SD DANR, shown here as reported. Surface area: 365 acres.
Is Warnes Slough 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 Warnes Slough come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.