Twentymile Slough
Lake County, Oregon419 acresView mapDirections
No nutrient or algae sampling on record from Oregon DEQ for this lake.
Twentymile Slough in Lake County, Oregon has water-quality measurements published by Oregon DEQ, shown here as reported. Surface area: 419 acres.
Twentymile Slough is a 419-acre lake in Lake County, Oregon.
Source: EPA Water Quality Portal sampling records, Oregon DEQ. 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 Twentymile Slough is safe to swim in today is a call for the Oregon Department of Environmental Quality and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Twentymile Slough
These are the measurements Oregon DEQ publishes for Twentymile 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 Twentymile Slough
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
419 acres
Shoreline
13.5 mi
No bathymetric survey has been published for Twentymile Slough, so its depth is not documented here.
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Frequently asked questions about Twentymile Slough
Where is Twentymile Slough?
- Twentymile Slough is a lake in Lake County, Oregon. Its water-quality measurements are published by Oregon DEQ and shown on this page as reported.
What is the water quality of Twentymile Slough?
- Twentymile Slough in Lake County, Oregon has water-quality measurements published by Oregon DEQ, shown here as reported. Surface area: 419 acres.
Is Twentymile 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 Twentymile Slough come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.