Big Twin Lake
Mason County, Washington81 acresView mapDirections
No nutrient or algae sampling on record from Washington Ecology for this lake.
Big Twin Lake in Mason County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Surface area: 81 acres.
Big Twin Lake is a 81-acre lake in Mason County, Washington.
Source: EPA Water Quality Portal sampling records, WA Ecology. 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 Big Twin Lake is safe to swim in today is a call for the Washington State Department of Ecology and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Big Twin Lake
These are the measurements Washington Ecology publishes for Big Twin 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 Big Twin Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
81 acres
Shoreline
2.4 mi
No bathymetric survey has been published for Big Twin Lake, so its depth is not documented here.
Stays via Stay22
Stays near Big Twin Lake
Compare lakeside cabins, hotels, and vacation rentals near Big Twin Lake in Mason County, Washington — 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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Fishing Big Twin Lake
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Frequently asked questions about Big Twin Lake
Where is Big Twin Lake?
- Big Twin Lake is a lake in Mason County, Washington. Its water-quality measurements are published by Washington Ecology and shown on this page as reported.
What is the water quality of Big Twin Lake?
- Big Twin Lake in Mason County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Surface area: 81 acres.
Is Big Twin 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 Big Twin Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.