Flat Lake
Grant County, Washington74 acresView mapDirections
No nutrient or algae sampling on record from Washington Ecology for this lake.
Flat Lake in Grant County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Surface area: 74 acres.
Flat Lake is a 74-acre lake in Grant 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 Flat 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 Flat Lake
These are the measurements Washington Ecology publishes for Flat 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 Flat Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Surface area
74 acres
No bathymetric survey has been published for Flat Lake, so its depth is not documented here.
Stays via Stay22
Stays near Flat Lake
Compare lakeside cabins, hotels, and vacation rentals near Flat Lake in Grant 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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Frequently asked questions about Flat Lake
Where is Flat Lake?
- Flat Lake is a lake in Grant County, Washington. Its water-quality measurements are published by Washington Ecology and shown on this page as reported.
What is the water quality of Flat Lake?
- Flat Lake in Grant County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Surface area: 74 acres.
Is Flat 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 Flat Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.