Green Lake is a lake in King County, Washington. Its water-quality measurements are published by Washington Ecology and shown on this page as reported.

Green Lake

King County, Washington250 acresView map Directions

No nutrient or algae sampling on record from Washington Ecology for this lake.

Area

250 acres

Surface area

Shoreline

2.9 mi

Measured length

Impaired · Dioxins

See the measurements Directions Where to stay

Green Lake in King County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Surface area: 250 acres.

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Green Lake is a 250-acre lake in King County, Washington.

Source: EPA Water Quality Portal sampling records, WA Ecology. Methodology: how these readings are compared.

Swimming conditions

No reading

Not rated

Nutrient and algae readings are not a swimming clearance. Green Lake is listed impaired under Clean Water Act §303(d) (IR 5) for dioxins, mercury, nuisance exotic species, pesticides, pCBs. Check local advisories before you swim.

Whether Green 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.

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Water quality measurements for Green Lake

These are the measurements Washington Ecology publishes for Green 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 Green Lake

Answers come straight from the public measurements and survey records on this page.

Lake Details

Surface area

250 acres

Shoreline

2.9 mi

No bathymetric survey has been published for Green Lake, so its depth is not documented here.

Stays via Stay22

Stays near Green Lake

Compare lakeside cabins, hotels, and vacation rentals near Green Lake in King 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.

Top-rated places to stay near Green Lake

Prices for Oct 16–18, 4 adults. Change dates on the map below.

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Fishing Green Lake

→ Green Lake fishing regulations (limits, seasons, special rules)

EPA Impairment Status

Green Lake is officially listed as impaired under Clean Water Act §303(d) in the 2018 EPA reporting cycle (IR category 5).

Causes of impairment

DioxinsMercuryNuisance exotic speciesPesticidesPCBs

Designated uses not supporting: Drinking water, Aquatic life, Fish consumption.

Source: EPA ATTAINS assessment unit WA17110012000401_001_001 · Official waterbody report

Nearby Lakes in King County

Lake Union2.6 miView →Lake Washington Ship Canal2.4 miView →Lake Washington5 miView →Burien Lake—View →Phantom Lake11.6 miView →Angle Lake20 ft clear—View →

Frequently asked questions about Green Lake

Where is Green Lake?: Green Lake is a lake in King County, Washington. Its water-quality measurements are published by Washington Ecology and shown on this page as reported.
What is the water quality of Green Lake?: Green Lake in King County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Surface area: 250 acres.
Is Green Lake safe to swim in?: Nutrient and algae readings are not a swimming clearance. Green Lake is listed impaired under Clean Water Act §303(d) (IR 5) for dioxins, mercury, nuisance exotic species, pesticides, pCBs. Check local advisories before you swim.