South Fork Tolt Reservoir
King County, Washington1,011 acresView mapDirections
No nutrient or algae sampling on record from Washington Ecology for this lake.
South Fork Tolt Reservoir in King County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Surface area: 1011 acres.
South Fork Tolt Reservoir is a 1,011-acre lake in King County, Washington.
Source: EPA Water Quality Portal sampling records, WA Ecology. Methodology: how these readings are compared.
What South Fork Tolt Reservoir is good for
From access and monitoring records, not editorial picks.
- Big water1,011 acres
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether South Fork Tolt Reservoir 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 South Fork Tolt Reservoir
These are the measurements Washington Ecology publishes for South Fork Tolt Reservoir, 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 South Fork Tolt Reservoir
Answers come straight from the public measurements and survey records on this page.
→ South Fork Tolt Reservoir water level: the live USGS gauge reading
Lake Details
Surface area
1,011 acres
Shoreline
8.7 mi
No bathymetric survey has been published for South Fork Tolt Reservoir, so its depth is not documented here.
Stays via Stay22
Stays near South Fork Tolt Reservoir
Compare lakeside cabins, hotels, and vacation rentals near South Fork Tolt Reservoir 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 South Fork Tolt Reservoir
Prices for Oct 9–11, 4 adults. Change dates on the map below.
Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.
Planning a whole trip? See where to stay at Washington’s top lakes →
Follow South Fork Tolt Reservoir’s readings
Email me when new measurements post for this lake. Updates stay free.
Or email
Fishing South Fork Tolt Reservoir
Nearby Lakes in King County
Frequently asked questions about South Fork Tolt Reservoir
Where is South Fork Tolt Reservoir?
- South Fork Tolt Reservoir 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 South Fork Tolt Reservoir?
- South Fork Tolt Reservoir in King County, Washington has water-quality measurements published by Washington Ecology, shown here as reported. Surface area: 1011 acres.
Is South Fork Tolt Reservoir safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Explore South Fork Tolt Reservoir across LakeQuality
More lakes in Washington
Other Lakes in Washington
Where this data comes from
Measurements for South Fork Tolt Reservoir come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.