Grass Lake
St. Lawrence County, New York341 acresView mapDirections
No nutrient or algae sampling on record from NY DEC for this lake.
- 51 ft max depth
Grass Lake in St. Lawrence County, New York has water-quality measurements published by NY DEC, shown here as reported. Maximum depth: 50.5 ft. Surface area: 341 acres.
Grass Lake is a 341-acre lake in St. Lawrence County, New York with a maximum depth of 51 feet (24-foot average).
Source: EPA Water Quality Portal sampling records, NYSDEC. Methodology: how these readings are compared.
What Grass Lake is good for
From access and monitoring records, not editorial picks.
- Deep water50.5 ft surveyed max depth
Swimming conditions
No readingNot rated
Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
Whether Grass Lake is safe to swim in today is a call for the New York Department of Environmental Conservation and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Grass Lake
These are the measurements NY DEC publishes for Grass 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 Grass Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
50.5 ft
Average depth
23.6 ft
Surface area
341 acres
Shoreline
7.6 mi
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Fishing Grass Lake
Nearby Lakes in St. Lawrence County
Frequently asked questions about Grass Lake
Where is Grass Lake?
- Grass Lake is a lake in St. Lawrence County, New York. Its water-quality measurements are published by NY DEC and shown on this page as reported.
What is the water quality of Grass Lake?
- Grass Lake in St. Lawrence County, New York has water-quality measurements published by NY DEC, shown here as reported. Maximum depth: 50.5 ft. Surface area: 341 acres.
Is Grass Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Grass Lake?
- Grass Lake has a maximum depth of 50.5 feet and an average depth of 23.6 feet. The lake covers 341 acres.
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Where this data comes from
Measurements for Grass Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.