Grassy Lake
Schoolcraft County, Michigan188 acresView mapDirections
No nutrient or algae sampling on record from EGLE for this lake.
- 36 ft max depth
Grassy Lake in Schoolcraft County, Michigan has water-quality measurements published by EGLE, shown here as reported. Maximum depth: 36 ft. Surface area: 188.1 acres.
Water clarity at Grassy Lake
Moderate clarity. Across summers from 2018 to 2023, Grassy Lake averaged 2.34 m (8 ft) of visibility down into the water, so visibility is middling in midsummer, which is ordinary for a productive inland lake.
Nobody has taken a water sample here that we can find. Michigan's environmental agency measures clarity on lakes like this one from satellite images instead, which is why this page reports how clear the water is and no phosphorus or algae readings.
Clear is not the same as clean. A lake can be easy to see through and still carry high nutrient levels, and a naturally tea-stained lake can be perfectly healthy. The nutrient and algae readings on other lakes come from phosphorus and chlorophyll-a measured in a laboratory, and clarity alone cannot stand in for them.
The same satellite images put summer algae here at roughly 7.66 micrograms per litre. Estimating algae from orbit is far less exact than measuring clarity, so that figure is worth knowing and is not part of any rating.
Grassy Lake is a 188-acre lake in Schoolcraft County, Michigan with a maximum depth of 36 feet (13-foot average).
Source: EPA Water Quality Portal sampling records, EGLE. Methodology: how these readings are compared.
What Grassy Lake is good for
From access and monitoring records, not editorial picks.
- Deep water36 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 Grassy Lake is safe to swim in today is a call for the Michigan Department of Environment, Great Lakes, and Energy (EGLE) and the county health department, who post current advisories. LakeQuality does not issue swimming clearances.
Water quality measurements for Grassy Lake
These are the measurements EGLE publishes for Grassy 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 Grassy Lake
Answers come straight from the public measurements and survey records on this page.
Lake Details
Max depth
36 ft
Average depth
13 ft
Surface area
188 acres
Shoreline
1 mi
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Fishing Grassy Lake
Nearby Lakes in Schoolcraft County
Frequently asked questions about Grassy Lake
Where is Grassy Lake?
- Grassy Lake is a lake in Schoolcraft County, Michigan. Its water-quality measurements are published by EGLE and shown on this page as reported.
What is the water quality of Grassy Lake?
- Grassy Lake in Schoolcraft County, Michigan has water-quality measurements published by EGLE, shown here as reported. Maximum depth: 36 ft. Surface area: 188.1 acres.
Is Grassy Lake safe to swim in?
- Nutrient and algae readings are not a swimming clearance. Check local advisories before you swim.
How deep is Grassy Lake?
- Grassy Lake has a maximum depth of 36 feet and an average depth of 13 feet. The lake covers 188.1 acres.
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Where this data comes from
Measurements for Grassy Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.