Grass Lake
Grass Lake in Montmorency County, Michigan is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 632 acres.
- Area
- 632 acres
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Water clarity at Grass Lake
Moderate clarity. Across summers from 2018 to 2023, Grass Lake averaged 1.87 m (6 ft) of visibility down into the water, so visibility is middling in midsummer, which is ordinary for a productive inland lake. This lake sits close to the line between clarity classes, so treat the label as approximate and the depth reading as the real number.
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 but carries no A–F grade.
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 A–F grade on other lakes is built from phosphorus and algae measured in a laboratory, and clarity alone cannot stand in for it.
The same satellite images put summer algae here at roughly 10.26 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.
Grass Lake is a 632-acre lake in Montmorency County, Michigan.
Source: EPA Water Quality Portal sampling records, EGLE, last sampled recent years. Grade methodology: LakeQuality methodology.
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Swimming Safety
Not ratedElevated nutrients
Not rated for swimming — there is not enough monitoring data to judge this lake
Water quality measurements for Grass Lake
These readings exist but are not enough for an A–F grade — see why.
No clarity data. Trophic State Index: undefined.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | No recent samples | |
| Phosphorus | No recent samples | |
| Chlorophyll-a (Algae) | No recent samples | |
| Trophic State Index (TSI) |
Where to stay near Grass Lake
Compare lakeside cabins, hotels, and vacation rentals near Grass Lake in Montmorency County, Michigan — 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 Grass Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 632 acres |
| Shoreline Length | 1.4 mi |
The published depth figures for Grass Lake contradict each other, so no depth is shown.
Fishing Grass Lake
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Frequently asked questions about Grass Lake
Where is Grass Lake?
- Grass Lake is a lake in Montmorency County, Michigan. LakeQuality has not rated this lake (UNRATED) — no in-situ water sample; this lake is rated for water clarity from satellite observations instead.
What is the water quality grade for Grass Lake?
- Grass Lake in Montmorency County, Michigan is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 632 acres.
Is Grass Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Grass Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
How deep is Grass Lake?
- The published depth figures for Grass Lake contradict each other, so no depth is shown. The lake covers 632 acres.
Explore Grass Lake across LakeQuality
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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.