Long Lake
Long Lake in Montmorency County, Michigan is not rated for water quality — its monitoring record does not meet the evidence bar. Maximum depth: 80 ft. Surface area: 279.5 acres.
- Max depth
- 80 ft
- Area
- 280 acres
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Water clarity at Long Lake
Clear water. Across summers from 2018 to 2023, Long Lake averaged 4.2 m (14 ft) of visibility down into the water, so you can typically see several feet down in midsummer.
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 2.61 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.
Long Lake is a 280-acre lake in Montmorency County, Michigan with a maximum depth of 80 feet (23-foot average).
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 Long 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 Long Lake
Compare lakeside cabins, hotels, and vacation rentals near Long 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 Long Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Maximum Depth | 80 ft |
| Average Depth | 23 ft |
| Surface Area | 280 acres |
| Shoreline Length | 1.4 mi |
Fishing Long Lake
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Frequently asked questions about Long Lake
Where is Long Lake?
- Long 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 Long Lake?
- Long Lake in Montmorency County, Michigan is not rated for water quality — its monitoring record does not meet the evidence bar. Maximum depth: 80 ft. Surface area: 279.5 acres.
Is Long Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Long 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 Long Lake?
- Long Lake has a maximum depth of 80 feet and an average depth of 23 feet. The lake covers 279.5 acres.
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Where this data comes from
Measurements for Long Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.