Thompson Lake
Thompson Lake in Grant County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 150 acres.
- Area
- 150 acres
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Why Thompson Lake has no grade
We grade a lake only when the monitoring record supports a letter: at least three phosphorus or chlorophyll-a samples in the last ten years, scored against EPA National Lakes Assessment thresholds for this lake’s ecoregion. For Thompson Lake, no water-quality sampling on record for this lake.
Not Rated is not an F. It is EPA Integrated Reporting Category 3 — insufficient information. The water here may be excellent or poor; nobody has measured enough of it to say. Everything below that has been measured is still reported on this page.
Sampling is run by MPCA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Thompson Lake is a 150-acre lake in Grant County, Minnesota.
Source: EPA Water Quality Portal sampling records, Minnesota DNR LakeFinder, 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 Thompson 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 Thompson Lake
Compare lakeside cabins, hotels, and vacation rentals near Thompson Lake in Grant County, Minnesota — 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 Thompson Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 150 acres |
No bathymetric survey has been published for Thompson Lake, so its depth is not documented here.
Recreation & Access
- Thompson LakePublic
Named access points in the USGS National Boat Ramps inventory, within about 3 miles. More lakes with boat ramps
Fishing Thompson Lake
Nearby Lakes in Grant County
Frequently asked questions about Thompson Lake
Where is Thompson Lake?
- Thompson Lake is a lake in Grant County, Minnesota. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Thompson Lake?
- Thompson Lake in Grant County, Minnesota is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 150 acres.
Is Thompson Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Thompson Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Are there boat ramps on Thompson Lake?
- Thompson Lake has 1 documented boat landing in the USGS National Boat Ramps inventory. Named access points include Thompson Lake.
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Where this data comes from
Measurements for Thompson Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.
Other records on this page
Lake details from Minnesota DNR LakeFinder
Named boat-access points from the USGS National Boat Ramps inventory