Upper Glaston Lake
Upper Glaston Lake in Sweet Grass County, Montana is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 357 acres.
- Area
- 357 acres
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Why Upper Glaston 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 Upper Glaston 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 Montana DEQ and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Upper Glaston Lake is a 357-acre lake in Sweet Grass County, Montana.
Source: EPA Water Quality Portal sampling records, Montana DEQ, 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 Upper Glaston 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 Upper Glaston Lake
Compare lakeside cabins, hotels, and vacation rentals near Upper Glaston Lake in Sweet Grass County, Montana — 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 Upper Glaston Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 357 acres |
No bathymetric survey has been published for Upper Glaston Lake, so its depth is not documented here.
Fishing Upper Glaston Lake
Nearby Lakes in Sweet Grass County
Frequently asked questions about Upper Glaston Lake
Where is Upper Glaston Lake?
- Upper Glaston Lake is a lake in Sweet Grass County, Montana. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Upper Glaston Lake?
- Upper Glaston Lake in Sweet Grass County, Montana is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 357 acres.
Is Upper Glaston Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Upper Glaston Lake is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
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Where this data comes from
Measurements for Upper Glaston Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.