Big Salmon Lake
Big Salmon Lake in Flathead County, Montana is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 973 acres.
- Area
- 973 acres
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Why Big Salmon 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 Big Salmon 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.
Big Salmon Lake is a 973-acre lake in Flathead 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 Big Salmon 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 Big Salmon Lake
Compare lakeside cabins, hotels, and vacation rentals near Big Salmon Lake in Flathead 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 Big Salmon Lake
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 973 acres |
No bathymetric survey has been published for Big Salmon Lake, so its depth is not documented here.
Fishing Big Salmon Lake
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Frequently asked questions about Big Salmon Lake
Where is Big Salmon Lake?
- Big Salmon Lake is a lake in Flathead 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 Big Salmon Lake?
- Big Salmon Lake in Flathead County, Montana is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 973 acres.
Is Big Salmon Lake safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Big Salmon 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 Big Salmon Lake come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.