Big Marsh Slough
Big Marsh Slough in Franklin County, Vermont is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 93 acres.
- Area
- 93 acres
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Why Big Marsh Slough 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 Marsh Slough, 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 VT DEC and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Big Marsh Slough is a 93-acre lake in Franklin County, Vermont.
Source: EPA Water Quality Portal sampling records, VT DEC, 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 Marsh Slough
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 Marsh Slough
Compare lakeside cabins, hotels, and vacation rentals near Big Marsh Slough in Franklin County, Vermont — 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 Marsh Slough
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 93 acres |
No bathymetric survey has been published for Big Marsh Slough, so its depth is not documented here.
Fishing Big Marsh Slough
Nearby Lakes in Franklin County
Frequently asked questions about Big Marsh Slough
Where is Big Marsh Slough?
- Big Marsh Slough is a lake in Franklin County, Vermont. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Big Marsh Slough?
- Big Marsh Slough in Franklin County, Vermont is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 93 acres.
Is Big Marsh Slough safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Big Marsh Slough is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Explore Big Marsh Slough across LakeQuality
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Where this data comes from
Measurements for Big Marsh Slough come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.