Foldager Slough
Foldager Slough in Day County, South Dakota is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 172 acres.
- Area
- 172 acres
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Why Foldager 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 Foldager 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 SD DANR and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Foldager Slough is a 172-acre lake in Day County, South Dakota.
Source: EPA Water Quality Portal sampling records, SD DANR, 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 Foldager 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 Foldager Slough
Compare lakeside cabins, hotels, and vacation rentals near Foldager Slough in Day County, South Dakota — 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 Foldager Slough
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 172 acres |
No bathymetric survey has been published for Foldager Slough, so its depth is not documented here.
Fishing Foldager Slough
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Frequently asked questions about Foldager Slough
Where is Foldager Slough?
- Foldager Slough is a lake in Day County, South Dakota. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for Foldager Slough?
- Foldager Slough in Day County, South Dakota is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 172 acres.
Is Foldager Slough safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Foldager 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 Foldager Slough across LakeQuality
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Where this data comes from
Measurements for Foldager Slough come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.