River Swale
River Swale in Mason County, Illinois is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 193 acres.
- Area
- 193 acres
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Why River Swale 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 River Swale, 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 Illinois EPA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
River Swale is a 193-acre lake in Mason County, Illinois.
Source: EPA Water Quality Portal sampling records, Illinois EPA, last sampled recent years. Grade methodology: LakeQuality methodology.
Watch River Swale water quality
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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 River Swale
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 River Swale
Compare lakeside cabins, hotels, and vacation rentals near River Swale in Mason County, Illinois — 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 River Swale
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 193 acres |
No bathymetric survey has been published for River Swale, so its depth is not documented here.
Fishing River Swale
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Frequently asked questions about River Swale
Where is River Swale?
- River Swale is a lake in Mason County, Illinois. LakeQuality has not rated this lake (UNRATED) — no water-quality sampling on record for this lake.
What is the water quality grade for River Swale?
- River Swale in Mason County, Illinois is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 193 acres.
Is River Swale safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. River Swale is not rated for water quality — its monitoring record does not meet the evidence bar. Always check local health department advisories before swimming.
Explore River Swale across LakeQuality
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Where this data comes from
Measurements for River Swale come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.