Middle Slough
Middle Slough in Calhoun County, Illinois is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 124 acres.
- Area
- 124 acres
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Why Middle 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 Middle 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 Illinois EPA and volunteer programs, and published through the EPA Water Quality Portal. Read the full grading methodology.
Middle Slough is a 124-acre lake in Calhoun County, Illinois.
Source: EPA Water Quality Portal sampling records, Illinois EPA, last sampled recent years. Grade methodology: LakeQuality methodology.
Watch Middle Slough 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 Middle 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 Middle Slough
Compare lakeside cabins, hotels, and vacation rentals near Middle Slough in Calhoun 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 Middle Slough
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Lake Details
| Characteristic | Value |
|---|---|
| Surface Area | 124 acres |
No bathymetric survey has been published for Middle Slough, so its depth is not documented here.
Fishing Middle Slough
Nearby Lakes in Calhoun County
Frequently asked questions about Middle Slough
Where is Middle Slough?
- Middle Slough is a lake in Calhoun 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 Middle Slough?
- Middle Slough in Calhoun County, Illinois is not rated for water quality — its monitoring record does not meet the evidence bar. Surface area: 124 acres.
Is Middle Slough safe to swim in?
- Not rated for swimming — there is not enough monitoring data to judge this lake. Middle 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 Middle Slough across LakeQuality
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Where this data comes from
Measurements for Middle Slough come from the EPA Water Quality Portal. Per-sample source details are not recorded for this lake.