How Clean Is Mattoon Lake?
Mattoon Lake is algae-prone, with a higher bloom risk in warm months. It received a water quality grade of F (Algae-prone) based on EPA monitoring data. Water clarity (Secchi depth): 1.3 ft. Phosphorus: 294 µg/L. Chlorophyll-a (algae): 87.1 µg/L. Trophic State Index: 78.
Cleanliness Snapshot
| Metric | Mattoon Lake | Illinois avg |
|---|---|---|
| Overall Grade | F | D |
| Water Clarity (Secchi) | 1.3 ft | — |
| Phosphorus | 294 µg/L | <30 = clean |
| Chlorophyll-a (Algae) | 87.1 µg/L | <10 = clean |
| Trophic State Index | 78 | <50 = clean |
How does Mattoon Lake compare?
Mattoon Lake's grade of F falls below the Illinois state average of D. It ranks #1 of 1 lakes in Cumberland County by water quality score.
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