How Clean Is Decatur Lake?
Decatur Lake is nutrient-rich, with elevated phosphorus and algae. Its nutrient and algae readings come from EPA monitoring data. Water clarity (Secchi depth): 1.3 ft. Phosphorus: 103 µg/L. Chlorophyll-a (algae): 25 µg/L. Trophic State Index: 69.
Cleanliness Snapshot
| Metric | Decatur Lake | Illinois avg |
|---|---|---|
| Water Clarity (Secchi) | 1.3 ft | — |
| Phosphorus | 103 µg/L | <30 = clean |
| Chlorophyll-a (Algae) | 25 µg/L | <10 = clean |
| Trophic State Index | 69 | <50 = clean |
How does Decatur Lake compare?
Decatur Lake's readings match or beat the Illinois state average. It ranks #1 of 1 lakes in Macon County on nutrient and algae readings.
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