How Clean Is Lake St Louis?
Lake St Louis does not have enough monitoring data to describe. It does not have enough recent summer sampling for a nutrient or algae figure. That means the measurements are missing, not that the water is poor. Everything the monitoring record does contain is below. Water clarity (Secchi depth): 2.7 ft. Phosphorus: 50 µg/L. Chlorophyll-a (algae): 74.3 µg/L. Trophic State Index: 65.
Cleanliness Snapshot
| Metric | Lake St Louis | Missouri avg |
|---|---|---|
| Water Clarity (Secchi) | 2.7 ft | — |
| Phosphorus | 50 µg/L | <30 = clean |
| Chlorophyll-a (Algae) | 74.3 µg/L | <10 = clean |
| Trophic State Index | 65 | <50 = clean |
How does Lake St Louis compare?
Lake St Louis has too little recent summer sampling to compare, so it is not compared with the Missouri state average. Multi-year monitoring data shows water quality is declining based on 5 years of records.
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