How Clean Is Alder Lake?
Alder Lake does not have enough monitoring data to grade. Its EPA monitoring record does not meet the evidence bar for a letter grade, so it is published unrated — that is an absence of evidence, not a poor result. The measurements below are what the record does contain. Water clarity (Secchi depth): 13.8 ft. Phosphorus: 8 µg/L. Chlorophyll-a (algae): 3.1 µg/L. Trophic State Index: 38.
Cleanliness Snapshot
| Metric | Alder Lake | Minnesota avg |
|---|---|---|
| Overall Grade | NR | C |
| Water Clarity (Secchi) | 13.8 ft | — |
| Phosphorus | 8 µg/L | <30 = clean |
| Chlorophyll-a (Algae) | 3.1 µg/L | <10 = clean |
| Trophic State Index | 38 | <50 = clean |
How does Alder Lake compare?
Alder Lake is not rated for water quality — its monitoring record does not meet the evidence bar, so it is not compared with the Minnesota state average. Multi-year monitoring data shows water quality is stable based on 2 years of records.