How Clean Is Lake St Croix?
Lake St Croix is a clean lake by Minnesota standards. It received a water quality grade of B (Good) based on EPA monitoring data. Water clarity (Secchi depth): 7.2 ft. Phosphorus: 32.5 µg/L. Trophic State Index: 51.
Cleanliness Snapshot
| Metric | Lake St Croix | Minnesota avg |
|---|---|---|
| Overall Grade | B | C |
| Water Clarity (Secchi) | 7.2 ft | — |
| Phosphorus | 32.5 µg/L | <30 = clean |
| Trophic State Index | 51 | <50 = clean |
How does Lake St Croix compare?
Lake St Croix's grade of B matches or beats the Minnesota state average of C. It ranks #1 of 1 lakes in Pierce County by water quality score. Multi-year monitoring data shows water quality is stable based on 5 years of records.