Red Willow Lake
Griggs County, WisconsinMesotrophic
Red Willow Lake is a mesotrophic lake in Griggs County, ND. Water quality is graded C based on 2 sampling years through 2025. Compared to the 1 other monitored lakes in Griggs County, Red Willow Lake ranks #2 for water quality.
Source: EPA Water Quality Portal sampling records, local state DNR records, last sampled 2025-10-23. Grade methodology: LakeGrade methodology.
Swimming Safety
Generally safe for swimming, moderate water quality
Water Quality Grade: C, Fair
Murky, only visible to about 6.4 ft. Chlorophyll-a: 6.8 µg/L. Trophic State Index: 50.
| Metric | Value | Grade |
|---|---|---|
| Water Clarity (Secchi Depth) | 6.4 ft | D |
| Phosphorus | No data | |
| Chlorophyll-a (Algae) | 6.8 µg/L | B |
| Trophic State Index (TSI) | 50 | Mesotrophic |
Moderate nutrients, good water quality
Location
County Ranking
Ranked #2 of 2 lakes in Griggs County
Nearby Lakes in Griggs County
More Wisconsin Lake Rankings
Other Grade C Lakes in Wisconsin
Mesotrophic Lakes in Wisconsin
Data Sources
Water quality data from the EPA Water Quality Portal
Grading methodology based on Metropolitan Council standards
Most recent sample: 2025-10-23
Monitoring stations: 1