Lower Hay Lake vs Upper South Long Lake
Water quality, depth, fish species, and recreation comparison.
Lower Hay Lake has a higher water quality grade (A, Excellent) than Upper South Long Lake (B, Good). Both are in Crow Wing County, Minnesota.
Lower Hay Lake and Upper South Long Lake are both in Minnesota — a same-state head-to-head where the comparison comes down to lake-specific differences in depth, watershed, and monitoring history rather than the broader state-level water-quality regime. The grades are close: Lower Hay Lake (A) and Upper South Long Lake (B) are within one letter of each other on the LakeGrade rubric. The per-parameter sub-grades below will show where the small differences actually live.
With grades this close, the choice between the two lakes turns on non-water-quality factors: depth, fish species, public access, distance from home. The per-lake pages below cover all of those.
Lower Hay Lake
Crystal clear, you can see 19 ft down.
Upper South Long Lake
Murky, only visible to about 6 ft.
Side-by-Side Metrics
| Metric | Lower Hay Lake | Upper South Long Lake |
|---|---|---|
| Overall Grade | A (Excellent) | B (Good) |
| Water Clarity | 19 ft | 6 ft |
| Phosphorus | 13 µg/L | 17 µg/L |
| Chlorophyll-a (Algae) | No data | No data |
| Maximum Depth | 100 ft | 47 ft |
| Surface Area | 700.21 acres | 804.31 acres |
| Public Access | Yes | Yes |
| Fish Species | 1 | 1 |
| Trophic State | oligotrophic | mesotrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Lower Hay Lake wins on overall water quality with a Grade A versus Upper South Long Lake's Grade B. Water clarity: 19 ft vs 6 ft. For fishing diversity, Lower Hay Lake also leads with 1 species.