Lake St Croix vs Pool
Water quality, depth, fish species, and recreation comparison.
Lake St Croix and Pool both received the same overall water quality grade of B (Good). Both are in Minnesota.
Lake St Croix and Pool 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. These two are within a letter of each other on the rubric — Lake St Croix (B) versus Pool (B). The deciding factors for a recreational visitor are likely physical (depth, access, fish species) rather than water-quality differences.
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.
Lake St Croix
Moderate clarity, visible to about 7.2 ft.
Pool
Murky, only visible to about 5.9 ft.
Side-by-Side Metrics
| Metric | Lake St Croix | Pool |
|---|---|---|
| Overall Grade | B (Good) | B (Good) |
| Water Clarity | 7.2 ft | 5.9 ft |
| Phosphorus | 32.5 µg/L | 31.1 µg/L |
| Chlorophyll-a (Algae) | No data | No data |
| Maximum Depth | 78 ft | 78 ft |
| Surface Area | 8,393 acres | 8,393 acres |
| Public Access | No | No |
| Fish Species | 36 | 36 |
| Trophic State | eutrophic | eutrophic |
Bold value = better for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better).
Verdict
Both lakes earn the same Grade B. The tiebreakers come down to clarity (Lake St Croix: 7.2 ft, Pool: 5.9 ft) and what you want from the lake. Lake St Croix matches its peer on species count.
Source: EPA National Aquatic Resource Surveys, 2026.