Marion Lake vs Preston Lake
Water quality, depth, fish species, and recreation comparison.
Marion Lake and Preston Lake read the same on nutrients and algae. Both are in Minnesota.
Both Marion Lake and Preston Lake sit in Minnesota. A same-state comparison strips out the state-level water-quality regime as a variable: any differences in the readings here are about the lakes themselves, not the agencies sampling them. These two sit close on the readings, Marion Lake versus Preston Lake. The deciding factors for a recreational visitor are likely physical (depth, access, fish species) rather than water-quality differences.
With readings 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.
Marion Lake
No clarity data.
Preston Lake
Murky, only visible to about 5 ft.
Side-by-Side Metrics
| Metric | Marion Lake | Preston Lake |
|---|---|---|
| Water Clarity | No data | 5 ft |
| Phosphorus | 71 µg/L Better | 222 µg/L |
| Chlorophyll-a (Algae) | 73 µg/L | 39.2 µg/L Better |
| Maximum Depth | 15.2 ft Better | 11 ft |
| Surface Area | 520 acres | 655 acres |
| Public Access | Yes | Yes |
| Fish Species | 13 | 13 |
| Trophic State | eutrophic | eutrophic |
A green ✓ marks the better value for that metric (lower phosphorus / chlorophyll = cleaner; higher Secchi / depth / species count = better). Surface area and trophic state carry no tick — a bigger lake is not a better lake.
Swap a lake
Compare Marion Lake or Preston Lake against a different lake.
Verdict
Both lakes earn the same Grade F. The tiebreakers come down to what you want from the lake. Marion Lake matches its peer on species count.
Source: EPA National Aquatic Resource Surveys, 2026.