
Lobster Lake vs Red Rock Lake
Water quality, depth, fish species, and recreation comparison.
Lobster Lake reads lower on nutrients and algae than Red Rock Lake. Both are in Douglas County, Minnesota.
Lobster Lake and Red Rock 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 readings are meaningfully apart: Lobster Lake carries clearly lower phosphorus and chlorophyll-a readings than Red Rock Lake. A spread that wide reflects real underlying differences, in watershed inputs, depth profiles, or monitoring rigor.
For a recreational visitor, the wider gap in the readings is decisive: Lobster Lake has the lower nutrient and algae numbers. For a researcher, the gap is the interesting part: what is different about the two watersheds, and which of those differences is mutable?
Lobster Lake
Good clarity, visible to about 13 ft.
Red Rock Lake
Murky, only visible to about 3.6 ft.
Side-by-Side Metrics
| Metric | Lobster Lake | Red Rock Lake |
|---|---|---|
| Water Clarity | 13 ft Better | 3.6 ft |
| Phosphorus | 20.5 µg/L Better | 55 µg/L |
| Chlorophyll-a (Algae) | 3.6 µg/L Better | 33.7 µg/L |
| Maximum Depth | 65 ft Better | 22 ft |
| Surface Area | 1,334 acres | 904 acres |
| Public Access | Yes | Yes |
| Fish Species | 18 Better | 13 |
| Trophic State | mesotrophic | 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 Lobster Lake or Red Rock Lake against a different lake.
Verdict
Lobster Lake reads lower on nutrients and algae than Red Rock Lake. Water clarity: 13 ft vs 3.6 ft. For fishing diversity, Lobster Lake also leads with 18 species.
Source: EPA National Aquatic Resource Surveys, 2026.