Otter Tail River Lake

Otter Tail River Lake carries a solid B grade — strong on most parameters, with measurements that hold up well across the summer season. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

The lake sits in the mesotrophic zone — the band where most well-managed Minnesota lakes fall. At 55 ft of maximum depth, Otter Tail River Lake stratifies reliably through the summer — the hypolimnion stays cooler and clearer than the surface layer suggests. At 313 acres, Otter Tail River Lake fits the Minnesota median for monitored lakes, with 9.1 miles of shoreline. Within Otter Tail County's 97 graded lakes, Otter Tail River Lake ranks 59 — below the local median, though not at the bottom.

Zebra mussels have been documented at Otter Tail River Lake, which alters the filter-feeding balance and can paradoxically increase water clarity while disrupting the food web. The fishery is panfish-dominated — bluegill, crappie, and sunfish among the 3 species documented for the lake. A documented public access point at Otter Tail River Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.