Lottie Lake

On the LakeGrade rubric, Lottie Lake pulls an A: clarity at 16.1 ft and 16 µg/L of phosphorus put it in the top bracket for Minnesota. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

A TSI near 40 places Lottie Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. Lottie Lake reaches 31 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. The lake is compact at 46 acres, with 2.2 miles of shoreline and little volume to buffer nutrient inputs. Among the 51 graded lakes in Douglas County, Lottie Lake ranks 10 — in the top quartile locally.

Zebra mussel presence at Lottie Lake means the lake's clarity numbers carry an asterisk — filtered water is not the same as nutrient-poor water. Walleye are documented at Lottie Lake, one of 14 fish species on record for the lake. The lake lacks a documented public access point, so visitor use is limited. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.