Green Lake

The LakeGrade rubric puts Green Lake at a C: clarity at 9.0 ft, phosphorus readings still being added, and a TSI of 45 signal an intermediate trophic state. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

The lake sits in the mesotrophic zone — the band where most well-managed Minnesota lakes fall. A maximum depth of 20 ft puts Green Lake in the middle of Minnesota's depth distribution. At 160 acres, Green Lake fits the Minnesota median for monitored lakes, with 4.0 miles of shoreline. Within St. Louis County's 215 graded lakes, Green Lake ranks 111 — below the local median, though not at the bottom.

No invasive species are currently listed at Green Lake — the lake remains off the Minnesota infested-waters roster. The state fisheries records do not list documented species for Green Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. No formal public access is documented at Green Lake — most use is by shoreline residents and their guests. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.