Rush Island Lake

Rush Island Lake sits at the top of the Minnesota PCA grading rubric with an A, a mark reached by the cleanest lakes in Minnesota. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

Mesotrophic conditions dominate at Rush Island Lake: enough nutrients for a healthy fishery, not so much that algal blooms become a chronic problem. A maximum depth of 32 ft puts Rush Island Lake in the middle of Minnesota's depth distribution. At 297 acres, Rush Island Lake fits the Minnesota median for monitored lakes, with 3.3 miles of shoreline. Rush Island Lake ranks 47 of 141 in Itasca County — solidly in the upper half of the local distribution.

No invasive species are currently listed at Rush Island Lake — the lake remains off the Minnesota infested-waters roster. Walleye are documented at Rush Island Lake, one of 14 fish species on record for the lake. Public access is available — the lake is on the Minnesota PCA public-access list. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.