Ml-Garrison Lake

On the LakeGrade scale Ml-Garrison Lake grades a B, with clarity at 12.5 ft and 26 µg/L of phosphorus placing it above the Minnesota median. 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. Ml-Garrison Lake reaches 42 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. With 128,250 acres of surface and 105.5 miles of shoreline, Ml-Garrison Lake is a large water by Minnesota standards — recreational pressure is spread across a long shoreline. Ml-Garrison Lake ranks 26 of 53 in Aitkin County — solidly in the upper half of the local distribution.

Ml-Garrison Lake is on the Minnesota infested-waters list for zebra mussels — boaters should follow clean-drain-dry protocols when moving gear to or from the lake. Muskie are on the species list at Ml-Garrison Lake, alongside the lake's 21 other documented fish. Public access is available — the lake is on the Minnesota PCA public-access list. The lake has a long ice-out record — 105 observations on file, with a median ice-out around Apr 25. Multiple sampling years from Minnesota PCA volunteers and partner agencies back the grade, so the letter should hold steady absent a major watershed shift.