Alpine Lake

Alpine Lake carries a solid B grade — strong on most parameters, with measurements that hold up well across the summer season. Sub-grades cluster within a single letter of each other, which usually means the lake is in stable trophic balance rather than fighting one specific stressor.

A TSI near 41 places Alpine Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. At 65 ft of maximum depth, Alpine Lake stratifies reliably through the summer — the hypolimnion stays cooler and clearer than the surface layer suggests. Alpine Lake covers 909 acres alongside 23.9 miles of shoreline — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Alpine Lake ranks 54 of 128 in Cook County — solidly in the upper half of the local distribution.

No invasive species are currently listed at Alpine Lake — the lake remains off the Minnesota infested-waters roster. The state fisheries records do not list documented species for Alpine Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. The lake lacks a documented public access point, so visitor use is limited. Monitoring depth is thin here: the LakeGrade rubric is applied to a small number of sample years, and the grade will be revised as more data accumulates.