Korth Lake

Korth Lake earns an A — every scored parameter (clarity and phosphorus) rates among the best monitored waters in Shawano County. With clarity and phosphorus scored, the sub-grades cluster within a letter of each other, pointing to stable conditions rather than one specific stressor.

A TSI near 41 places Korth Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. Korth Lake reaches 48 ft at its deepest point — typical for Wisconsin mid-sized lakes, with seasonal stratification but limited cold-water refuge. The lake is compact at 22 acres, with partial shoreline records and little volume to buffer nutrient inputs. Among the 27 graded lakes in Shawano County, Korth Lake ranks 4 — in the top quartile locally.

Zebra mussels have been documented at Korth Lake, which alters the filter-feeding balance and can paradoxically increase water clarity while disrupting the food web. Bass fishing is part of the appeal: the species list runs to 4, anchored by largemouth and/or smallmouth bass. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.