Birch Lake

Birch Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Wright County. 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 42 places Birch Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. At 52 ft of maximum depth, Birch Lake stratifies reliably through the summer — the hypolimnion stays cooler and clearer than the surface layer suggests. The lake is compact at 100 acres, with 2.0 miles of shoreline and little volume to buffer nutrient inputs. Among the 64 graded lakes in Wright County, Birch Lake ranks 1 — in the top quartile locally.

Eurasian watermilfoil is established at Birch Lake, which can dampen recreational access and pressure the native plant community. The fishery is bass-led, with 9 documented species across the lake's records. Public access is available — the lake is on the Minnesota PCA public-access list. Ice-out has been logged at Birch Lake more than two dozen times, putting the median around Apr 6 — a useful baseline for tracking climate trends. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.