Spring Lake

Spring Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Manitowoc County. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

The lake's low TSI puts it in oligotrophic territory — the cleanest of the four trophic classes, but also the most vulnerable to nutrient-driven shifts. A maximum depth of 23 ft puts Spring Lake in the middle of Wisconsin's depth distribution. At 9 acres, Spring Lake sits below the Wisconsin median: a small water where shoreline activity has an outsized effect on water quality. Among the 18 graded lakes in Manitowoc County, Spring Lake ranks 1 — in the top quartile locally.

Eurasian watermilfoil is established at Spring Lake, which can dampen recreational access and pressure the native plant community. The fishery is bass-led, with 4 documented species across the lake's records. A documented public access point at Spring Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. 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.