South Harper Lake

South Harper Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Taylor 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 value of 32 puts South Harper Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. A maximum depth of 32 ft puts South Harper Lake in the middle of Wisconsin's depth distribution. At 72 acres, South Harper Lake sits below the Wisconsin median: a small water where shoreline activity has an outsized effect on water quality. Among the 7 graded lakes in Taylor County, South Harper Lake sits at rank 2, above the county median.

South Harper Lake has at least one documented invasive species (Chinese Mystery Snail), so boaters and anglers should observe clean-drain-dry steps when leaving the lake. The fishery includes walleye alongside the lake's other 4 documented species — a notable draw for Wisconsin anglers. Public access is available — the lake is on the Wisconsin DNR public-access list. 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.