Lake Redstone

Lake Redstone earns an F: 92 µg/L of phosphorus and clarity at 2.0 ft signal heavy nutrient loading from the surrounding watershed. The two scored sub-grades — clarity and phosphorus — track close together, so neither one is dragging the average down.

At a TSI of 68, Lake Redstone reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. The lake's maximum depth is not yet documented in state morphometric records — context for its physical structure remains limited. At 612 acres, Lake Redstone fits the Wisconsin median for monitored lakes, with partial shoreline records. Within the 11 graded lakes of Sauk County, Lake Redstone sits at rank 9, near the bottom of the county list.

Lake Redstone has no invasive species recorded in Wisconsin state databases as of 2025, though prevention practices still apply at all access points. The state fisheries records do not list documented species for Lake Redstone, which usually reflects a lack of formal fisheries survey work rather than an empty lake. 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.