Hill Slough Lake

Hill Slough Lake earns a C — middle-of-the-pack water quality, with one or two parameters dragging the average down from a stronger grade. With clarity and phosphorus scored, the sub-grades cluster within a letter of each other, pointing to stable conditions rather than one specific stressor.

At a TSI of 57, Hill Slough Lake 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. The lake's surface area is not consistently recorded across state datasets — physical context remains partial. Hill Slough Lake sits at rank 7 of 11 in Sauk County, in the lower half of the local distribution.

Hill Slough Lake 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 Hill Slough Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.