Dairyland Reservoir

Dairyland Reservoir earns an F: phosphorus readings still being added and clarity at 1.4 ft signal heavy nutrient loading from the surrounding watershed. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

The hypereutrophic status — TSI 73 — reflects sustained heavy nutrient loading from the surrounding watershed and frequent algal pressure. The lake's 70 ft maximum depth is in the upper tier for Wisconsin — deep enough for cold-water fish to find refuge in summer. At 1,870 acres, Dairyland Reservoir is one of the larger lakes in Rusk County, with partial shoreline records supporting multiple distinct use patterns. Within the 12 graded lakes of Rusk County, Dairyland Reservoir sits at rank 11, near the bottom of the county list.

Eurasian watermilfoil has been documented at Dairyland Reservoir, requiring shoreline management to keep dense mats from crowding native vegetation. Walleye are documented at Dairyland Reservoir, one of 8 fish species on record for the lake. 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.