Dutch Hollow Lake

On the LakeGrade rubric, Dutch Hollow Lake pulls an A: clarity at 49.2 ft and 13 µg/L of phosphorus put it in the top bracket for Wisconsin. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

Trophically, Dutch Hollow Lake reads as oligotrophic — nutrient-poor, clear, and ecologically more sensitive to disturbance than richer lakes. A maximum depth of 38 ft puts Dutch Hollow Lake in the middle of Wisconsin's depth distribution. The lake's 172 acres and partial shoreline records put it in the mid-range bucket — large enough for varied use, small enough that watershed inputs reach the whole basin. Within Sauk County's 11 graded waters, Dutch Hollow Lake sits at rank 1, near the top of the local distribution.

Eurasian watermilfoil is established at Dutch Hollow Lake, which can dampen recreational access and pressure the native plant community. Walleye are documented at Dutch Hollow Lake, one of 2 fish species on record for the lake. Public access is available — the lake is on the Wisconsin DNR public-access list. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.