Big Cedar Lake

On the LakeGrade rubric, Big Cedar Lake pulls an A: clarity at 14.4 ft and 16 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.

A TSI near 41 places Big Cedar Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. Big Cedar Lake is unusually deep for Wisconsin at 105 ft, which buffers the lake against summer warming and helps the deep water stay oxygenated. The lake's 937 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. Big Cedar Lake sits at rank 11 of 15 in Washington County, in the lower half of the local distribution.

Big Cedar Lake is on the Wisconsin infested-waters list for zebra mussels — boaters should follow clean-drain-dry protocols when moving gear to or from 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. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.