Crooked Lake

On the LakeGrade scale Crooked Lake grades a B, with clarity at 8.0 ft and 17 µg/L of phosphorus placing it above the Wisconsin median. Clarity is the limiting factor — phosphorus is reasonable but suspended particles or algal cells keep water transparency below Wisconsin norms.

A TSI near 46 places Crooked Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. A maximum depth of 16 ft puts Crooked Lake in the middle of Wisconsin's depth distribution. At 51 acres, Crooked Lake sits below the Wisconsin median: a small water where shoreline activity has an outsized effect on water quality. Crooked Lake ranks 21 of 45 in Waukesha County — solidly in the upper half of the local distribution.

Crooked 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 is bass-led, with 3 documented species across the lake's records. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.