Hicklin Lake is a small lake in the White Center census-designated place of King County, Washington, near Evergreen High School, Cascade Middle School, and Dick Thurnau Park (Lakewood Park).

However, in the 1960s, this wetland was replaced with a parking lot, and the main inflow to the lake is now stormwater pipes.

This untreated stormwater has brought heavy metals, phosphorus, and fecal coliform bacteria to the lake.

[2][3] King County has routinely treated the lake with alum to reduce populations of blue-green algae, but this has failed to work long-term.

[5] The islands contain native vegetation, and it was hoped that microbes in their roots would consume phosphorus (a major contributor to algal blooms and eutrophication).