Hiawatha Lake

Hiawatha Lake grades an F: water clarity, phosphorus, and chlorophyll-a all rate poorly, placing it among the most stressed lakes monitored in Minnesota. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

Eutrophic conditions are the baseline here: clarity drops noticeably in late summer, and dissolved oxygen near the bottom can become a concern. A maximum depth of 33 ft puts Hiawatha Lake in the middle of Minnesota's depth distribution. At 53 acres, Hiawatha Lake sits below the Minnesota median: a small water where shoreline activity has an outsized effect on water quality. Hiawatha Lake ranks 75 of 95 in Hennepin County — at the lower end of the locally monitored distribution.

Zebra mussels have been documented at Hiawatha Lake, which alters the filter-feeding balance and can paradoxically increase water clarity while disrupting the food web. The fishery includes walleye alongside the lake's other 12 documented species — a notable draw for Minnesota anglers. The lake lacks a documented public access point, so visitor use is limited. The lake has a partial ice record — 14 observed ice-outs, centered near Apr 5. 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.