Arrowhead Lake

Arrowhead Lake carries a solid B grade — strong on most parameters, with measurements that hold up well across the summer season. With clarity and phosphorus scored, the sub-grades cluster within a letter of each other, pointing to stable conditions rather than one specific stressor.

Eutrophic conditions are the baseline here: clarity drops noticeably in late summer, and dissolved oxygen near the bottom can become a concern. Arrowhead Lake is a shallow lake at 13 ft maximum depth, which means it warms quickly, mixes constantly, and amplifies nutrient inputs. At 296 acres, Arrowhead Lake fits the Minnesota median for monitored lakes, with 4.1 miles of shoreline. Arrowhead Lake ranks 93 of 120 in Crow Wing County — at the lower end of the locally monitored distribution.

Zebra mussels have been documented at Arrowhead Lake, which alters the filter-feeding balance and can paradoxically increase water clarity while disrupting the food web. The fishery includes walleye among the lake's 16 documented species — a notable draw for Minnesota anglers. No formal public access is documented at Arrowhead Lake — most use is by shoreline residents and their guests. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.