Lower Cullen Lake

Lower Cullen Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Crow Wing County. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

The lake's low TSI puts it in oligotrophic territory — the cleanest of the four trophic classes, but also the most vulnerable to nutrient-driven shifts. Lower Cullen Lake reaches 39 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. At 560 acres, Lower Cullen Lake fits the Minnesota median for monitored lakes, with 3.9 miles of shoreline. Lower Cullen Lake ranks 40 of 120 in Crow Wing County — solidly in the upper half of the local distribution.

Zebra mussel presence at Lower Cullen Lake means the lake's clarity numbers carry an asterisk — filtered water is not the same as nutrient-poor water. The fishery includes walleye alongside the lake's other 16 documented species — a notable draw for Minnesota anglers. A documented public access point at Lower Cullen Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. The lake has a partial ice record — 14 observed ice-outs, centered near Apr 15. 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.