Brophy Lake

On the LakeGrade rubric, Brophy Lake pulls an A: clarity at 14.4 ft and 19 µg/L of phosphorus put it in the top bracket for Minnesota. Sub-grades cluster within a single letter of each other, which usually means the lake is in stable trophic balance rather than fighting one specific stressor.

Mesotrophic conditions dominate at Brophy Lake: enough nutrients for a healthy fishery, not so much that algal blooms become a chronic problem. A maximum depth of 44 ft puts Brophy Lake in the middle of Minnesota's depth distribution. At 297 acres, Brophy Lake fits the Minnesota median for monitored lakes, with 3.5 miles of shoreline. Among the 51 graded lakes in Douglas County, Brophy Lake sits at rank 19, above the county median.

Zebra mussels have been documented at Brophy Lake, which alters the filter-feeding balance and can paradoxically increase water clarity while disrupting the food web. Walleye are documented at Brophy Lake, one of 16 fish species on record for the lake. A documented public access point at Brophy Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. Ice-out has been recorded 7 times at Brophy Lake, with a median around Apr 11. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.