Langdon Lake

Langdon Lake earns an F: phosphorus readings still being added and clarity at 1.5 ft signal heavy nutrient loading from the surrounding watershed. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

A TSI above 70 puts Langdon Lake in hypereutrophic territory: visible blooms are common, and clarity rarely climbs even in early summer. Langdon Lake reaches 38 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. Langdon Lake covers 143 acres alongside 2.1 miles of shoreline — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Within the 95 graded lakes of Hennepin County, Langdon Lake sits at rank 76, near the bottom of the county list.

Eurasian watermilfoil has been documented at Langdon Lake, requiring shoreline management to keep dense mats from crowding native vegetation. The fishery is panfish-dominated — bluegill, crappie, and sunfish among the 8 species documented for the lake. The lake lacks a documented public access point, so visitor use is limited. The lake has a partial ice record — 5 observed ice-outs, centered near Mar 31. 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.