Demontreville Lake

On the LakeGrade scale Demontreville Lake grades a B, with clarity at 10.2 ft and 26 µg/L of phosphorus placing it above the Minnesota median. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

A TSI near 49 places Demontreville Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. Demontreville Lake reaches 24 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. At 157 acres, Demontreville Lake fits the Minnesota median for monitored lakes, with 3.4 miles of shoreline. Among the 83 graded lakes in Washington County, Demontreville Lake sits at rank 24, above the county median.

Zebra mussel presence at Demontreville Lake means the lake's clarity numbers carry an asterisk — filtered water is not the same as nutrient-poor water. Bass fishing is part of the appeal: the species list runs to 12, anchored by largemouth and/or smallmouth bass. A documented public access point at Demontreville Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. The grade is supported by multiple sampling years from Minnesota PCA volunteers and partner agencies, giving the letter a reasonably stable foundation.