Rose Lake

Rose Lake earns an F: 133 µg/L of phosphorus and clarity at 1.8 ft signal heavy nutrient loading from the surrounding watershed. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

A TSI above 70 puts Rose Lake in hypereutrophic territory: visible blooms are common, and clarity rarely climbs even in early summer. Rose Lake is a shallow lake at 11 ft maximum depth, which means it warms quickly, mixes constantly, and amplifies nutrient inputs. Rose Lake is small — 75 acres alongside 2.9 miles of shoreline — which makes it sensitive to even modest changes in watershed runoff or recreational pressure. Rose Lake ranks 79 of 83 in Washington County — at the lower end of the locally monitored distribution.

Eurasian watermilfoil is established at Rose Lake, which can dampen recreational access and pressure the native plant community. Bass fishing is part of the appeal: the species list runs to 8, anchored by largemouth and/or smallmouth bass. No formal public access is documented at Rose Lake — most use is by shoreline residents and their guests. Multiple sampling years from Minnesota PCA volunteers and partner agencies back the grade, so the letter should hold steady absent a major watershed shift.