Amber Lake

On the LakeGrade rubric Amber Lake fails the cutoffs — a TSI of 72 and persistent algal pressure put it in the bottom tier. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

The hypereutrophic status — TSI 72 — reflects sustained heavy nutrient loading from the surrounding watershed and frequent algal pressure. Amber Lake reaches 19 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. At 182 acres, Amber Lake fits the Minnesota median for monitored lakes, with 2.2 miles of shoreline. Within Martin County's 7 graded lakes, Amber Lake ranks 5 — below the local median, though not at the bottom.

Amber Lake has no invasive species recorded in Minnesota state databases as of 2024, though prevention practices still apply at all access points. Walleye are documented at Amber Lake, one of 17 fish species on record for the lake. A documented public access point at Amber Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. The lake has a partial ice record — 18 observed ice-outs, centered near Mar 25. Multiple sampling years from Minnesota PCA volunteers and partner agencies back the grade, so the letter should hold steady absent a major watershed shift.