Ray Lake

On the LakeGrade rubric, Ray Lake pulls an A: clarity at 10.0 ft and 11 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.

A TSI near 41 places Ray Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. Ray Lake reaches 27 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. The lake's 143 acres and 2.6 miles of shoreline put it in the mid-range bucket — large enough for varied use, small enough that watershed inputs reach the whole basin. Among the 133 graded lakes in Cass County, Ray Lake sits at rank 61, above the county median.

Zebra mussels have been documented at Ray Lake, which alters the filter-feeding balance and can paradoxically increase water clarity while disrupting the food web. The fishery includes walleye alongside the lake's other 17 documented species — a notable draw for Minnesota anglers. The lake lacks a documented public access point, so visitor use is limited. The lake has a partial ice record — 9 observed ice-outs, centered near Apr 11. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.