Shadow Lake

On the LakeGrade rubric, Shadow Lake pulls an A: clarity at 39.4 ft and 12 µg/L of phosphorus put it in the top bracket for Wisconsin. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

The lake's low TSI puts it in oligotrophic territory — the cleanest of the four trophic classes, but also the most vulnerable to nutrient-driven shifts. A maximum depth of 41 ft puts Shadow Lake in the middle of Wisconsin's depth distribution. The lake is compact at 44 acres, with partial shoreline records and little volume to buffer nutrient inputs. Shadow Lake ranks 7 of 27 in Waupaca County — solidly in the upper half of the local distribution.

Zebra mussels have been documented at Shadow 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 4 documented species — a notable draw for Wisconsin anglers. Public access is available — the lake is on the Wisconsin DNR public-access list. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.