Shields Lake

Shields Lake earns an F: phosphorus readings still being added and clarity at 2.5 ft signal heavy nutrient loading from the surrounding watershed. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

A TSI in the eutrophic range signals a lake doing what nutrient-loaded waters do — supporting an active algal community at the cost of clear water. The lake bottoms out at 42 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. At 940 acres, Shields Lake fits the Minnesota median for monitored lakes, with 9.0 miles of shoreline. Within the 12 graded lakes of Rice County, Shields Lake sits at rank 10, near the bottom of the county list.

Shields Lake carries an invasive watermilfoil record — boat-launch decontamination and shoreline care matter more here than at uninfested lakes. The fishery includes walleye alongside the lake's other 17 documented species — a notable draw for Minnesota anglers. A documented public access point at Shields Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. Ice-out has been logged at Shields Lake more than two dozen times, putting the median around Apr 5 — a useful baseline for tracking climate trends. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.