Vermilion Lake

Vermilion Lake earns a D — measurements through 2024 show persistent nutrient pressure that limits clarity through the summer.

At a TSI of 57, Vermilion Lake reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. The lake's maximum depth is not yet documented in state morphometric records — context for its physical structure remains limited. The lake's surface area is not consistently recorded across state datasets — physical context remains partial. Within the 187 graded lakes of St. Louis County, Vermilion Lake sits at rank 168, near the bottom of the county list.

An invasive species record — spiny waterflea — has been logged at Vermilion Lake; Minnesota PCA maintains the official infested-waters list. The state fisheries records do not list documented species for Vermilion Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. Public access is available — the lake is on the Minnesota PCA public-access list. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.