Florence Lake

The LakeGrade rubric puts Florence Lake at a C: clarity at 9.0 ft, phosphorus readings still being added, and a TSI of 45 signal an intermediate trophic state.

Mesotrophic conditions dominate at Florence Lake: enough nutrients for a healthy fishery, not so much that algal blooms become a chronic problem. Florence Lake reaches 26 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. The lake's 135 acres and 2.2 miles of shoreline put it in the mid-range bucket — large enough for varied use, small enough that watershed inputs reach the whole basin. Within Isanti County's 19 graded lakes, Florence Lake ranks 10 — below the local median, though not at the bottom.

No invasive species are currently listed at Florence Lake — the lake remains off the Minnesota infested-waters roster. The fishery includes walleye among the lake's 15 documented species — a notable draw for Minnesota anglers. Public access is available — the lake is on the Minnesota PCA public-access list. The lake has a long ice-out record — 25 observations on file, with a median ice-out around Apr 3. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.