Big Ole Lake

Big Ole Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Itasca County. 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. The lake's 65 ft maximum depth is in the upper tier for Minnesota — deep enough for cold-water fish to find refuge in summer. The lake's 217 acres and 4.7 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 141 graded lakes in Itasca County, Big Ole Lake ranks 28 — in the top quartile locally.

No invasive species are currently listed at Big Ole Lake — the lake remains off the Minnesota infested-waters roster. The fishery includes walleye alongside the lake's other 10 documented species — a notable draw for Minnesota anglers. A documented public access point at Big Ole Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.