Long Lost Lake

Long Lost Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Clearwater County. Sub-grades cluster within a single letter of each other, which usually means the lake is in stable trophic balance rather than fighting one specific stressor.

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. At 63 ft of maximum depth, Long Lost Lake stratifies reliably through the summer — the hypolimnion stays cooler and clearer than the surface layer suggests. Long Lost Lake covers 539 acres alongside 14.3 miles of shoreline — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Among the 40 graded lakes in Clearwater County, Long Lost Lake ranks 8 — in the top quartile locally.

Long Lost Lake has no invasive species recorded in Minnesota state databases as of 2025, though prevention practices still apply at all access points. The fishery includes walleye alongside the lake's other 11 documented species — a notable draw for Minnesota anglers. A documented public access point at Long Lost Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. The lake has a partial ice record — 12 observed ice-outs, centered near Apr 19. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.