Long Interlaken Lake

Long Interlaken Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Vilas County. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

A TSI value of 18 puts Long Interlaken Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. The lake's 65 ft maximum depth is in the upper tier for Wisconsin — deep enough for cold-water fish to find refuge in summer. Long Interlaken Lake covers 380 acres alongside partial shoreline records — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Among the 202 graded lakes in Vilas County, Long Interlaken Lake sits at rank 83, above the county median.

An invasive species record — Banded Mystery Snail — has been logged at Long Interlaken Lake; Wisconsin DNR maintains the official infested-waters list. Walleye are documented at Long Interlaken Lake, one of 6 fish species on record for the lake. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.