Whitefish Lake: The Deepest Cold Water in the Valley
Near Whitefish, Montana
Whitefish Lake is one of the cleanest large lakes in Montana. It covers about three thousand acres and reaches depths of more than two hundred feet in places. The lake sits in a glacially carved basin gouged out during the last ice age, when glaciers moving southward from Canada scraped the mountains and deposited deep depressions across the Flathead Valley.
The lake's water is cold, clear, and fed by streams draining the mountains around it. The town has never used the lake as a municipal water supply, which has spared it many of the inputs that degrade other lakes. The Whitefish Lake Institute was established to monitor and protect the lake's water quality, running long-term measurements of temperature, clarity, and biological indicators to detect changes before they become crises.
The lake is classified as oligotrophic, meaning it is nutrient-poor and supports relatively little algae, which is exactly the condition that keeps the water clear. The town's name comes from the fish rather than the water's color. Whitefish, mainly the native mountain whitefish, were abundant enough in the lake that the town took its name from them.
Lake whitefish were introduced later and are now common too. Bull trout, a native species that has declined sharply across the West, are also present in the lake and its tributary streams. Bull trout require extremely cold, clean water and are considered a species of concern in Montana.
The health of Whitefish Lake is directly tied to their persistence in this part of the watershed.
