Snowmelt contributes a lot of water during spring

Snowmelt: Glacier melting in springtime causes high streamflows

Mountain snow fields, and glaciers, to a lesser extent, act as natural reservoirs for water in some areas, such as the western United States and Canada. These semi-permanent ice fields store precipitation from the cool season, when most precipitation falls and forms snowpacks, until the warm season when snowpacks melt and release water into rivers.

As much as 75 percent of water supplies in some western states are derived from snowmelt. As this picture of Bow River Falls, downstream from the Bow Glacier in Banff, Canada shows, spring meltwater can provide for some dramatic viewing for visiting tourists. Glacier-melt runoff often has this distinctive greenish color, often due to the suspension of very fine minerals in the water.

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