WHY SNOWPACK MATTERS

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Last Monday, we talked a little bit about California’s water challenges and how the annual snowpack normally provides about a third of the water for California’s homes and farms as it melts into streams and reservoirs.  Because the snowpack is such bad shape, water managers are worried about the ability of California’s network of water storage and delivery systems to meet all of the needs of the state.

Snow depth is monitored throughout the winter by automated remote sensors. Then, these measurements are confirmed by hand mid April – the time of year that traditionally is when our snow is at its peak. April’s test is considered the most accurate snapshot of how much water is hidden within snowflakes for future use. Snowfall measurements taken this time of year are used for the state’s water resource allocation decisions throughout the dry season, which runs until the following winter in California. And an accurate snow survey leads to better water planning management, guides the release of water from the reservoirs, helps farmers decide what to plant, and tells city residents how aggressively to conserve.

For cities and farms across California, the latest numbers show a snowpack that is less than 10 percent of season’s average. There were many locations above 7,000 feet elevation that had no snow at all last winter forcing the state to start the dry season with about 25 percent of the typical April snow accumulation. California is not alone in its plight, however. Snowpack in southern Oregon’s Cascades Range are below average level, threatening water supply.