California Snowpack Measure Could Reveal Future of Drought

National Geographic: California Snowpack Measure Could Reveal Future of Drought
Surveyors will ski into the Sierra Nevada on Tuesday to gauge prospects for water runoff this spring.

Lisa M. Krieger
for National Geographic

An aerial view of the Sierra Mountains.

Surveyors will ski into the Sierra Nevada mountains Tuesday to perform what has become an anxiously watched rite of spring in drought-stricken California: measuring snow to determine how much water will flow to the state this year.

A critical measure of a precious resource, April’s survey will influence whether the state’s water officials declare that the drought is easing or that it persists. At stake is the fate of summer water deliveries to farms and cities.

Trailed by news media, surveyors will traverse a granite ridge on Lake Tahoe’s 6,800-foot-high (2,073-meter-high) Echo Summit—dense with fragrant pine, fir, and cedar—then drive about ten aluminum tubes into the snow to measure depth. They weigh the samples to gauge water content.

Dozens of other surveyors will be visiting more remote sites in the Sierra. Some may ski 10 to 15 miles (16 to 24 kilometers) and climb more than 5,000 feet (1,524 meters) in a single day.

The skiers, who travel in teams for the sake of safety, take turns breaking trail to conserve their strength, sometimes enlisting help from snowmobiles or helicopters.

Throughout every winter, these spots are revisited monthly to record changing conditions—but findings from the April trip are the most closely watched because that’s when snow is deepest.

April’s test is considered the most accurate snapshot of how much water is hidden within snowflakes for future use.

“April is when, historically, our snow is at its peak,” said Doug Carlson of the state Department of Water Resources. “Then it starts to peter out.”

This year’s results will be watched even more closely, as the state faces its third year of a drought that is forcing communities to drill emergency wells and farmers to fallow fields, and is threatening fish populations.

The state counts on winter snowfall to get through the rest of spring, summer, and fall. Indeed, the West’s mountain snowpack has been dubbed a “frozen reservoir,” melting into runoff that feeds the state’s rivers and nourishes farms and cities.

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