Huge Colorado snowpack could lead to flooding

The skiing is still good at those Colorado resorts still open. The views to the west from Denver are still of freshly snow-packed mountains. Colorado finally has some moisture. All is good, in other words. Perhaps. If it all melts at once, though, Colorado and other Western states could be in for a world of hurt.

The New York Times reported over the weekend that disaster managers throughout the West are getting very worried about the potential for flooding.

From The Times:

STEAMBOAT SPRINGS, Colo. — For all the attention on epic flooding in the Mississippi Valley, a quiet threat has been growing here in the West where winter snows have piled up on mountain ranges throughout the region.

Thanks to a blizzard-filled winter and an unusually cold and wet spring, more than 90 measuring sites from Montana to New Mexico and California to Colorado have record snowpack totals on the ground for late May, according to a federal report released last week.

Those giant and spectacularly beautiful snowpacks will now melt under the hotter, sunnier skies of June — mildly if weather conditions are just right, wildly and perhaps catastrophically if they are not.

Fear of a sudden thaw, releasing millions of gallons of water through river channels and narrow canyons, has disaster experts on edge.

“All we can do is watch and wait,” said Bob Struble, the director of emergency management for Routt County in north-central Colorado. The county’s largest community, Steamboat Springs, sits about 30 miles from the headwaters of the Yampa River, a major tributary of the Colorado River that has 17 feet of snow or more in parts of its watershed.

“This could be a year to remember,” Mr. Struble added in a recent interview in his office as snow fell again on the high country.

…

Floods kill more Americans than lightning, tornados or hurricanes in an average year, according to federal figures. And flash floods, usually associated with summer downpours, like the one that killed more than 140 people in Big Thompson Canyon in Colorado in 1976, can come as if from nowhere.

“It just takes one really sunny hot spell to get things running,” said Arthur Hinojosa, the chief of the Hydrology and Flood Operations Office with the California Department of Water Resources. “And that’s where our concern lies.”