Back to: News
May 19, 2011
Follow News

Unpredictable runoff has officials planning for worst, hoping for best

The heavy snowpack is making runoff projections particularly unpredictable this year, so emergency management officials in the Roaring Fork Valley are planning for the worst and hoping for the best.

Water experts at a State of the River meeting Wednesday night in El Jebel said that the Roaring Fork, Crystal, Fryingpan and Colorado rivers all have the potential to peak at higher than average levels because the snowpack is at 200 percent of average in parts of the Roaring Fork basin. However, only minor flooding is anticipated in areas like low-lying areas along the Crystal River, said Don Meyer, senior water resources engineer with the Colorado River District.

But all speakers had a caveat in their comments. Tim Miller of the U.S. Bureau of Reclamation said that computer models on streamflows assume average weather conditions during the melting period. If the temperatures spike for a considerable time, throw the models out the window, he said.

That point was emphasized by Dave Merritt, a member of the Colorado River District's board of directors. He said the streamflow will depend on how high the temperatures get, and for how long and how warm it remains during nights. If it heats up fast and stays warm at night, the water could come fast and furious.

Miller said the snowpack levels at three automated Snotel sites in the upper Fryingpan River Valley are the highest on record for mid-May. The bureau has reacted accordingly with the water level in Ruedi Reservoir.

"Come February, we started to bump up our releases," he said.

At first, the releases were modest because the models anticipated a fairly typical winter and spring runoff scenario. But the snowpack started to build in March, made monumental gains in April and there has been little loss in May.

The bureau has been maintaining water releases of 360 cubic feet per second (cfs) from Ruedi into the lower Fryingpan River and will do so for the foreseeable future, Miller said. The agency projects that the reservoir will fill to a level to put the boat ramps into service by mid-June and fill to capacity by early July. Releases should be kept below 800 cfs, he said. Minor flooding can occur when releases exceed that level.

The bureau also anticipates significantly higher-than-average water diversions from the Fryingpan-Arkansas Project this year. A system of diversion structures and tunnels sends water from a multitude of creeks in the upper Fryingpan River basin east to the Front Range. The annual average diversion is 54,000 acre feet. This year, it is expected to be 94,000 acre feet, Miller said.

Lake Powell, the popular reservoir in Utah, will also benefit from the central Rocky Mountain's bounty of snow. Current models indicate its water level will rise 44 feet, or 5 million acre feet, by July, Meyer said.

The runoff season in the Roaring Fork Valley this year could closely follow what occurred in 1995, according to Meyer. That high snowpack season featured drawn-out winter weather, much like this spring. The peak came late and it was much higher than average.

The Pan and Fork and Roaring Fork mobile home parks in Basalt experienced groundwater flooding that year. Both are along the Roaring Fork River, near its confluence with the Fryingpan. Water also ate into the road base of east Two Rivers Road, but the valley avoided major problems.

Pat Bingham, public information officer for Pitkin County, said emergency management agencies are "planning for the worst and hoping for the best" this runoff season. The Pitkin County and Basalt public works departments will unload sand and provide sandbags at both the riverside trailer parks in Basalt and at Elk Park in Redstone.

Bingham said officials hope the sand will be used only by residents who fear a legitimate threat to their property. They hope no one takes the opportunity to refresh their children's sand boxes, she said.

scondon@aspentimes.com


Explore Related Articles

The Aspen Times Updated May 19, 2011 06:08PM Published May 19, 2011 06:04PM Copyright 2011 The Aspen Times. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.