Wednesday, April 02, 2014

River runners are eager for runoff to begin

#Breckenridge, Colorado.


Whitewater rafters are salivating at the growing prospects of a long and generous runoff. Conservationists are relieved that riparian areas will be recharged after two dry years. And water managers are grateful they will be able to replenish drawn-down reservoirs.
Such is the confidence that comes with a snowpack that’s holding steady at a level considerably above average as April rolls in.
“It’s been as high as 130 percent (above average), which is great,” said Jim Ingram, owner of Aspen Whitewater Rafting, an Aspen-based company that provides commercial raft trips in the region.
Today’s snowpack is water in the late spring and summer in the Roaring Fork, Colorado and Arkansas rivers that Ingram’s business depends on.
“It’s resource for me to run on,” he said.
The past two years have been challenging for whitewater-rafting companies. A meager snowpack created particularly tough times in summer 2012. There were very few Class IV rapids in the entire state, Ingram said, and most of the rafting that could be offered was a Class II float trip.
Business was better last summer, thanks to an improved snowpack and stronger economy, Ingram said.
Savvy tourists nowadays check streamflows before booking a rafting trip just like they check snow conditions before blowing a wad on skiing vacations. Ingram said reservations are rolling in already because of the prospects of impressive flows.
“I’m looking at a good Slaughter House season,” he said, referring to the Class IV Slaughter House Falls downstream from Aspen. Based on current conditions, experience tells him the streamflow will allow his company to run the falls at least halfway through July if not the entire month.
“We’re going to have a great resource to run off of,” he said. “People grab me all the time and say, ‘You’re going to have a really good year this year.’”
The Roaring Fork River Basin ecosystem also will be a winner this year. The riparian areas and wetlands located alongside rivers and creeks will be replenished from high flows and high groundwater, said Sharon Clarke, watershed action director for the Roaring Fork Conservancy, a Basalt-based nonprofit focused on education and activism on water issues.
Those areas are like a sponge, Clarke said. The past two dry summers have wrung out the sponges. This year will replenish them.
Snowpack levels in the Roaring Fork Valley have been higher than average since the region was hit by storms in late October. The Roaring Fork River Basin as a whole is at 126 percent of average, according to the Natural Resources Conservation Service, the agency that tracks snowpack.
In the vast geographic area covered by the Roaring Fork Basin, the snowpack ranges from a low of 115 percent of average at McClure Pass to 135 percent of average at Schofield Pass in the Crystal River headwaters and 134 percent of average at Ivanhoe, near the Fryingpan River headwaters.
East of Aspen, near the headwaters of the Roaring Fork River, the snowpack is 123 percent of average.
“It’s touching where it was in 2011, but in 2011 it kept cranking,” Clarke said. That’s the spring when the snow didn’t stop coming in April and May.
Conditions were perfect in late May and June 2011 for a long, sustained runoff that didn’t peak as abruptly as feared, given the high snowpack. The Roaring Fork River peaked at about 8,000 cubic feet per second at Glenwood Springs, according to the Colorado River Basin Forecast Center, a division of the National Weather Service and National Oceanic and Atmospheric Administration.
The Roaring Fork River’s highest recorded level was 11,800 cfs at Glenwood Springs in 1995, according to the forecast center. The low was 1,870 cfs in 2012.
It’s most beneficial to the ecosystem when the runoff is high but not so high that it’s damaging, Clarke said. A high runoff flushes fine sediments out of stream beds and creates better spawning grounds and better habitat for aquatic insects, Clarke said. The higher flows also scour out holes where trout like to hang out during normal conditions, she said.
When water levels are high during runoff, trout and other fish seek out refusia habitat — secondary channels and backwaters where they can “hunker down” and stay out of the way of the fast-moving current, she said.
It’s too early in the runoff season for an accurate picture of the Roaring Fork River’s peak. That will depend on how warm it gets, for how long and when, said Eric Kuhn, director of the Colorado River District, an organization that protects western Colorado water interests. However, it appears the volume of water produced by the snowpack melting from May through July will range between 110 and 120 percent of average.
“We’re thinking it’s going to be a good year,” Kuhn said.
The big advantage of the higher volume is that water managers can build storage levels in reservoirs, he said. There should be enough water remaining after irrigation and municipal uses to store in the reservoirs. Even Lake Powell in Utah, which has been drawn down to sustained, low levels, will “bump up a little” this year, Kuhn said.
The U.S. Bureau of Reclamation has boosted releases from Ruedi Dam to above 210 cfs to make room for anticipated runoff. It increased the discharge to a higher level than usual earlier than usual. Ruedi Reservoir is currently two-thirds full. With the higher-than-average snowpack in the upper Fryingpan River Valley, prospects are great for a long boating season at high water levels on Ruedi.
Diversions from the Fryingpan-Arkansas Project from the upper Fryingpan River basin and from the Twin Lakes Canal Co. diversion system, from the upper Roaring Fork River basin, will likely benefit from the above-average snowpack. The diversion systems are limited by capacity, Kuhn said. If the snow melts at a slow and steady pace rather than during a more compact time period, they can divert water for more days.
“They’re going to be better than average,” Kuhn said.
Aspen Whitewater Rafting’s Ingram also is hoping for a “slow and steady” runoff scenario that produces a flow between 1,500 and 2,000 cfs in the Slaughter House section.
“Once you get above two grand, it gets a little scarier,” he said.
Courtesy of the Summit Daily News.