Hell’s Half Mile on the Green River devilish in 2017?
March 3, 2017
Naming Hell’s Half Mile
Hell’s Half Mile was named by explorer John Wesley Powell, whose expedition of 10 men in four wooden boats ran the rapid early in their 1869 first descent of the Green River, to the Colorado and through the Grand Canyon. Powell’s party had already wrecked one of its wooden boats in a rapid they dubbed Disaster Falls, but safely navigated Hell’s Half Mile.
Steamboat Springs — Hell's Half Mile, the infamous rapid on the Green River in Dinosaur National Monument, is expected to be heck this summer.
The Green, where it flows through Moffat County, is teeing up a season of abundance for white water paddlers and anglers in 2017. People who drew multi-day rafting permits to run the Green though the Gates of Lodore this season might want to begin a weightlifting program now. A federal water agency predicted in February that the spring runoff into Flaming Gorge Dam, just upstream from the rafting put-in, will be among the highest ever recorded. Oars men and women will need to be stout to row the rapid.
All that water has to go somewhere, and Hell's Half Mile, guarded by Lucifer's Rock, will be energized during the 2017 floating season. And, in spite of lackluster February snowfall, the Yampa River Basin is still on track to make a strong contribution to the summer river recreation season in Northwest Colorado.
Midway through the winter, the Colorado Basin River Forecast Center foresaw that the inflow snowmelt at giant Flaming Gorge Reservoir in Utah, 60 miles west of the Moffat County line by road, could be the fourth-highest on record. That prediction was based on more than double the average snowfall in parts of the huge river basin that drains the western side of the Wind River Range and the eastern side of the Wyoming Range north of Rock Springs, Wyoming.
"A very moist and mild weather pattern brought significant rain and snow to (the basin) during the first part of the month," the Forecast Center reported. "Precipitation amounts ranged between 150 to 300 percent of average, with additional increase to an already significant snowpack."
The heavy snowfall up north could translate into April through July runoff volumes on the Green River that would be 30 percent greater than average.
The Yampa River Basin has seen some of the lowest snowpack growth in Colorado since the end of January, yet the amount of water stored in the standing snow was still 121 percent of median March 3. And, when the Forecast Center ran its latest computer model projecting April through July runoff this week, it came back at 104 percent of average.
A model created the same date for the Little Snake River, just above its confluence with the Yampa, was a robust 150 percent, and the projection for the Yampa just below its confluence with the Little Snake at Deer Lodge Park was 130 percent of median.
Status of Lake Powell
Most of the water that leaves Colorado in the Yampa and Green rivers is destined for the Colorado River and Lake Powell, where the state of Colorado stores water it is obligated to send farther down the Colorado to lower basin states, such as California and Arizona.
U.S. Bureau of Reclamation officials overseeing operations at Glen Canyon Dam on the Utah/Arizona boarder reported Feb. 16 that Lake Powell was 104 feet below a full pool as of the end of January. It also reported Feb. 1 that the snowpack upstream from Lake Powell was 157 percent of median.
Based on those numbers — which didn't include the heavy February precipitation in the upper Green River Basin — officials project Lake Powell would most likely see about April-July inflow of 9.6 million acre feet of water. If that came to pass, it would represent 134 percent of the 30-year average of 7.16 million acre feet.