Heavy snowpack high in the Colorado Basin is starting to come down, and that's creating problems in Canyonlands National Park, where flooding from the Green River has closed a portion of the White Rim Road.
Canyonlands officials say the west side of the popular backcountry mountain bike route has been closed indefinitely due to flooding. The road is closed from the southern base of Hardscrabble Hill to the park boundary, making a complete White Rim loop-trip impossible at this time, they add.
Under the current spring runoff scenario, the closure could very well last for several weeks, they added. There are flooding issues along some portions of the White Rim when flows exceed 20,000 cfs (cubic feet per second) and the flow was approximately 23,000 cfs when the flooding occurred late last week.
As of May 10th, the Colorado Basin River Forecast Center was predicting a 50 percent chance that the Green River will peak at 46,000 cfs this year and a 90 percent chance that flows will reach at least 38,000 cfs. The last time that flows exceeded 38,000 cfs was in 1983; flows above 46,000 cfs have not occurred since 1922.
There are several variables that will determine both the peak and the duration of the high flows. Weather of course is tantamount. Warm weather and rapid snowmelt could produce very high volumes of relatively short duration. Cooler weather and a continued pattern of late-season storms could produce somewhat lower overall flows but of a longer duration.
Canyonlands National Park plans to regularly update its web page (www.nps.gov/cany) on both White Rim and boating conditions in the park. Visitors planning a trip to Canyonlands over the next few weeks should make regular checks on current conditions. You may also follow current conditions on Twitter at www.twitter.com/canyonlandsnps.