An 'average wet year' reported
Published Thursday, June 8, 2017 3:02 pm
Regional water managers reporting at the annual State of the River meeting in Montrose on May 31 see a fully adequate water year ahead, one which was characterized as "an average wet year."
Presenting an update on several local drainages, Bob Hurford, engineer for state water division 4, reported that the Uncompahgre River drainage "has a big snow pack."
"There is still a lot of snow in the San Juans," he said. The Uncompahgre drainage had 118 percent of snow water equivalent in its seasonal peak snowpack this year. The river's flows have reached almost 600 cubic feet per second (cfs) and are expected to reach over 1,000 cfs this runoff season, he reported.
"Ridgway Reservoir will be full by the 4th of July," he said.
The Paonia Reservoir drainage had 115 percent of snow water equivalent at its seasonal peak this year, it was reported. The North Fork River reached 3,000 cfs peak flow at Somerset in March.
At Columbine Pass on the Uncompahgre Plateau, streams that feed creek drainages into the Gunnison River west of Delta have experienced 143 percent of snow water equivalent in peak level snowpack.
In the Upper Gunnison Basin, the Blue Mesa Reservoir drainage also had 143 percent snow water equivalent in peak snowpack levels.
All indications for the coming months are good. Variables from soil moisture content to weather forecasts are looking favorable for the water year.
It was reported that 65 to 70 percent of the water flowing into Lake Powell comes from the Colorado River Basin. This year those flows have been augmented by an exceptionally large water supply coming out of Flaming Gorge Reservoir.
Ryan Christianson of the Bureau of Reclamation characterized this water year as, "An average wet year."
Stream flow targets for water releases from the Aspinall Unit into the Gunnison River are for 14,040 cfs at Whitewater for two consecutive days, and for a 20-day average of 8,070 cfs, the half-bank-full level.
Target peak flows in the Black Canyon are 6,427 cfs for a 24-hour duration.
Eric Kuhn of the Colorado River District, sponsor for the State of the River presentation, noted that 80 percent of the Colorado River Basin is high desert terrain. Basin storage capacity equals four times the annual river flow.
By contrast, he said, the Columbia River Basin encompasses approximately the same area as the Colorado River Basin does, but it has 17 times the annual river flow of the Colorado River Basin and only a fraction of its flow is in storage.
Kuhn characterized the current water picture as "four good years in a row."