El Niño Not Likely to Fill Reservoirs in Colorado River Basin

(AlexandraHenryAlves/morguefile)
(AlexandraHenryAlves/morguefile)

Mark Richardson, UTAH NEWS CONNECTION- So far this winter, El Niño has not delivered the predicted rains needed to replenish the parched Colorado River Basin, conservationists say.300x250_RMB

A 15-year drought in the region – which includes Utah, Arizona, California, Colorado and other western states – has left storage reservoirs Lake Mead and Lake Powell at historic low levels. Gary Wockner, executive director of the environmental advocacy group Save the Colorado, said the river needs more than a single year of good rain to replenish the lakes.

“You need a good season to just stabilize the system,” he said. “You would need several high-precipitation years in a row to start actually refilling the reservoirs to any consequential level.”

Wockner said the U.S. Bureau of Reclamation, which manages the lakes, is projecting below-average rainfall in the lower basin through June. He said there was a lot of speculation in 2015 about how much precipitation El Niño might bring, but added that those rains just haven’t materialized. El Niño is an intermittent warm current in the south Pacific Ocean that can bring wetter-then-normal winters.

A positive benefit of the drought, Wockner said, has been a move by the river’s major water customers in California, Arizona and Nevada toward conservation.

“Lake Mead continues to be a critical problem,” he said. “And those three entities, CAP in Arizona, Metropolitan in California and the City of Las Vegas, have been working together to stop taking so much water out of Lake Mead.”

Wockner said the snowpack in the upper basin of the river in Utah and Colorado also is below average. However, he said, March and April are the snowiest months in those areas, so there still is a chance of significant precipitation this season.

River basin data is online at cbrfc.noaa.gov.