Feb 18, 2017

Wet winter has improved Colorado River basin's water forecast, but the drought endures

Lake Powell
United States
by
William Yardley
,
Los Angeles Times
Lake Mead reservoir and the Hoover Dam show a "bath tub ring" from low water levels in 2015. Photo: Irfan Khan, Los Angeles Times)
Lake Mead reservoir and the Hoover Dam show a "bath tub ring" from low water levels in 2015. Photo: Irfan Khan, Los Angeles Times)

 

 

California is not the only place in the West confronting startling amounts of rain and snow.

Drought conditions have declined substantially across the region in recent weeks, with heavy storms replenishing reservoirs and piling fresh powder on ski resorts.

Yet there is one place where the precipitation has been particularly welcome and could be transformative: the Colorado River basin, which provides water to nearly 40 million people across seven states.

...

While California has been climbing out of its drought — albeit the hard way, with brutal storms, mudslides and a mass evacuation ordered earlier below the damaged Oroville Dam spillway — the drought on the Colorado may never truly end.

That is because no matter how deep the snowpack may get one year — some drainages are seeing close to 200% of normal this year — the river itself functions at what its managers call a “structural deficit.” The amount of water to which cities, tribes, farmers and others have legal rights is larger than the amount that, on average, flows into the system. In addition, climate change models for the future show declining snowpack and rising temperatures, potentially leading to more evaporation.