Almost half of the U.S. West emerged from the drought this spring, but welcome wet conditions have not fully replenished the region, scientists said Tuesday.
Hydrologists with the National Oceanic and Atmospheric Administration said deep snowpack will bring near-term relief across much of the West, but the equally deep “bathtub rings” at Lake Powell and Lake Mead reservoirs are a reminder of the long road to bringing supply and demand together in the Balance.
This winter brought copious and persistent snow from the Sierra Nevada to the Rocky Mountains, stranded residents in their homes while setting accumulation records and hauling much of the region out of drought. The amount of precipitation is impressive, but the fact that there is still snow this late in the season is perhaps less common, said Joseph Casola, director of NOAA’s western regional climate services.
“As the climate warms, the odds of such a long-lived cold anomaly over a large area like the west are going down — the chances of that happening going down and down,” Casola said.
Continued slow melt is helping reduce flood risk and delaying the onset of the region’s worst wildfire risk. Now all that means rain and snow California can offer 100% of the water being requested by cities and farms for the first time in years, and will flood farmland with excess runoff to replenish valuable groundwater.
The big question is how much relief this winter’s snow will bring to the Colorado River, which is being depleted by climate change, rising demand, and overexploitation.
A May 1 forecast of the Colorado Basin River Forecast Center said as much as 11 million acre-feet of water, or 172% of the average, could flow into Lake Powell, a vast reservoir that supplies water from the Colorado River to Arizona, Nevada, California, Mexico and dozens of tribes saves . That amount could be less depending on how much water the US Bureau of Reclamation allocates to upstream reservoirs.
According to the Bureau, 24 months operational plan, Lake Powell could rise to about 3,590 feet by mid-summer, 60 feet above its current state. That’s a level not seen since 2020.
The tough winter is taking some of the strain off the system and giving states a little more leeway to reach agreement on how to implement water cuts, said Jennifer Pitt of the National Audubon Society, which is working to restore flows throughout the basin.
When Lake Powell and Lake Mead hit record lows last summer, the US Bureau of Reclamation told states they needed to cut their water use by 15% to 30%. These cuts are still being made negotiatedwhile federal officials are considering withholding more water at the main levees.
“If everyone is involved in solving the problem and we don’t just attribute the problem to one user, one sector or one region, then maybe by spreading the pain, it hurts a little less,” Pitt said.
—————————————————-
Source link