Published: 01/25/2023 19:57:46
LAS VEGAS — Heavy snowfalls from a series of atmospheric flows have given the beleaguered Colorado River a slightly rosier outlook.
The snow that has fallen over the mountains that feed the river in recent weeks, while not enough to fully stave off falling water levels, is expected to slow the decline at Lake Mead, according to the latest federal forecasts released last week were published. Forecasters now expect Lake Mead to be about 1,027 feet high this year, about 19 feet lower than its current level. That’s about 7 feet higher than the year-end 2023 elevation in the bureau’s forecast last month.
As for Lake Powell, the reservoir on the Utah-Arizona border is expected to end 2023 at 3,543 feet, or 16 feet higher than last month’s forecast and about 19 feet higher than its current level.
While forecasts have improved with snow cover, projected levels mean Lake Mead will remain under deficient conditions for at least a third straight year.
“I think the bigger picture is that we’re looking at some very long-term deficits along the Colorado River system,” said Steph McAfee, the state climatologist and professor at the University of Nevada, Reno. “A good year is good news. And I don’t want to belittle that. But it won’t solve the problem.”
The basin was heavily supported by a series of nine atmospheric fluxes that swept much of the west over a three-week period beginning days after Christmas. Snow cover numbers across the region are well above average, with some parts of California and Nevada currently near or exceeding 200% of the average for this time of year.
For the Colorado River, most of the runoff will be snow melting ahead of the Western Rockies, where snow cover is currently at a healthy 146% of average.
Runoff from the April-July snowmelt is expected to swell the river to 117% of its 30-year average as that snow melts and flows downstream to Lake Powell, according to the latest projections from the Colorado Basin River Forecast Center. That’s a significant increase from the 79% average the center forecast for the river last month.
The question now is whether this wet trend will continue — something that is very difficult to predict for the upper Colorado River drainage basin, McAfee said.
An encouraging sign for the entire basin was cooler-than-normal temperatures, which they say helped prevent snowpack from melting too early.
“It is quite possible that we will get more storms. It’s also possible that we couldn’t,” she said. “When it comes to the drought in the West, I’m happy to hear any good news. But maybe we just have to wait and see.”
Meanwhile, the seven states that draw water from the Colorado River are seeking agreement on how to reduce an unprecedented amount of water use along the river beginning this year. Federal officials say efforts are needed to prevent the country’s two largest reservoirs from plummeting to levels that would threaten hydroelectric power generation and water utility operations at Hoover and Glenn Canyon Dams.
Bureau of Reclamation officials have given states until the end of January to agree to a consensus proposal on how to make those cuts or risk the federal government taking those measures itself.
“Even if we had enough good years in a row to bring Lake Mead back to where it was in 1984 and 1985, we would still have to deal with this problem going forward,” McAfee said. “So we might as well figure out how to deal with that now.”