Las Vegas Sun

April 24, 2024

Snow in Rockies not much help to Las Vegas

There's good news and bad news coming from the Rocky Mountains for Las Vegas' water situation.

The good news is last week's winter storm in the Rocky Mountains dropped snow throughout much of the range where it is most needed -- onto the mountains and valleys that feed runoff into the Colorado River, and ultimately to Lake Mead, which supplies about 90 percent of Las Vegas' drinking water.

The bad news is that it isn't enough to make a serious dent in four years of drought, and the prospects are uncertain at best for more significant snowfall this winter and spring.

John Kyle, a National Weather Service program manager in Grand Junction, Colo., said the storm gave his valley about four inches of snow. Grand Junction is already about an inch above the 21 1/2 inches of snow it averages yearly, he said.

"It's been great," he said. "We definitely need the moisture."

In the last several years of drought, Grand Junction's heaviest snowfalls have come in March and April, Kyle said.

The downside is that the ground is so dry, reservoirs so low, that only an extraordinary year will do much to turn the drought around, he said.

Observers have worse news. Although Grand Junction is above average, most of the snowfall measurements in the vast Colorado River basin, which stretches from eastern Utah and southern Wyoming across Colorado to northern Arizona and northwest New Mexico, are still below average for this time of the year.

"What it means is that for the rest of this year we will remain in drought alert," said Vince Alberta, spokesman for the Southern Nevada Water Authority.

Inflow to Lake Powell, the reservoir on the Colorado River that feeds Lake Mead, is anticipated to be 82 percent of average this year, down from the prediction of 90 percent forecast in early January, said Kelly Redmond, Desert Research Institute regional climatologist for the Western United States.

"That's kind of the effect of the lackluster January that occurred," he said. Redmond noted that much of last month was characterized by sunny blue skies over most of the Intermountain West. That's good for skiers and bike riders, but bad for the river.

"We need storms coming through on a regular basis, and they have slacked off," Redmond said.

In Wyoming the snowpack is running 80 to 85 percent of normal. In eastern Utah, it is 90 to 100 percent. In New Mexico and northern Arizona the monitors are recording 80 to 100 percent of normal, Redmond said.

Overall, that means less water than a "normal" year going into the Colorado River, he said. So while the outlook is better than the last several years, it still means more water will leave the system than went into it.

Lake levels in Powell and Mead, already at historic lows, will continue to fall, he predicted.

"It will drop more slowly, but we still still continue to drop," he said.

Kay Brothers, deputy general manager of the Southern Nevada Water Authority, agreed.

"As of today," she said Wednesday, "we've got 94 percent of the snowpack and 90 percent of the runoff."

Runoff lags the actual snowpack because the dry ground acts as a sponge, soaking up water that in other years would run into the river. "We're a little under average right now," Brothers said.

"We've got more than we've had in the past three years, but it's still less than we'd like to see," she said.

The drought has sparked water-use restrictions in Clark County, the water authority's service area. Those restrictions are expected to become more severe if the lake level, now at about 1,140 feet above sea level, drops by another 15 feet.

It already has dropped more than 70 feet during the drought. The U.S. Bureau of Reclamation estimated that the water level would fall to 1,127 feet by Jan. 1.

If it falls below 1,125 feet, the bureau could restrict water deliveries to Las Vegas and other users and prompt a new round of local use restrictions under a "drought emergency" condition. Brothers said the bureau's estimate was based on a normal year, so any deviation below normal precipitation would bring the restrictions closer.

In addition, Alberta said, with the lake level so low, a hot, windy summer in Southern Nevada could cause more evaporation on Lake Mead and bring the Las Vegas Valley closer to a drought emergency.

No matter what happens with the weather in the mountains or this valley, Alberta said, residents can expect some kind of drought restrictions to continue through next year.

"We are in a fifth year of drought," he said. "It's taken five years to get to this point. We won't solve it in one year, even if it's above normal."

/tagSun reporter (TM)Jean Reid Norman contributed to this story.

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