By Blake Apgar
Projections from the U.S. Bureau of Reclamation show Lake Mead is in danger of dropping low enough to trigger its first federally declared water shortage next year.
A study this month from the Bureau of Reclamation, based on the most probable inflow, shows Lake Mead, now at 1,085 feet, could end the year below 1,070 feet.
If projections in August show the lake level dropping below 1,075 feet at that time, a federal shortage will be declared.
“I think we are as close as we’ve ever been to seeing that determination,” said Colby Pellegrino, deputy general manager of resources for the Southern Nevada Water Authority.
That means fixing leaks, setting water clocks, fixing sprinklers that spray into the street and getting rid of unnecessary grass.
“Those little things do make a really big difference in our overall water usage,” Pellegrino said.
It’s still possible that a water shortage could be avoided through a combination of an abundance of wintry weather in the Rockies and conservation.
A shortage would reduce Southern Nevada’s allocation of 300,000 acre-feet of water from the Colorado River by 13,000 acre-feet. That would still leave it with more available water than the approximately 250,000 acre-feet the region consumed last year, according to the water authority.
One acre-foot of water is about what two Las Vegas Valley homes use over the course of 16 months.
About 90 percent of Southern Nevada’s water comes from Lake Mead.
Dry conditions, little snow
Projections of lower water levels in Lake Mead are in part due to projections that the Colorado River will experience a significantly lower-than-average flow of melted snow from the Colorado Rockies this year.
As of Monday, the snowpack that eventually flows into the Colorado River was 28 percent below average, according to a report from the Bureau of Reclamation.
“Right now things are looking pretty bad,” said Warren Turkett, a natural resource analyst for the Colorado River Commission of Nevada. “It’s been really dry.”
A below-average snowpack, coupled with dry conditions, means runoff from the Rockies into the river is expected to be about 53 percent of average, he said.
Dry soil acts like a sponge, soaking up runoff before it can flow into the river.
Last year, the Rockies had an above-average snowpack, but dry conditions resulted in a runoff that was only about 54 percent of average, Turkett said.
Since 2000, the first year of the drought, there have been 16 years when runoff into the Colorado River was below the historic average, he said.
So far this water year the upper basin of the Colorado River has only experienced 64 percent of average precipitation.
“Last summer was incredibly dry and hot as well, so the ground really dried out prior to this water year,” Turkett said. Water years run from October to September.
Still, Turkett said, a lot can happen between now and when runoff season begins, usually in April.