Longtime state hydrological engineer Matt Lindon says the Provo River will have moved 130,000 acre-feet of water by September, the end of Utah’s water year.
The Weber River will have moved nearly the same amount.
Hydrologists like Lindon can make those predictions after Utah’s snowpack melt was complete June 13, per the U.S. Department of Agriculture’s SNOTEL data.
An acre-foot describes how much could cover a football field with one foot of water—that’s 326,000 gallons or half an Olympic-sized swimming pool.
“An acre-foot can support two to four houses with two to four people in each house, so it's a substantial amount of water,” Lindon said.
Each river contains about 130,000 acre feet of water, but they’re shrinking by about 350 acre-feet each year.
“You scale that out over 100 years, and we're losing 70,000 acre-feet,” he said. “That's 250,000 houses. That's about enough water for a million people.”
Despite the past two water years holding strong, Lindon said Utah is facing drought in the long run.
“Last year, the Great Salt Lake went up five feet. And that was wonderful, but it went down three from evaporation,” he said. “This year, it goes up three, and it'll probably lose that three. So realistically, even with these good years, we're only holding our own.”
Utah’s snowpack peaked at about 120% of normal this year.
Lindon estimates about 80% of Utah’s water goes to natural vegetation, and 80% of what remains becomes groundwater. That leaves 4% of the state’s water to fill lakes and reservoirs.