Colorado River crisis won’t stop explosive growth in Las Vegas, officials say

It’s a no-brainer for many: As the outer boundaries of the Las Vegas Valley blur and thousands of homes pop up where only desert used to be, the bathtub ring around Lake Mead seems to only deepen.

An ever-growing desert metropolis and worsening mega-drought seem like a recipe for disaster, and the doom-and-gloom headlines about the Colorado River seem to only confirm people’s worst fears.

But ask Colby Pellegrino, deputy general manager of resources at the Southern Nevada Water Authority, and Las Vegans might walk away with more hope that future generations will be able to enjoy living in the city like they do.

“Our goal is to always be ahead from an adaptation standpoint,” Pellegrino said in an interview. “The key to new development and continuing to diversify and grow is, what is the water footprint of that growth? That’s where all of the hard things that we’ve done — our evaporative cooling moratorium, no turf in new homes — all of that is ensuring that we shrink down the water footprint as we continue to grow our community.”

Pellegrino presented updated water use projections to the water authority board last month, taking into account scenarios that vary based on whether the agency can meet its conservation goals and poor conditions seen these last few years when it comes to declining flows down the Colorado River.

The bottom line? If the valley’s already aggressive — and sometimes controversial — conservation measures get even more aggressive by 2035, Las Vegas could be on pace to stay within the boundaries of its permanent water supply through 2075.

Negotiations could have big sway

The water authority’s projections account for adding anywhere between 987,000 and 1.82 million residents to Clark County by 2075, as predicted in this year’s estimates from UNLV’s Center for Business and Economic Research.

But, as the report emphasizes, water managers could be left with difficult questions if “the economy, climate, population and water use variability” drive demand up, conservation goals prove to be unattainable or both.

One of those uncertainties is the stalling negotiations between the seven Colorado River Basin states that must come to a resolution by Feb. 14, according to a deadline set by the Bureau of Reclamation. At a December conference in Las Vegas, the seven U.S. states that share the river appeared to be no closer to striking a deal.

Further cuts to Nevada’s 300,000 acre-foot share of the river seem certain, which is why the water authority increased expected reductions in Colorado River water this year to 50,000 acre-feet, Pellegrino said.

That’s not because Nevada expects to be on the losing end of negotiations, however, Pellegrino said.

“There is an art to not negotiating against yourself in a public document,” Pellegrino said, adding that the Bureau of Reclamation has immediate powers to reduce Nevada’s share to 160,000 acre-feet if necessary. “We would fight like hell against that in court. … But we know we have to take more than we do today. We don’t know what the ceiling of that is, but we think 50,000 acre-feet is reasonable for what we’re seeing in the modeling.”

Permanent, temporary and future supplies

In its newest report, the agency has divided the region’s water supplies into permanent, temporary and future resources.

Permanent resources, such as the Colorado River and rights to pump groundwater in the Las Vegas Valley, are ones that water managers expect to be available for the foreseeable future. Temporary ones include excess water stored in groundwater banks in Arizona and California that could reduce strain on the system in one go.

“I don’t ever want to be in a situation where we’re building businesses, homes and schools based upon those temporary resources,” Pellegrino said. “But we may be in a situation where we’re under contract on a desalination plant, it’s under construction and we know that water’s coming online in five years, so we dip into these temporary supplies when we need to.”

Future resources are often the least reliable from a planning perspective. The agency expects to see more partnerships between states, as well as a share of water from delsalination projects.

It hasn’t ruled out about 13,000 acre-feet of groundwater pumping in other rural basins, though environmentalists put up a fight when the agency tried for years and failed to build a pipeline from White Pine County and do just that.

“In a climate change world where you have to adapt, all possible solutions have to be on the table,” said Pat Mulroy, who fought hard for the pipeline as the agency’s first general manager. “You can’t just carve certain ones out and say: ‘Well, those are sacred cows. We’re not going to touch it.’”

A ‘growth-agnostic’ agency

Someone who has heard more complaints about growth than anyone when it comes to water is Mulroy, who garnered a reputation for her no-nonsense approach to conserving water in the valley.

Mulroy said the point of creating the regional water authority in the ’90s was to take water out of the equation as it pertained to each respective city’s growth and conflicting water rights.

State funding is often divvied up based on how many people each city serves or is projected to serve, she said, and the agency takes water out of that equation.

“The SNWA was created to be growth agnostic, and it has to be,” Mulroy said. “There is competition in all areas of growth except water. We deliberately took water out, because otherwise we wouldn’t be sitting here today.”

And divorcing water from growth in Las Vegas is key to the economy, experts say. Pellegrino, of the water authority, said the agency is doing everything it can to avoid an official growth moratorium from becoming necessary.

Andrew Woods, director of UNLV’s Center for Business and Economic Research, said a growth moratorium in Las Vegas would penalize the region for the crisis along the river, when Southern Nevada’s water managers have been at the cutting edge of reducing consumption.

Industries like home-building, construction, retail trade and hospitality account for at least half of the state’s economy, Woods said, and slowing them down could have ripple effects, from a lack of available jobs to spikes in housing costs.

“Water doesn’t keep me up at night,” Woods said. “What I’m more worried about is economic diversification and the sustainability of the economy.”

The path ahead

Charting the most favorable path forward hinges on a few factors: the will of Mother Nature, reducing gallons of water used to 86 per person per day and the speed with which water managers develop new supplies. That compares with 235 gallons per person per day in 1990, 89 gallons per person per day in 2023 and 95 gallons per person per day in 2024.

The water authority’s projections take into account different predicted weather conditions, generally accounting for the worst case scenario if snow seasons fail to deliver.

Experts say the agency’s goal of 86 gallons of water per person per day is attainable, but would require more action from Southern Nevada residents, who are among the first in the American West to reconcile with initiatives like punitive excessive use fees.

“I do understand why people have pushed back against this and are upset. They’re being asked to do more and more over time,” said Elizabeth Koebele, who studies Colorado River policy at the University of Nevada, Reno. “But there is still more room to grow with outdoor water uses.”

Reining in outdoor landscape irrigation is the mission of ongoing efforts to create incentives for homeowners to convert their lawns to desert landscaping. The 2027 enforcement date for a state law that will make it illegal to water so-called “nonfunctional turf,” such as decorative grass in road medians, is coming up soon, too.

Mulroy hasn’t changed her stance that the Colorado River Basin as a whole needs to step up and seriously consider projects that would add water to the system, such as mass water recycling and ocean desalination.

Some of that could be coming — and Mulroy hopes it does quickly. The Water Infrastructure Finance Authority of Arizona, for instance, decided in November it would use state funds to pursue multiple proposals that could bring millions of acre-feet back to the system every year.

“You can’t wait until you’re sitting there with a gun to your head,” Mulroy said. “You don’t have time.”