5 things to know about drought in the American West
A new climate is re-writing the story of U.S. drylands
Harsh and unrelenting. But also transformative?
The dry conditions blanketing much of the American West are setting records nearly every week. Lakes Mead and Powell, the country’s largest reservoirs by capacity, dropped to new lows this year. The Great Salt Lake did, too. This spring, New Mexico endured its largest ever wildfire. Even with those distinctions, more are likely on the way. The hottest months of the year are still to come.
Shortened time frames are now the norm. Water cuts that were once nearly unthinkable even in the long term in the Colorado River basin are now being implemented in a matter of months, not years or decades. Still, some see opportunity in calamity, a chance to reposition the region for trials to come.
“While the situation is objectively bleak, it is not in my view unsolvable,” John Entsminger, the general manager of the Southern Nevada Water Authority, told a Senate panel on June 14. Basin officials are steeling themselves for short, intense negotiations.
It amounts to a season of potentially long-lasting change for some of the country’s fastest-growing states and biggest economies.
Here are five things to know about how the drought is re-writing the story of America’s drylands.
1. It’s a hot drought
The drought is not just a failure of precipitation. Rising temperatures due to global warming are also depleting the region’s rivers.
The mechanisms are easy to understand. Extreme heat bakes the land surface. Warmer, drier air holds more water. Parched soils then gobble rain and melting snow before the water reaches rivers and reservoirs. A thirsty atmosphere evaporates or sublimates its share. Together, they are a powerful one-two punch.
With increasing temperatures, “we’re seeing places that do have drought, the intensification is more rapid,” says Roger Pulwarty, a senior scientist in the physical sciences laboratory at the National Oceanic and Atmospheric Administration.
The Colorado River basin illustrates the impacts of a hot drought. According to the Colorado Basin River Forecast Center, precipitation in the watershed above Lake Powell since October was 94 percent of the 30-year average. In other words, just a tick below normal. Snowpack peaked at 83 percent of average. Yet only a fraction of that water made it into Lake Powell. Runoff into the lake this summer is just 56 percent of average. A hot drought is a stealthy thief.
2. Drought has a long reach
When water stops flowing, difficult days are ahead.
Forests become tinder boxes, a spark removed from calamity. Already there have been massive disruptions. U.S. Forest Service staff lost control of a prescribed burn in Santa Fe National Forest in April, resulting in the 341,000-acre Hermits Peak-Calf Canyon fire, the largest wildfire on record in New Mexico.
“Drought, extreme weather, wind conditions and unpredictable weather changes are challenging our ability to use prescribed fire as a tool to combat destructive fires,” wrote Randy Moore, the chief of the U.S. Forest Service, in an incident assessment.
Hydropower is weakened. With less water in reservoirs, generators crank out fewer megawatt-hours, raising the cost of electricity and increasing the risk of summer blackouts. In California last year, hydropower generation was nearly half the 10-year average. This year, Glen Canyon Dam is operating at just 60 percent of its maximum electrical generating capacity due to the drying of Lake Powell.
There are human health consequences when lakes are depleted. Earlier this month, the Great Salt Lake dropped to its lowest point since record-keeping began in 1847. Receding shores expose more lakebed salts and dust, which become a respiratory hazard during windstorms — and can hasten snowmelt in the mountains.
Ecosystems — and the birds and fish that depend on them — are also under stress. Utah regulators have identified high numbers of toxin-producing algae in the southern reaches of Utah Lake, a water body notorious for summer algae outbreaks. In California, sampling carried out in June by the Environmental Protection Department of the Big Valley Band of Pomo Indians revealed algal toxins in Clear Lake that were higher than state advisory levels. These hazardous outbreaks typically worsen deeper in the summer.
3. Cutbacks are inevitable
When supply ebbs and reservoirs are near record lows, authorities have one durable tactic: reduce demand.
In fits and starts, that is happening. California regulators passed an emergency order in June that took small steps to address the supply-demand imbalance. The order prohibits businesses, industries, schools, churches, and other institutions from watering “non-functional” grass with potable water. What’s non-functional? Grass that covers median strips and office parks.
Cities and farms that are customers of the two major canals in California — one state and one federal — already had their allocations substantially reduced as a result of below-average reservoirs. With less water, irrigators will fallow more land.
The largest cuts, however, will be in the Colorado River basin. Camille Touton, the commissioner of the Bureau of Reclamation, said in June that the states would have to reduce their draw on the river by two million to four million acre-feet in the next year.
Entsminger of the Southern Nevada Water Authority called the proposed cuts “a degree of demand management previously considered unattainable.”
Their plan is due next month.
4. Drought is political
The right to use water in the western states is subject to arcane laws, court decrees, and precedents, some of which date to the era of colonial settlement.
Persistently dry conditions and a reckoning with historical inequities are forcing residents and lawmakers to reassess the established way of doing business.
In June, the Nevada Supreme Court upheld a groundwater management plan for Diamond Valley irrigators that abandons long-held principles of state water law, such as the priority system that privileges senior water rights and “use it or lose it” requirements.
Activists in Arizona are gathering signatures to put groundwater regulation on the ballot. Their citizen’s initiative would ask voters to approve two Active Management Areas in Cochise and Graham counties, places where big farming operations have dried up shallow wells and caused the ground to fracture, damaging highways.
“Dams Not Trains” billboards dot the highways of California’s Central Valley, a plea by the region’s biggest farmers for legislators to redirect their spending preferences. At the same time, a budget proposal in the California Legislature would direct $1.5 billion to buy senior water rights from farmers in order to keep more water in rivers.
A relatively recent development is the political muscle of the region’s Indian tribes. Acting as dealmakers, tribes have emerged as key players in water supply negotiations, particularly in Arizona, where the Gila River Indian Community has leased water to cities and pledged to conserve 129,000 acre-feet this year to boost water levels in Lake Mead.
5. Drought is probably the wrong word
To some researchers and advocates, we shouldn’t even be calling this a drought.
Drought, they say, implies a temporary condition, a deviation from normal.
But what is happening in the Colorado River basin and other western regions is a shift toward a drier climate.
Even though precipitation in this two-decade period is anomalously and historically low, climate modeling suggests that the region is not going to snap back to the wetter periods of a generation ago.
To describe this new era, they prefer a different term: aridification. Clunky, perhaps. But more accurate.
A collective of respected Colorado River scholars argued in a 2018 paper that language change was necessary and could possibly induce behavioral change on the scale required to meet the challenge.
“A very modest starting point,” they wrote, “is to admit words such as drought and normal no longer serve us well, as we are no longer in a waiting game; we are now in a period that demands continued, decisive action on many fronts.”
This story is part of Covering Climate Now, a global journalism collaboration strengthening coverage of the climate story.