The biggest rivers in the U.S. are the lifeblood of the regions they flow through. They provide drinking water, irrigation for agricultural lands and a habitat where important ecosystems can thrive.
But as climate change worsens, some of the nation’s most important rivers are in serious trouble because of the drought gripping several regions.
For decades, Western cities like Las Vegas and Tucson, Ariz., have embraced water conservation and recycling as a means of preparing for a multidecade drought like the one we’re experiencing. Despite our best efforts, our neighbors in Southern California, Northern Arizona and Utah have not always followed our lead. Cities like Phoenix, Los Angeles and St. George, Utah, have been allowed to grow at an explosive pace with little planning for where water would come from or how long the supply would last.
It’s a picture-perfect day in Southern California. The sun is beating down on this Carlsbad beach, where volleyballs hit the sand and surfers paddle out into the waves. Just steps from here, the salty water lapping the shore is being transformed.
This beach neighbors the largest desalination facility in the Western Hemisphere. The Carlsbad Desalination Plant uses a complex web of pipes, tanks and specialized filters to pull salt and impurities out of ocean water, turning it into part of the drinking supply for San Diego County.
Water managers are feeling the crunch of a supply-demand imbalance along the Colorado River. Fresh water reserves are shrinking as climate change squeezes the river that supplies 40 million people and fields of crops across seven states. Some have proposed desalination technology as a way to augment that supply, easing the strain on a river that supplies a growing population from Wyoming to Mexico. Experts say it could be part of the solution, but likely won’t make much of a dent in the region’s water crisis.
At the Carlsbad plant, former seawater poured into a cup from a freshwater spigot. Michelle Peters, technical and compliance manager for plant operator Poseidon Water, held it and took a drink.
“At 10 a.m, the morning surfers were swimming in it off the coast in the ocean here,” she said. “Now it’s high-quality drinking water, ready for consumption.”
For over 30 years, I’ve been a climate scientist who has focused intensely on the causes and consequences of drought and climate change. I’ve done my research all over the planet, but my No. 1 focus has been on interactions of drought and climate change in the Southwest United States and on how drought and climate change are impacting the Colorado River. Seven states in the U.S. and Mexico depend on the Colorado River for water, yet I worry most about one state: Arizona.
Global scientists reported in August that due to the climate crisis, droughts that may have occurred only once every decade or so now happen 70% more frequently. The increase is particularly apparent in the Western US, which is currently in the the throes of a historic, multiyear drought that has exacerbated wildfire behavior, drained reservoirs and triggered water shortages.
More than 94% of the West is in drought this week — a proportion that has hovered at or above 90% since June — with six states entirely in drought conditions, according to the US Drought Monitor. On the Colorado River, Lake Mead and Lake Powell — two of the country’s largest reservoirs — are draining at alarming rates, threatening the West’s water supply and hydropower generation in coming years.
The water level of Lake Mead, the country’s largest reservoir, has dropped more than 130 feet since the beginning of 2000, when the lake’s surface lapped at the spillway gates on Hoover Dam.
Twenty-one years later, with the Colorado River consistently yielding less water as the climate has grown warmer and drier, the reservoir near Las Vegas sits at just 39% of capacity. And it’s approaching the threshold of a shortage for the first time since it was filled in the 1930s.
A new survey shows arsenic levels in public water are disproportionately high in certain U.S. communities, despite national regulatory standards designed to protect people from the harmful chemical. Researchers studied approximately 13 million records from 2006 to 2011 covering 139,000 public water systems in 46 states, Washington D.C., and Native American tribes.
Here at 12,000 feet on the Continental Divide, only vestiges of the winter snowpack remain, scattered white patches that have yet to melt and feed the upper Colorado River, 50 miles away.
That’s normal for mid-June in the Rockies. What’s unusual this year is the speed at which the snow went. And with it went hopes for a drought-free year in the Southwest.
A growing body of research shows that the Upper Colorado River Basin is growing warmer on average. In fact, the national hot spot centers on Western Colorado and much of the Southwest.
Defying environmentalists and public health advocates, the Trump administration on Thursday will announce the replacement of Obama-era water protections with a significantly weaker set of regulations that lifts limits on how much pollution can be dumped into small streams and wetlands.
The changes to the Clean Water Act’s protections are expected to hit California and other Western states especially hard.
The Water News Network is San Diego County’s source for water news and information.
