Several Western states, including Arizona, California, New Mexico, Utah, Nevada and parts of Oregon and Colorado, are in the grips of a historic drought that has depleted key water sources to a frightening level as temperatures rise and wildfire risk increases. Many scientists are ringing alarm bells that it could mark a tipping point in the water crisis that threatens life in the West as we know it, particularly agriculture.
“The word drought just doesn’t do it anymore,” said John Fleck, a professor in water policy at the University of New Mexico. “Drought implies a dry spell that ends with a wet spell. And climate change is fundamentally changing things… The landscape is drying out, the headwaters are drying out. It’s just a different world now with less water and warmer temperatures.”
The conditions seen across much of the West this summer are part of what some scientists have called a “megadrought” that started in the year 2000, with some years drier than others. Other experts say it’s one of a number of more severe droughts punctuating a two-decade-long dry spell. Whatever you call it, it’s bad.
“It’s one of the longest droughts that we’ve had in 100 years. The longest and the most severe,” said Brian Richter, chief scientist for the Global Water Program of The Nature Conservancy. “It would have been bad even without climate change, but climate warming is accentuating it, it’s making it worse.”
How drought happens
Three main factors contribute to the natural phenomenon of drought: snowpack, soil moisture and temperatures.
The Western states depend on snowpack for a good portion of their water supply. Essentially, snow falls on the peaks of mountains in the winter, and spring temperatures melt the snow, which travels down the mountain into reservoirs like Lake Mead and Lake Powell.
But soil gets the first drink of water from the snowmelt as it makes its journey. The drier the soil, the more it drinks and less water will be captured in the reservoirs. And right now, the soil across the region is exceptionally dry. In Arizona, for example, 2020 was a typical year for snowpack, but the soil was so dry that not enough water entered the reservoirs, said Ted Cooke, general manager of the Central Arizona Project.
Then there’s the heat. The region is smashing temperature records, with Northern California and the Pacific Northwest experiencing Southwestern-like triple-digit weather for the first time.
With higher temperatures, there is less snow and the snowpack melts earlier. Water also evaporates quicker when temperatures are high, which contributes to drier soil and receding water levels in reservoirs.
Lake Mead and Lake Powell, which provide water to over 25 million people in Arizona, California, Nevada and parts of Mexico, are at their lowest water levels in history: 36 and 34 percent capacity, respectively.
Saving water for the future
Governments and water managers are in a crisis mode trying to figure out how to conserve water while ensuring people still have access to it in the long-term. While most people will not feel the effects of any water cuts, farmers are among the first to feel the brunt of shortages. Agriculture uses about 80% of the water from the Colorado River which feeds Arizona, California, Nevada and parts of Mexico. In Arizona, some farmers will have their water allotments reduced in 2022, said Cooke. He added that the shortage will likely require further water reductions as soon as 2023.
Looking at a future of drier and drier conditions, some farmers are adapting to more water-efficient technologies and crops, but not all are able to make these changes because of financial or logistical constraints, said Felicia Marcus, former chairwoman of the California Water Resources Control Board. She said incentives for farmers to switch to more water-efficient strategies could help conserve water in the long-run. For those who can’t farm efficiently enough to justify their water needs, incentives could help them retire or change careers.
While the situation is dire, water isn’t going to run out any time soon. But think of the water supply as a bank account. The West has been overdrawing the account for years, and now it’s time to catch up with overdraft fees.
Many cities get water from local reservoirs and manmade lakes that fill up faster and serve smaller populations. Cities and governments have efficient ways to store water underground that could sustain populations for 100 years or more.
How people use water will have to change to ensure adequate supplies further into the future. People in the West have to adapt to the reality of living drier, said Sarah Porter, director of the Kyl Center for Water Policy. This could mean letting lawns turn brown in the summer, using more efficient appliances and for corporations to better reuse water and wastewater.
Conserving water will not solve the water shortage, but it helps give municipal water managers more flexibility as they work to figure out solutions, said Tom Buschatzke, director of the Arizona Department for Water Resources. It also can help postpone curtailment, which would cut off and reduce water supplies.
Droughts are natural events in the West, and this particular one will not be the last. Preparing for these periods of dryness is essential in order to continue living in these regions — and in the meantime, hoping for rain won’t hurt.
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What’s causing the drought in the West — and why it’s so bad - PBS NewsHour
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