Arizona

Arizona is one of the fastest-growing states in the U.S., with an economy that offers many opportunities for workers and businesses. But it faces a daunting challenge: a water crisis that could seriously constrain its economic growth and vitality. A recent report that projected a roughly 4% shortfall in groundwater supplies in the Phoenix area over the next 100 years prompted the state to curtail new approval of groundwater-dependent residential development in some of the region’s fast-growing suburbs. Moreover, negotiations continue over dwindling supplies from the Colorado River, which historically supplied more than a third of the state’s water. The Colorado River’s watershed extends across seven U.S. states and into Mexico. Use of river water is governed by a compact negotiated in 1922. Center for Colorado River Studies, CC BY-ND As a partial solution, the Arizona Water Infras...

Scorching temperatures have put millions of Americans in danger during recent heat waves, with heat extremes hitting states from coast to coast. Phoenix hit 110 degrees Fahrenheit (43.3 Celsius) or higher every day for over three weeks in July 2023. Other major cities, from Las Vegas to Miami, experienced relentless high temperatures, which residents described as “hell on earth.” While the evening news runs footage of miserable sunbathers and joggers dousing themselves with water, these images conceal a growing hidden crisis: the millions of older adults who are suffering behind closed doors. As researchers who study older adults’ health and climate change, we have found that two societal trends point to a potentially dire future: The population is getting older, and temperatures are rising. During the July 2023 heat wave, people gathered at the Justa Center, a day cooling center in downtown Phoenix for people age 55...

The Navajo Nation, the largest Native American reservation in the U.S., covers 27,000 square miles (70,000 square kilometers) in the Southwest – an area larger than 10 states. Today it is home to more than 250,000 people – roughly comparable to the population of St. Petersburg, Florida, or Winston-Salem, North Carolina. Unlike those cities, however, 30% of households on the Navajo Reservation lack running water. Hauling water can cost 20 times what it does in neighboring off-reservation communities. While the average American uses between 80 and 100 gallons (300-375 liters) of water per day, Navajo Nation members use approximately seven. Since the 1950s, the Navajo Nation has pressed the U.S. government to define the water rights reserved for them under the 1868 treaty that created their reservation. These efforts culminated in a U.S. Supreme Court case, Arizona v. Navajo Nation, which posed this question: Does the treaty between the Navajo Nation and the United S...

Arizona, California and Nevada have narrowly averted a regional water crisis by agreeing to reduce their use of Colorado River water over the next three years. This deal represents a temporary solution to a long-term crisis. Nonetheless, as a close observer of western water policy, I see it as an important win for the region. Seven western states – Colorado, Wyoming, Utah, New Mexico, Arizona, Nevada and California – and Mexico rely on water from the Colorado River for irrigation for 5.5 million acres and drinking water for 40 million people. Their shares are apportioned under a compact negotiated in 1922. We now know, thanks to tree-ring science, that its framers wildly overestimated how much water the river contained on a reliable basis. And climate change is making things worse. Some recent commentators have argued for revamping the compact. The lawyer in me shudders to think of the utter chaos that would ensue as states, tribes that were left out of the original...

After three years of extreme drought, the Western U.S. is finally getting a break. Mountain ranges are covered in deep snow, and water reservoirs in many areas are filling up following a series of atmospheric rivers that brought record rain and snowfall to large parts of the region. Many people are looking at the snow and water levels and asking: Is the drought finally over? There is a lot of nuance to the answer. Where you are in the West and how you define “drought” make a difference. As a drought and water researcher at the Desert Research Institute’s Western Regional Climate Center, here’s what I’m seeing. How fast each region recovers will vary The winter of 2023 has made a big dent in improving the drought and potentially eliminating the water shortage problems of the last few summers. I say “potentially” because in many areas, a lot of the impacts of drought tend to show up in summer, once the winter rain and snow stop and the...