Cape Town, South Africa, has been in the news lately as officials desperately try to keep it from becoming the first modern city to run out of water. Water supplies are being closely monitored to estimate “Day Zero,” the day they will turn off the municipal taps. It could happen as soon as July 15.

All of Cape Town’s 4 million residents are feeling the effects of a severe water shortage. Each person is asked to use just 13.2 gallons of water per day. (In comparison, the average American uses 80-100 gallons of water a day, according to the U.S. Geological Survey.) Should Day Zero become a reality, Cape Town residents will stand in line for a daily allotment of just 6.6 gallons each.

If the water restrictions seem drastic, it’s because Cape Town’s situation is. A record three-year drought already has depleted the city’s water supply to 25 percent of capacity. At 13.5 percent, Day Zero will be declared.

If a city such as Cape Town, with a sprawling coastline on the Atlantic Ocean, can run out of water, what are the chances it could happen in Arizona, the only U.S. state where parts of all four North American deserts can be found? Many Arizonans are well-versed on water conservation, but is it enough?

Could Tucson or Phoenix be the next Cape Town?

Sharon Megdal, director of the UA Water Resources Research Center, a Cooperative Extension and research unit in the College of Agriculture and Life Sciences, tackles the question by looking at the past, present and future of Arizona’s water situation.

Read more at the University of Arizona