False Alarm (No 2155): U.S. Water Supply Not As Threatened As Believed, Study Finds
Although reports of drought conditions, water wars and restrictions have often painted a bleak picture of the nation’s water availability, a new University of Florida survey finds that conditions aren’t quite so bad as believed.
Jim Jawitz, a UF soil and water science professor, and Julie Padowski, who earned her doctoral degree from UF and is now a postdoctoral researcher at Stanford University, knew that previous assessments of urban water supplies typically used what is known as a “runoff-based approach,” which takes into account factors such as river flows and rainfall amounts.
Jawitz and Padowski knew that those assessments did not consider the infrastructure used to maintain urban water supplies, such as water stored in aquifers, lakes, reservoirs or water that’s pumped in to an area and stored. So for 225 U.S. metropolitan areas with populations of more than 100,000, that’s what they did, and their findings have been published online by the journal Water Resources Research.
When assessing cities using the runoff-based approach, the UF study found that 47 percent of the total U.S. population is vulnerable to water scarcity issues, however, when infrastructure was accounted for, the number dropped to just 17 percent of the population. Residents in the top 225 metropolitan areas make up the bulk of the U.S. population.
Jawitz, a faculty member with UF’s Institute of Food and Agricultural Sciences, said they expected to find fewer areas vulnerable to water shortages than past studies had because of the different methodology, but some of their findings surprised them.
“We have people who live in the desert and they have water and it’s because of their infrastructure. If you live in a city that has a large of reservoir of water stored and there’s a drought, it doesn’t have the same effect on you as if you live in a city where there’s a drought and you don’t have a large reservoir,” he said.