The United States is facing a serious water supply problem, researchers from the Cooperative Institute for Research in Environmental Sciences (CIRES) at the University of Colorado Boulder have warned.
A new study conducted by the team of scientists has found that in about 10 percent of U.S. watersheds the demand for water exceeds natural supply, putting them in the category of "stressed" watersheds. Researchers predict that because of climate change low water flow seasons will become more common over the coming years, causing more stress to watersheds.
Leader of the study Kristen Averyt, associate director for science at CIRES, commented that by 2050 several regions across the United States will have less reliable surface water supplies, which will cause serious problems for agriculture and municipalities.
For their study, the researchers analyzed a large set of data related to supplies and demand for freshwater in 2,103 watersheds across the United States. They isolated instances of severe water stress between 1999 and 2007 and projected future water stress for each watershed based on a climate change database.
Researchers identified the U.S. West as particularly vulnerable to water stress for two main reasons: There is very little gap between supply and demand in the region, so any change in balance could cause stress, and water supplies in the west have been secured by the use of imported or stored water to be able to meet the demand.