Treehugger, via AlterNet:
Southeast US in as Much Water Trouble as Desert SouthwestIt's usually the southwestern US that makes the news for its water woes, what with its deserts climates and high populations. However, researchers state that the southeast is in just as much trouble when it comes to having adequate water supplies for future years. From issues to storing enough water, to reduced rainfall and more frequent droughts, the southeastern states are likely to feel the water crunch in the very near future.
Western Farm Press reports on a new paper published in the Proceedings of the National Academy of Sciences that focuses on the water problems of the southwest, but points out that the southeast has similar problems.
While the southeast has a multitude of reservoirs, they rely on annual rainfall to replenish. Because rainfall is more sparse during rainy seasons and droughts are more frequent, those reservoirs are less and less reliable. Additionally, the reservoirs lose storage capacity as they fill with sediment. Smaller reservoirs lose more water to evaporation than large ones, which means over all, the reservoirs just don't hack it.
From Western Farm Press:
In order for water supply to be considered sustainable, the researchers calculated that no more than 40 percent of freshwater resources can be appropriated for human use, to ensure that streamflow variability, navigation, recreation and ecosystem use are accommodated. They also determined how much water a region would need to meet all its municipal, agricultural and industrial needs--its virtual water footprint. The VWF includes the water needed if a region were to grow enough food to support its own population.
The researchers found that neither the Southwest nor the Southeast have enough water capacity to meet all their own needs; both these regions virtually import water from other parts of the country, in the form of food. "The Southeast has virtually no positive, inland VWFs," said Kominoski, who earned his doctoral degree from the Odum School. "The largest population centers in southeastern states, with the exception of Florida, are inland. Piedmont cities such as Atlanta, Charlotte and Birmingham rely on small watersheds, which may be why our VWFs are negative."
The researchers also note that their estimates -- based on information from 1950-99 -- is on the conservative side, since this past decade has been one of the hottest on record, and more frequent droughts are expected in coming years. ...........(more)
The complete piece is at:
http://www.alternet.org/newsandviews/article/399302/southeast_us_in_as_much_water_trouble_as_desert_southwest/