Water Supplies Imperiled

ASEE Prism, Feb 2008 by Grose, Thomas

CLIMATE

Nearly 40 percent of the world's population lives less than 100 miles from a shoreline, areas generally defined as coastal. And because of global warming, they may be at risk of losing up to 50 percent more of their freshwater supplies than previously predicted, according to a new Ohio State University study based on simulations.

OSU geologists used data from the Intergovernmental Panel on Climate Change that indicate sea levels could rise as much as 23 inches over the next 100 years. As the rising sea water covers more land, it will also contaminate underground freshwater aquifers, creating undrinkable brackish water. It had been assumed that as the seas came inland, the salt water would penetrate below ground only as far as it moved inland above ground. But the OSU simulations found that, depending on the types of sand involved, brackish water can penetrate aquifers up to 50 percent further inland than the seawater itself reaches. Some of the most vulnerable areas-the U.S. East Coast and the Gulf of Mexico-are also some of the most populated.-TG