More than 50 percent of Pennsylvania's streams are polluted as a result of decades of coal mining operations. Drinking water in 39 of the state's 69 counties is affected.
In many municipalities in the United States, the infrastructure that conveys and sanitizes water is deemed inadequate. Miles of underground pipes have been corroding due to age, allowing lead into drinking water. Water treatment plants that were built at the turn of the 20th century to filter out particles and destroy bacteria regularly fail to remove pesticides, chemicals and other harmful materials.
Mercury, copper, chromium, arsenic, gasoline and ammonia-based perchlorate are showing up in increasing concentrations in the nation's water supply. Furthermore, surging population growth in states such as California, Texas and Florida have created severe water shortages.
Agriculture, too, is straining U.S. surface water and groundwater supplies. The groundwater that provides 31 percent of the water used to irrigate crops is depleted 160 percent faster than its recharge rate.
Experts agree that current technology provides limited solutions to the nation's water problem.
Desalination has proven effective in some areas, but the process of removing salt from seawater uses large amounts of energy. Pulsed-laser technology and bioremediation destroy only microbes, not metals and other toxic materials.
One promising technology is gray-water filtration, which sends ultra-clean drinking water to household faucets while diverting partially filtered water to washing machines, boilers and backyard pools. However, the process requires costly adaptations to residential plumbing.
According to the American Society of Mechanical Engineers (ASME), the solution to America's water problem lies in government and community activism.
