America's Rivers Getting Saltier, Threatening Water Supplies

America's rivers streams are getting saltier due to road salt, sewage, mining and fertilizers used in agriculture. While few people will be happy about saltier tasting water and its uncertain effects on wildlife, a clearer concern right now is that America's aging water infrastructure was not built to handle saltier water. Just as road salts rust the metal of your car, dissolved salt in water reacts with the metal in water pipes.