Thursday, September 17, 2009

ROAD SALT AFFECTING URBAN STREAMS

Forbes - Many urban streams have become salty enough to harm aquatic life, largely because of salt used for deicing roads in the winter, according to a new government study. The U.S. Geological Survey studied urban streams and groundwater for levels of chloride, a component of salt, in 20 states spanning from Alaska to the Great Lakes and Northeast. It found chloride concentrations above federal recommendations designed to protect aquatic life in more than 40 percent of urban streams tested. The highest levels were measured in those streams during the winter - as much as 20 times the federal guidelines - when salt and other chemicals are commonly used for deicing.