According to a new study by the U.S Geological Survey, there has been a decline in the number of native fish and aquatic insects in urban and suburban streams at low levels of development. The species which are pollution sensitive are the most affected.
“When the area of driveways, parking lots, streets and other impervious cover reaches 10 percent of a watershed area, many types of pollution sensitive aquatic insects decline by as much as one third, compared to streams in undeveloped forested watersheds,” said Tom Cuffney, USGS biologist. “We learned that there is no ‘safezone,’ meaning that even minimal or early stages of development can negatively affect aquatic life in urban streams.”
To read more visit: http://water.usgs.gov/nawqa/urban/html/pubs/invert2010.html