Follow the Silt Why Stream Restoration Projects Fail By CORNELIA DEAN, NYTimes. 6/24/08 Science Times section, Page 1. Correction Appended, (Excerpt instructions below on how to get rest of article courtesy Herpdigest)
LITITZ, Pa. Dorothy J. Merritts, a geology professor at Franklin & Marshall College in Lancaster, Pa., was not looking to turn hydrology on its ear when she started scouting possible research sites for her students a few years ago. But when she examined photographs of the steep, silty banks of the West Branch of Little Conestoga Creek, something did not look right. The silt was laminated, deposited in layers. She asked a colleague, Robert C. Walter, an expert on sediment, for his opinion. Those are not stream sediments, he told her. Those are pond sediments. In short, the streamscape was not what she thought. That observation led the two scientists to collaborate on a research project on the regions waterways. As they reported this year in the journal Science, their work challenges much of the conventional wisdom about how streams in the region formed and evolved. The scientists say 18th- and 19th-century dams and millponds, built by the thousands, altered the water flow in the region in a way not previously understood. They say that is why efforts to restore degraded streams there often fail. Not everyone agrees, but their findings contribute to a growing debate over river and stream restoration, a big business with increasing popularity but patchy success. Many hydrologists and geologists say people embark on projects without fully understanding the waterways they want to restore and without paying enough attention to what happens after a project is finished. For the rest of the article go to http://www.nytimes.com/2008/06/24/science/24stream.html?ref=science or send a request to us for a text only version.
