Research: Road Salt Affects Mitigation Wetlands

Sacrificing one wetland for the sake of five others may be the way to go when planning constructed wetlands to replace those destroyed during road building, but a Penn State Erie biologist is monitoring the salinity of the wetlands to see how the salt affects animals and insects.

In November 2003, PennDOT completed a four-lane highway connecting Interstate 90 with the Erie waterfront. A portion of the road crossed the Penn State Erie campus. When building the section of road across the Behrend campus, PennDOT installed an elaborate drainage system beneath the road to collect all the runoff. The water goes to only one of the six constructed mitigation wetlands for the project and eventually runs downhill through woodlands. Researchers are measuring the amounts of salt that enter the designated runoff wetland and one other that is slightly affected by splashover from salt spreading and snow melting. They are also monitoring the insects and other animals living in the wetlands. So far, the research shows a large decrease in non-biting midges in the designated runoff wetland. The effect on other species is not yet known, but additional studies are being conducted.  http://www.eurekalert.org/pub_releases/2005-05/ps-rsa051905.php