Effects Of Road Deicing On Environment

The expansion of the roadway network and an increase in traffic volume has resulted in significant degradation of the surrounding environment bordering roads by altering habitat, isolating plants and animal populations, spreading pollutants and exotic species into the surrounding landscape, and increasing human access to environmentally sensitive areas.

In northern regions of the globe, roads can also be a major source of contamination of surrounding soils and water bodies as a consequence of spreading road salt, sand, and other materials for winter road maintenance.

“Deicing roads is necessary to maintain safe travel conditions for motorists and travelers in cold regions during the winter months,” said Clarkson University Professor of Biology Tom Langen. “But road salt (sodium chloride) is readily transported through soil and into water bodies. Although non-toxic in low concentrations, at high concentrations it stresses plants and animals, ultimately eliminating native salt-intolerant species and promoting the growth of salt tolerant ones, including non-native invasive species.”

Langen and fellow researchers associated with Clarkson University’s Center for the Environment and Paul Smith’s College of the Adirondacks have formed a multidisciplinary team to assess the long-term environmental consequences of current winter road maintenance practices on soils and lakes in the Adirondack Park of New York State, and to identify alternatives that may be less environmentally harmful.

Their research is focused on three lakes along New York State Highway 73, a heavily traveled mountain roadway and the main route to Lake Placid, a year-round tourist destination. The project is largely funded by the New York State Department of Transportation; the New York State Department of Environmental Conservation and the Adirondack Park Agency are also sponsors.

The two lakes that are the primary focus of the study, Upper Cascade Lake and Lower Cascade Lake, are popular destinations for outdoor recreationists. These lakes also maintain the state’s largest populations of round whitefish, a species that is classified as endangered in New York. In sampling the Cascade Lakes recently, the scientists have found concentrations of chloride that are over 100 times higher than expected in typical Adirondack lakes, and the concentrations appear to be increasing.

“There has long been concern about environmental implications of heavy road salt and sand applications along Highway 73 in the Cascade Lakes watershed,” explained Langen. “Environmental advocacy groups have pressured state agencies to alter road management activities. However, winter weather is exceptionally severe along this stretch of highway, and local residents and other road users are justifiably concerned that any changes in winter road management not reduce road safety.”

Cascade Lakes project team members Langen and his colleague, Clarkson Professor of Biology Michael Twiss, are working with graduate students from Clarkson’s Environmental Science and Engineering Program to measure water quality of the lakes each month over a period of two years and to assess the impact of elevated chloride levels on aquatic organisms. They are also examining changes in soil structure and chemistry alongside the roads that may result in stress or death to roadside trees. Curt Staiger, a scientist from Paul Smith’s College, is reconstructing changes in the lakes’ water quality over the last two centuries using sediment cores, and comparing these changes to the timing of human activities along the lakes, including road construction and changes in winter road maintenance practices.

Faculty members of Clarkson’s Department of Civil and Environmental Engineering are also part of the team. Associate Dean of Engineering Thomas Young and a graduate student are creating a model of the fate and transport of chloride in the watershed. From this model, the scientists should be able to predict the long-term environmental impacts from present winter road management practices, and whether those impacts might be reduced by alternative management strategies. Professor of Civil and Environmental Engineering Kerop Janoyan is reviewing alternative methods of constructing roads to reduce the need for chemical deicers and abrasives as well as the feasibility of applying alternative chemical deicers to road salt.

The researchers will provide recommendations on what practices might be most environmentally benign along Highway 73 and similar roadways.

“Our road salt study has led to a collaboration among researchers from two universities – whose expertise include limnology, ecology, and civil and environmental engineering – and policymakers from three state agencies,” said Langen. “It also is proving to be an excellent project for training students in environmental science and engineering. Most importantly, the project should yield some definitive results and recommendations that will help keep the roads safe for motorists and protect the waterways and forests in the surrounding environment.”

Clarkson University, located in Potsdam, New York, is an independent university with a reputation for developing innovative leaders in technology-based fields. Its academically rigorous, collaborative culture involves 2,700 undergraduates and 350 graduate students in hands-on team projects, multidisciplinary research, and real-world challenges. Many faculty members achieve international recognition for their scholarship and research, and teaching is a priority at every level. For more information, visit http://www.clarkson.edu.