Nick Fetty | January 13, 2015
A University of Iowa civil and environmental engineering professor is working with the Departments of Transportation in several states to make sure efficient salt application is being practiced on icy and snowy roads this winter.
Wilfrid Nixon – who also holds appointments with the Center for Global and Regional Environmental Research as well as IIHR Hydroscience & Engineering – aims to lessen the amount of salt used by road crews which would save money and also cause less damage to the environment.
One specific technique Nixon emphasizes is the timing of salt application. When pavement temperatures are extremely cold – such as last week – the salt can be ineffective in melting snow and ice. To better inform the public about current road conditions, the Iowa Department of Transportation has launched an online map which shows snowplow locations and video to give users a better sense of road conditions.
Nixon points out that salt is generally more effective than dirt and sand which can be applied to roads to create more traction but dirt and sand are often blown off the road because of traffic. Excessive salt application will eventually runoff the road too and can cause issues on the land and in the water by the time spring comes around. Researchers at Washington State University have been studying the effects of over-salting on roadways.
During an average year, the Iowa Department of Transportation applies approximately 12 million gallons of brine and 200,000 tons of rock salt to Iowa roadways.