CONCORD, N.H. (AP) — When roads turn into ice rinks, consider trying beet juice, molasses, and even beer or cheese waste to make them safer. So say experts who fear road salt is starting to take a toll on the nation’s waterways, putting everything from fish and frogs to microscopic zooplankton at risk.
Tossed onto sidewalks and dumped onto highways, salt for decades has provided the cheapest and most effective way to cut down on traffic accidents and pedestrian falls during winter storms. But researchers cite mounting evidence that those tons of sodium chloride crystals — more than 20 million nationwide each year — are increasing the salinity of hundreds of lakes, especially in the Northeast and Midwest.
“There has been a sense of alarm on the impacts of road salt on organisms and ecosystems,” said Victoria Kelly, a road salt expert at the Cary Institute of Ecosystem Studies in New York. “We’ve seen increasing concentrations in river water, lakes, streams. Then, scientists started asking the question: What is going to happen to the organisms living in freshwater bodies and what will happen to the freshwater bodies as a whole?”
Believed to be first used in the 1940s in New Hampshire, salt became the go-to de-icing agent as cities expanded, highways were built and motorists came to expect clear roads. More than a million truckloads a year are deployed in ice-prone climes, most heavily in the Northeast and Midwest.
But many state and local agencies are seeking ways to reduce salt use as its environmental impacts are becoming more apparent.
They have turned to high-tech equipment to spread salt more efficiently, better weather forecasting to time their salting, and liquefied organic additives that help salt stick to pavement. That reduces salt use by preventing it from washing away immediately.
Agencies from New Jersey to North Dakota are using a mixture that includes beet juice; New Hampshire and Maine use one with molasses. Highway departments also have turned to beer waste, pickle brine and, in at least one Wisconsin county, cheese brine.
“Adding salt to the environment does have negative impacts, but for those of us in the Northeast, especially in rural states, where driving is the predominant way of getting around, we need mobility,” said Jonathan Rubin, director of the Margaret Chase Smith Policy Center and lead author on a 2010 report on the cost and benefits of salting Maine roads.
“In my opinion, we are always going to be using some degree of road salt,” he said. “The question is, can we use less?”
Salt corrosion already causes billions of dollars in damage each year to cars, roads and bridges — and now there are growing signs it’s making freshwater ecosystems saltier. In the past 50 years, chloride concentrations in some lakes and rivers quadrupled and, in a few, increased a hundredfold.