The road salt sprayed from the rear ends of trucks in winter—a staple of the season in the Northern US and Southern Canada—melts ice and keeps cars from careening off the road, but it also makes our freshwater lakes salty and possibly unsuitable for the things we need them for most: drinking water, irrigation, habitat for fisheries and more.

In a recent study examining the scale of freshwater lake salinization in North America, Scientists from the University of Wisconsin found that lakes near any kind of impervious surface— "as little as one road," limnologist and lead author Hilary Dugan told Motherboard over the phone—are at high risk of becoming too salinized within the next 50 years for either freshwater life or human use. This includes 27 percent of all large lakes in the US.

The study is published in Proceedings of the National Academy of Sciences.