Read the full story in Time.
Ice-free roads may be good for drivers, but scientists warn that salt is seeping into lakes and rivers, including the Mississippi, killing wildlife and posing health risks to humans. Salt also corrodes asphalt and metal, causing some $5 billion in damage each year to roads and cars. And it lures deer and moose onto highways to lick it up, triggering accidents.
And yet, North Americans are addicted to road salt. Road crews have been pouring the stuff in ever greater quantities since the 1950’s, when cars and highways began to proliferate across the region. According to the U.S. Geological Survey, the amount of salt used on U.S. roads ballooned from 1 million tons in 1954, to 10 million tons in 1985, to around 24 million tons a year by 2019, as drivers demanded increasing levels of safety and convenience. “Fifteen years ago, it wasn’t common practice to expect dry pavement after snow,” Gleason says. “But somehow this idea has taken over that everyone should be driving like it’s summer in the winter.”