- Because the freezing point of salty water is a lower temperature than pure water, scattering some salt atop ice or snow can help accelerate the melting process, opening up the roads to traffic that much sooner. It's estimated that more than 22 million tons of salt are scattered on the roads of the U.S. annually—about 137 pounds of salt for every American.
They dump pea gravel on the roads in Portland as an alternative to salt. After the melt the roads are gravel coated in some areas for weeks. The gravel gets kicked up, chipping windshields occasionally hitting pedestrians. It's super dangerous for motor and bicyclists. I hate it, every corner is a death trap riding your bike in traffic.
I think it was mike that told me that in Norway, they do the same thing - the gravel - but in the spring, they send street sweepers out and gather a huge percentage of it back up. They actually recycle gravel... The Denver Metro area often dumpers gravel too. It's pretty frustrating. I'm convinced that the gravel industry is sponsored by Safelite Autoglass. My windshields look like crap after ONE winter.
They use a corn based product here, because Midwest. The corn is cut into the salt to make it more friendly to cars and vehicles because salt is vile stuff when it gets in bare metal. They also use beets in some parts of the south, and in Wisconsin, they use a cheese byproduct. When I moved out here I was expecting to find dead plants on the sides of the roads, almost like a dead zone where the salt washed off the sides of the road. Instead there is a thicker growth of thistle on many of the state roads that they salt. And deer. Holy shit the deer that are on the sides of the roads in winter to get at the salt.
Someone that spent their whole life in a desert clime...or the Caribbean...or the South Pacific...is now very surprised to find this out.