The sand/salt mixture they use on the roads is very corrosive and of course the salt is highly toxic when it gets into the water, there are alternatives but they are more expensive in the short term, I.E when they buy the stuff but in the long term it does far less damage.
We have just had a week of bad weather luckily not too much snow where I live but anything more than an inch of snow seems to bring the entire country to a halt, and everyone always seems so shocked that we have cold weather in the winter.