Madison WI still uses salt, but we also use a lot of a mixture of sand and salt, which looks like pure sand from a distance, and liquid salt solution sprayed directly on dry roads before snowstorms when possible. The city claims that both of these methods, while not eliminating salt, greatly reduce its use.
The city also puts out piles of sand-salt for residents to use, so I usually grab some at the start of the winter. The mixture is easier to store than either sand or salt by themselves. For instance, a pile of salted sand won't freeze solid.
Salt works by freezing point depression. You can throw salt on sheet ice and it will melt the ice, until it gets too cold. Calcium chloride works to even lower temperatures.
Does putting all this salt on the sidewalks and driveways of your house affect plants around your house? I would imagine that over the years the salt buildup in the soils around everyone’s house would be immense. In ancient times they would salt enemies agricultural land to prevent plants from growing. Do plants not grow near to sidewalks and driveways in the Midwest?
Plants grow anywhere in the Midwest, just not the ones you want. ;-)
Yes to some extent. We actually use the sand/salt quite sparingly, because shoveling usually takes care of things. Just a bit on the front steps, and in a couple places where it tends to ice up on the sidewalks in late winter.
Probably the main source of salt is what gets thrown from the street by the plow trucks.
The lot slopes down towards the street, which helps, and what happens to the grass on the boulevard, we basically don't care. The weeds seem happy enough. The University of Wisconsin has actually developed varieties of trees that are resistant to salt, and we have those varieties out front.
At my workplace they salt more heavily, and have had to re-sod the grass near the walkways. But I think that's the result of several factors, including over-fertilizing during the summer, and maybe having a variety of grass that's less salt tolerant than our weeds. We also don't fertilize or water our lawn.
Up here in the Fox Valley we've been using brine and selectively salting roads to reduce salt usage. There are concerns about sand usage adding sediment to storm drains and into Winnebago, but I think the same applies to salt as well.
The city also puts out piles of sand-salt for residents to use, so I usually grab some at the start of the winter. The mixture is easier to store than either sand or salt by themselves. For instance, a pile of salted sand won't freeze solid.
Salt works by freezing point depression. You can throw salt on sheet ice and it will melt the ice, until it gets too cold. Calcium chloride works to even lower temperatures.