Actually there is a whole lot more to the salt on roads story in Canada. Envioronment Canada - federal regulator- has deemed road salt to be a toxic substance.
Road authorities are mandated by EC to develop salt management plans, and as other posters suggest - it is mostly an Eastern Canada thing to use road salt - on the western praries the winters are too cold for it to be effective. Some of the alternatives are more expensive magnesium 'salts'. The most innovation to come from the road salt reduction though, has been in the areas of brine application. The salt is pre dissolved in water to a mashed potatoes consistency and th slurry spread on the road. It goes to work right away, and therefore less salt as a whole is used. The other innovation is to make a thinner salt solution than mashed potatoes, and then spray it on the road to pre wet the surface of the asphalt with a salt soultion in advance of a pending snow storm. Most road authorities who do this just do pre-wetting upstream of intersections, where the prevention on ice bonding to the asphalt is most important.
The biggest fly in this whole mix is that Montreal and Quebec City actually use the most salt per lane km of the major road authorities. Quebec has declared that salt management is a provincial issue, and the feds have not got the political gumption to take them on on this issue, so salt management in the whoe country is impacted -as in - 'Well, if you won't bust those guys, then why should I be trying harder.'
One of my companiy's subsidiaries who shares our floor does all sort of environmental consulting, and a couple of the guys I work with on this floor deal with these issues all of the time.