Doing it as a snow melter would be impractical, it would use tons of heat and energy on an almost constant basis. In theory it is a good idea but one good hit of snow from a snow plow and you would be back to square one.
This is one of those ideas that looks good on paper but in practice gets abandoned rather quickly.
Only needs to be heated to +3°C as a snow-melter, and only during snow or freezing rain. The frost depth in Toronto is around 1.2 m by early February.
BTW. Some GO Train stations use a snow-melter system on their platforms. See link.