Removing Snow in Montreal
Based on James Campbell and Andre Langevin, “The Snow Disposal Assignment Problem,”
Journal of the Operational Research Society, 1995, pp. 919-929.
Snow removal and disposal are important and expensive activities in Montreal
and many northern cities. Although snow can be cleared from streets and sidewalks
by plowing and shoveling, in prolonged subfreezing temperatures, the resulting
banks of accumulated snow can impede pedestrian and vehicular traffic and must be
To allow timely removal and disposal of snow, a city is divided up into several
sectors, and snow removal operations are carried out concurrently in each sector. In
Montreal, accumulated snow is loaded into trucks and hauled away to disposal sites
(for example, rivers, quarries, sewer chutes, surface holding areas). The different
types of disposal sites can accommodate different amounts of snow due to the
physical size of the disposal facility. The annual capacities for five different snow
disposal sites are given in the following table (in 1,000s of cubic meters):