How Cities Clear the Snow

AFTER THE STORM: HOW CANADIAN CITIES CLEAR THE SNOW A. For many Canadian municipalities, snow removal is one of the largest items in the yearly budget. A single major storm can require hundreds of workers and vehicles operating around the clock. Most cities do not try to clear every street at once. Instead, they follow a priority system: main roads, bus routes and streets leading to hospitals and fire stations are ploughed first, followed by collector roads and, finally, quiet residential streets. This is why people who live on side streets sometimes wait a day or more after a storm before a plough arrives. Cities with heavier snowfall typically keep a larger fleet of ploughs, while those with milder winters may hire private contractors when storms arrive. Crews often work long shifts, and many cities hire seasonal drivers to help during the winter months. B. Before and during a storm, crews spread materials to keep roads from becoming icy. Rock salt is the most common choice because it lowers the freezing point of water, preventing ice from bonding to the pavement. However, salt becomes much less effective in very cold temperatures, so crews may add sand for traction or mix the salt with liquids that keep working when it is colder. Some cities spray a salty liquid called brine onto roads before the snow begins, which helps stop ice from forming in the first place and reduces the amount of salt needed later. The best mix depends on the temperature, the type of road and the amount of traffic it carries. C. Salt has a hidden cost. As snow melts, the salt washes into storm drains, rivers and lakes, where high levels can harm fish, frogs and other aquatic life. It also damages roadside trees and soil, and it speeds up the rusting of cars, bridges and the steel reinforcing inside concrete. For these reasons, many municipalities now train their drivers to apply only as much as necessary and fit trucks with equipment that adjusts the amount automatically according to the vehicle's speed. Some cities have built covered storage domes so that piles of salt do not wash away in the rain before they are used. D. In the largest cities, simply pushing snow to the side of the road is not enough. After heavy storms, crews load snow into trucks and haul it to special storage sites, where huge piles may remain until late spring. Residents also have responsibilities. Many municipalities require homeowners to clear the sidewalk in front of their property within a set time after snowfall, and parking bans are often declared so that ploughs can reach the curb. Some communities run volunteer programs to help older adults and people with disabilities clear their walkways and driveways. Fines may be issued to residents who ignore sidewalk rules or leave vehicles on the street during a ban.