Gritting

In cold periods during winter, rock salt is spread on sections roads and footways around the borough. Salt works by mixing with any moisture on the surface or in the air, creating a saline solution. This solution lowers the freezing point of water preventing the formation of ice. After spreading, the process of mixing with moisture and turning to a saline solution is aided by being crushed by passing vehicular traffic, or by footfall on pedestrian areas.

When there is reduced traffic, salt sits on the surface in larger granules which can take longer to mix with moisture and become an effective de-icing solution. Where possible salt is spread prior to snowfall. As the snow lands on the surface it begins to melt onto the salt granules eventually turning them to solution, helping to reduce the accumulation of snow, and forming a barrier reducing the likelihood of the snow freezing on the surface.

Where the snow falls at a faster rate than the salt can mix with the moisture, greater accumulations of snow will occur. Deeper snow will have to be ploughed away on roads or cleared on footways. This is made easier when pre-salting has taken place.

Salting on settled snow has limited benefits, as the salt will only become effective as it mixes with the snow and turns to solution which can take a considerable time as often vehicular and pedestrian traffic is reduced limiting the crushing process of the salt and hence the saline solution needed to melt the build up of snow.