Although we receive detailed and regular weather reports some conditions are particularly hard to predict, such as early morning frost, and ice can form on the road before gritting is completed.
Gritting involves spreading rock salt on the roads to prevent ice forming and, during heavy snowfalls, snow ploughs may be used to clear snow.
Salting is done when it is not raining to avoid the grit being washed away. If rainwater freezes quickly ice can form before our teams have completed their routes.
If rain turns to snow during rush hours it is very difficult to salt routes because of the level of traffic.
In addition, rock salt has a limited impact on icy surfaces where the temperature drops below 8 degrees centigrade.
If you leave a car parked on the road please ensure our vehicles have enough space to pass by - at least 3 metres.
Myths
Here are the facts about gritting - despite what some popular myths would have you believe!
Once the gritter has put salt on the road all ice will melt
This is not true! Spreading salt on the road is only the start of the de-icing process. Movement of salt around the road by traffic is essential to complete the process. Overnight, when traffic levels are low, roads can remain icy for some time.
Spreading salt on fresh snow will melt it more quickly
This is not true! Salt only effectively melts snow when it is less than 40mm deep and traffic can move the salt around. It is essential we plough fresh snow to a depth of 40mm before spreading salt.
No matter what the temperature salt will melt the ice
This is not true! In the concentrations we use on our roads salt does not melt ice below minus 8 degrees centigrade and is less effective at temperatures below minus 5 degrees centigrade.