Salting and gritting - winter road gritting
We spread grit, or more accurately, salt, on roads when freezing is forecast and when roads are damp to melt and prevent ice. We try to do salting before the morning and after the evening traffic peaks, but we work around the clock in bad weather.
We salt just under half of the roads in Central Bedfordshire. Roads carrying the highest volumes, with the greatest risk of accidents or providing key access are given priority.
Priority 0 gritting routes
Roads we will treat in the rare event that resources are not available for treating priority 1 networks. It includes A and B class carriageways, roads serving Upper and Middle schools and the emergency services.
Priority 1 gritting routes
Priority 1 includes:
- all A and B class roads
- most C class roads
- some UC class roads
- busy peak commuter routes
- main peak hour bus routes
- routes to fire stations
- ambulance stations
- most school bus routes
- roads past all Middle and Upper schools
Priority 2 gritting routes
Roads we will treat when the Priority 1 network has been treated and resources are available.
Some town and parish councils provide a local gritting service with the delegated authority from us. You can contact your town / parish council to check if your area is covered.
Trunk roads and motorways
The M1, A1, A421 and A5 are maintained by Highways England. They can be contacted on 0300 123 5000 or firstname.lastname@example.org.
How does grit work?
Grit is actually salt and when the salt is spread across the road it lowers the freezing point of the road surface. This prevents ice forming. Just spreading salt on its own has a small impact but when cars drive over the salt this helps to turn the salt into a brine solution - this is the most effective way of melting and preventing ice.
When we know that snow is coming, we aim to spread a good layer of salt to prevent the road from freezing and snow settling. Salt itself does not prevent snow from settling but the critical factor is the road surface temperature. As each snowflake lands it lowers the surface temperature and it also dilutes the salt solution. This is why heavy snow will settle and then accumulate despite gritting. Traffic is needed to help work the grit into a brine solution.
All of our gritting lorries can be fitted with a snow plough at the front to clear settled snow. The ploughs cannot go right down to the surface of the road because this would damage it, so we still need to grit behind us to help the roads to clear.
How do we decide when to grit?
We grit when road temperatures are predicted to drop below zero and when the roads are expected to be damp. Ice will not form on a dry road in dry air. We receive a forecast from the Met Office specifically tailored to predict road surface temperatures – this differs from other forecasts which usually predict air temperatures. We also use a computer system that collects weather and road information at different sites across Central Bedfordshire.
We monitor this data at regular intervals around the clock and respond accordingly. In severe weather we’ll probably be out gritting, clearing snow and responding to emergencies around the clock. In prolonged periods of bad weather - if our grit stocks allow - we will then start to look at gritting more minor routes and pavements. Sometimes when the roads are too dangerous, our bin crews cannot collect your rubbish and these crews are diverted to clearing snow.