Winter gritting

We are preparing for wintery conditions and this winter we are changing our winter gritting service.

Winter service and gritting

We have reviewed our winter policy to make sure we comply with the new code of practice 'Well-Managed Highway Infrastructure'. This aims to provide a safe, well managed and resilient highway network for all who use it. Our winter policy gives priority to high use roads. Also, roads that access community facilities, such as hospitals, schools and shopping centres.

The winter service sees a move from specific guidelines to a risk-based approach. Appropriate risks are determined from a wide range of evidence. The priority for road gritting is based on route hierarchy and level of use. Main roads will be gritted before other routes. Before, the Council’s gritting programme was based on custom and practice with no clear rules for the selection of routes.

We cannot grit the whole of the road network in Calderdale, due to the time and cost involved. At the moment, we grit over 600km of roads in the Borough. Other routes will be added after extra gritters have been brought in and we have solved some access issues.

The review included checking what routes can be reached by gritters (access to some roads is narrowed by parked cars). Also, that a safe turning circle is available for the large gritting vehicles.

Other arrangements are being looked in to for roads that are too narrow for gritters to access. This may include the use of the Council’s Safer, Cleaner, Greener service fleet.

If you want to know how we decide where and when to grit, view the gritting infographic.

Download the gritting infographic

In severe weather, snow clearing work is done with the following priority:

  1. A roads;
  2. B roads;
  3. remainder of the priority network.

Clearing and removing snow from roads depends upon the amount of snow and the conditions at any particular time.

Grit bins

Over 600 salt bins have been checked and replaced where necessary across the Borough. This will help residents keep neighbourhood streets and paths clear of ice and snow. You can report bins that need to be refilled online.

Request a grit bin refill

Please drive with care, to the road conditions and exercise caution during wintery weather.

For more on how you can prepare for wintery conditions, read: PDFBe prepared: stay winter wise [PDF 12787KB] .

Frequently Asked Questions (FAQs)

These have been written in plain and easy to follow English. If they appear to conflict with the gritting policy, the gritting policy takes precedent.

1. When is the Winter Service available?

The winter service runs from 1st October to 30th April with the weather conditions being monitored 24 hours each day.


2. Who do you use to grit the roads?

We use six local contractors based within Calderdale, with the majority of the gritter drivers being Calderdale residents.


3. What is used to grit the roads?

We use 6mm crushed rock salt, we do not use grit. It melts ice or stops it from forming on road surfaces.

This is spread by our purpose-built gritters that have a 'spreader' at the back. This gives an even layer of salt across the road at a controlled rate.

Gritting vehicles can also be fitted with snow ploughs, when needed.


4. When do you grit and how is the decision taken?

We get detailed weather forecasts, daily. These tell us if roads are likely to freeze or if there will be snow. They also tell us the times of day that this could happen. This helps decisions to be made as to if, or when, gritting will be needed.

We get a 36-hour text forecast daily at 6am, 12noon and 6pm, which gives:

  • minimum road surface temperatures;
  • predicted surface conditions;
  • dew points (at the Pecket Well weather station site).

It includes likely risks and hazards, levels of confidence and snow heights. These initial forecasts are supplemented by updates, or further advice as required.

A 5-day forecast is also issued daily. This gives a detailed overview for the next five days, which lets us prepare early for periods of bad weather.

As well as the forecasts, the road network has been thermally mapped. This shows the parts of the roads that are likely to freeze first, in the Borough. These are updated at 6am, 12noon and 6pm and help us to target treatment where it is needed most.

The winter maintenance decision makers review the:

  • text forecasts;
  • thermal mapping;
  • road surface and weather conditions.

They then decide what part of the network, if any, needs gritting.


5. When do you grit the network?

Gritting will take place when:

  • roads may be wet and road temperatures are forecast to be at or below freezing;
  • snow is forecast;
  • the air is moist and a frost is forecast to form on roads below freezing;
  • gritting is usually done before freezing temperatures occur, but falling rain can delay the start. Due to this, roads can freeze until they are gritted.


6. It is freezing outside, why have you not gritted?

The decision to grit depends on two weather factors:

  • the road surface temperature;
  • and potential road surface moisture.

Although air temperature may be freezing, it does not mean that the roads will be.

We have a weather station at Pecket Well. This tells us the current state of the road surface along with:

  • air temperature;
  • wind speed;
  • precipitation;
  • and other factors. 

You may wake up to find frost on your car, but the roads have not been gritted. This is because we decide to grit based on the temperature of roads, not air.


7. Why has the grit not melted the snow or ice?

Salt spread on the roads has little effect on melting snow, on its own. We need vehicles to drive on it to mix the salt with the ice and snow. This creates a saline solution that has a lower freezing point. Only then will the snow and ice melt.


8. Does grit work at any temperature?

In the concentrations we use on our roads, rock salt is less effective at temperatures below minus five degrees centigrade.

9. How long does it take to treat the network

We aim to treat a route in three hours. This is from when the lorry first starts to grit to finishing its route.

Our objective is to finish gritting, where possible, before freezing conditions take hold. Due to the weather, this is not always possible, like when there is heavy rain prior to freezing conditions.


10. How many treatment routes do you have?

We have 20 routes that cover a mix of primary and secondary roads.

We also have four other routes. These cover the highest roads on the primary and secondary networks that are likely to freeze first.

They may need treating when road surface temperature is forecast to be under 10C at Pecket Well. Also, when we have snowfall on high ground only.


11. There is a layer of snow on the road, why did you not grit?

When we grit a road, further snow fall can lay on top of the road. This covers the salt, which makes it look like we have not gritted.

Traffic needs to drive over a gritted road in order to grind the salt and activate it.


12. What width of road can you treat?

Winter service vehicles require a minimum width of 3 metres increasing to 3.5 metres when snow ploughs are required.

We are not able to access roads if vehicles, skips or other obstructions make the road width less than this.

Note: Please park appropriately to allow access.


13. Why do we sometimes see gritters on the road, but not spreading salt?

This can be when gritters are going:

  • to or from the depot;
  • between treated parts of the network;
  • back over a section that has already been, or will be, treated.


14. It is raining, why are you gritting?

This happens when we have rain, but the forecast road temperature is below zero. Here we must treat roads to stop ice forming.

These are tricky conditions, as the rain can wash grit away or reduce how well it works. This can then lead to ice forming.

You may also notice this when we are treating snowfall on our highest roads. This can fall as rain at lower levels, with the chance of ice forming.


15. What happens if emergency services require access to an area?

During icy conditions and snowfall, we respond straightaway to requests for assistance from the ambulance/fire service and the Police. This is on any of Calderdale’s roads and we divert or call out gritters as needed.


Always open first question: 

See also