Winter News

Winter Service Information

Keeping traffic on the move - our aim

We aim to help main road traffic move safely and freely in wintry conditions by spreading salt at the most effective times.

Responsibilities

Although we have no statutory obligation to salt roads, Department for Infrastructure (DfI) receives sufficient funding to salt main routes in accordance with our aim.

Which roads are salted

• We focus our resources on roads carrying the most traffic.
• A schedule of salting routes has been drawn up covering the main through routes carrying more than 1,500 vehicles per day.
• Other roads carrying more than 1,000 vehicles per day may also be included if they are in hilly areas or there are other difficult circumstances.
• Special allowance is made for school and other buses by a weighting factor. For example, a 40-seater bus is counted as 40 vehicles
• Almost 7,000 km (4,300 miles) of roads are salted which is 28% of the length of the road network and salting it costs £4.5M in an average winter.
• This caters for 80% of all traffic. To cover 90% of traffic the length of roads salted would be doubled, at twice the cost.
• On more lightly trafficked roads, salt boxes or grit piles may be placed at hills, bends or junctions for use by the public.

When does salting take place?

DfI duty controllers are on call 24 hours a day in each of our 4 divisions. Based on all of the forecast data and local knowledge, they will make the appropriate decision for their local area.

The season usually lasts from early November to late March but winter service will be provided outside this period if necessary.

Salt is not normally spread

• During heavy rain, as the salt will simply be washed away.
• On dry roads, since ice will not form even if the temperature falls below zero.
• In the middle of the night, because there is not enough traffic to turn the salt and ice into solution and make it effective.

The best advice to motorists is given in rule 230 of the Highway Code for Northern Ireland:

"When driving in icy or snowy weather:

• drive with care, even if the roads have been treated
• keep well back from the road user in front as stopping distances can be ten times greater than on dry roads
• take care when overtaking vehicles spreading salt or other de-icer, particularly if you are riding a motorcycle or cycle
• watch out for snowploughs which may throw out snow on either side
• do not overtake them unless the lane you intend to take has been cleared
• be prepared for the road conditions to change over relatively short distances
• listen to travel bulletins and take note of variable message signs that may provide information about weather, road and traffic conditions ahead"

"Drive extremely carefully when the roads are icy. Avoid sudden distractions as these could cause loss of control. You should:

• drive at a slow speed in as high a gear as possible; accelerate and brake very gently
• drive particularly slowly on bends where loss of control is more likely
• brake progressively on the straight before you reach a bend - having slowed down, steer smoothly round the bend, avoiding sudden actions
• check your grip on the road surface when there is snow or ice by choosing a safe place to brake gently - if the steering feels unresponsive this may indicate ice and your vehicle losing its grip on the road (when travelling on ice, tyres make virtually no noise)"

Heavy snow conditions

• If roads become impassable due to deep snow, we will divert all our resources to clearing routes in priority order.
• DfI will initially clear the Trunk Road Network.
• The remainder of the salted network will then be cleared of snow.
• Once the salted network has been dealt with, resources will be directed to the rest of the public network.

Can ice-free roads be guaranteed?

• Ice-free roads cannot be guaranteed.
• The Met Office can only guarantee 80% accuracy in their forecasts. Northern Ireland has a high proportion of marginal nights when temperatures are very close to zero. This makes it more difficult to forecast than in colder countries where frost is more certain.
• It takes up to 3½ hours to salt a route, so your journey may start or end on an un-treated section of the route.
• If it rains, the salt will be washed away and the wet surface may freeze if the temperature falls below zero.

To download our Winter Service public information leaflet, click the link.

Seasonal advice for driving in winter

The links below provide advice to motorists when driving in wintry conditions.

• https://www.theaa.com/driving-advice/seasonal/winter
• https://www.nidirect.gov.uk/publications/driving-adverse-weather-conditions-leaflet

Met Office

The Met Office website provides a guide to severe weather warnings and useful information on preparing for weather conditions.