Norfolk County Council planning and transportation's western area team, based at the former Lynn sugar beet factory site in Poplar Avenue, Saddlebow, is ready to turn out at any time of the day or night.

Area manager John Eastgate said each year a winter service plan was prepared after a review in April of how things went the previous winter.

"We get requests each winter for routes to be added to our salting map and we have to assess these to see if we can fit them in.

"The problem is not with money but the capacity of the gritter and the timescale involved," he said.

"In May we start to pull together the plan. It sets out the roads we are going to salt and they are put into routes."

Precautionary salting is carried out on about 1,900 miles of the county's 5,965-mile highway network, with the Highways Agency responsible for covering the A47, A11 and A12 trunk roads.

Mr Eastgate's 12 lorries look after about 390 miles of the network, including the A10, A17, A134, A148 and A149. Lynn's pedestrian shopping area is also covered.

Depots at Sculthorpe and Watton, with salt barns, cover the northern coast and Breckland area, respectively.

"We mirror the district council boundaries, but for efficiency gritters do go across the boundaries on some routes," he said.

Including loading with salt from the giant 3,000-tonne capacity dome at the Lynn site, it takes three hours to cover each route.

If snow comes, efforts are made to clear the same priority routes as for salting.

"But if it becomes too heavy we have to go to much more strategic routes," he said.

Mr Eastgate explained that the gritting lorries cover both sides of the road even though they are going in one direction because of spinner devices which ensure an even spread of salt.

But with snow ploughs fitted, the lorries can only clear one lane in any direction and double the vehicles are needed to cover the same distance.

Some are therefore pulled off minor roads to look after the main routes.

Certain farmers and contractors with snow ploughs are also put on standby to clear back roads in the more remote areas.

"We rely on the goodwill from our men and from other people coming in and helping us," the area manager said.

"These workmen put in a lot of effort and overall they do a very good job.