WHEN the first severe cold weather appears this winter Hampshire County Council's winter maintenance team is set to swing into action.

The team is on standby with 15,000 tons of rock salt ready to use on the 42 'priority one' routes which carry around 85 per cent of the county's traffic.

Each time there is a 'salt run' it costs the county council £22,000.

In an average winter, temperatures fall below freezing on approximately one night in three - about 40 nights per winter.

Main roads are routinely salted on a 'just in time' basis when such low temperatures are predicted.

The process works because brine formed when salt mixes with water freezes at a lower temperature than water and thereby prevents the formation of ice.

But salting is not a complete solution as the process loses effectiveness at minus five degrees and has almost no effect when the road temperature is lower than minus 10.

Salting should not be regarded as a green light to drive as though conditions are perfect.

Councillor Keith Estlin, who is the executive member for environment, said: "People sometimes criticise the county council for salting only selected routes, and they ask why their local roads are not routinely done.

"We have to implement a common salting standard across the county and ensure that the most important roads are the first to be treated. The factors we take into account include the amount of traffic, the number of buses that use the route and the size of nearby schools.

"If there is a prolonged cold snap, we will then salt 'priority two' routes such as single access to villages and schools."