Winter Driving

Providing the Winter Maintenance Service.

What Does it Involve?

There are two elements to Winter Maintenance:

• Precautionary treatment -salting in anticipation of a wet frost or snow.
• Removal of snow and ice - by ploughing, snow blowing and salting.

The "season" lasts roughly from November to March.

How is it Arranged in Lancashire?

Motorways and Trunk Roads are looked after by the Highways Agency for Central Government.

Most other urban roads are looked after by District Council on behalf of the County Council.

Most other rural roads are looked after by the County Council

What is the Scale of the Operation in the County

In severe weather, up to 100 gritters can be turned out as follows:

In addition, the County Council has 25 snowploughs and makes arrangements with farmers to assist where appropriate.

Maximum salt storage is 25,000t and this is regularly topped up during the winter. In an average winter the service costs about £3M to run.

Weather to Salt

Delivery of the service depends on the weather forecast and accuracy in marginal conditions is paramount. An error of 1°C when the temperature is around zero matters a great deal whilst at 5°C it is largely irrelevant.

On average, forecasts are 87% accurate and in most winters this could mean that there are 10 days when frost is not forecast, but actually occurs. There are also significant local weather variations that are difficult to forecast.

Weather forecasts are only a guide and our own local expertise is vital.

How is Forecast Data Disseminated?

The County Council uses 11 road weather stations collecting local meteorological data that is sent electronically to the forecast provider. This data is applied to the forecaster's models to give local forecasts for the County's four forecast areas. Forecasts are then passed electronically to operational staff to assist them in making the decision on what to do.

Real time data is available 24hrs a day, throughout the winter period to monitor conditions, and a county duty officer keeps a watching brief for significant changes in conditions during evenings, weekends and holidays.

What Sort of Arrangements are Made?

Precautionary salting may be carried out during the evening or the next morning (from around 5am), preceded by an inspection in marginal conditions. Gritter crews are normally held on home standby and if snow is forecast, are brought in early to salt prior to the snowfall and then to deal with problems as they arise.

In emergency conditions considerable additional resources are brought in.

Treatment Priorities

Priority 1

County Motorways
Principal (A) Roads

Priority 2

All "B" Roads
Other Roads:-
- between or through large centres of population
- serving hospitals, ambulance and fire stations
- leading to main centres of employment and on important commuter routes
- leading to important industrial and military establishments
- Single access to villages

NOTE: Estate and other minor roads without appreciable gradients are not treated in Lancashire

The above is a list for precautionary treatment which comprises more than 1/3 of the county maintained road network. Those roads to be treated are indicated in green on the maps, but their treatment at all times cannot be guaranteed. It would be extremely expensive and largely ineffective to treat the whole road system. The list is extended when snow and ice persist.

How Can We Possibly Get it Wrong?

No matter how accurate the forecast is there may be situations where we cannot respond:

• On a wet night followed by rapidly clearing skies, salting will normally start after the rain has stopped to avoid salt being washed away. Temperatures may fall by as much 5°C per hour and the wet roads may well freeze before the gritter has been able to salt them.
• "Dawn frost" - This occurs on dry roads and involves the development of early morning dew which falls on cold road and freezes on impact. It is impossible to forecast with any accuracy where and when it will occur.
• Rush hour snowfall - when rain turns to snow coinciding with the rush hour. Early salting cannot take place as it would be washed away and gritters cannot make progress due to traffic congestion.

About Rock Salt and how it works

We use rock salt responsibly as it comes from a non-renewable source and in high concentrations is environmentally unfriendly and can damage vegetation.

Salt spread rates vary from 10grams/m² for precautionary treatment to 40grams/m² on snow.

Salt works by turning the ice or snow surrounding each salt granule into a saline solution. The action of traffic is essential for salting to be effective by moving the salt granules around and eventually melting all the ice. On more lightly trafficked roads the surface will remain icy for some time after salting and it must be stressed that the spreading of salt does not mean that the road surface will instantly become ice-free.

Drivers should always drive with caution whether the road has been salted or not.