Published: Wednesday, 27th January, 2010 5:01pm

To grit or not to grit

by Helen Sweeny

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When you get up in the morning and can make safe passage on the road to work or school or to wherever you are going did you know that someone somewhere has been monitoring the weather for the previous 24 hours to decide whether the roads need salted or not?

The decision making process has actually become very hi-tec indeed and as was revealed at a committee meeting of the County Council's Transportation and Planning Committee meeting this week, the roads in Westmeath have been salted on all but four nights since the cold snap began back at the end of November.

Senior Engineer Michael Connelly explained that the decision making process now uses a hi-tec base, which contains information up loaded and updated constantly by Met Eireann.

County Council engineers then access this data base which gives them information about the road surface temperatures, air temperature, wind speed and the dew temperature and gives an indication of what time the freeze is likely to begin.

For example the big chill began on Sunday January 24 in Mullingar at 9.30pm but the freeze didn't arrive in Athlone until 2.40am on the Monday morning.

The decision on whether or not to send the gritting trucks out is monitored constantly by the council's on duty engineer and when all the information has been assessed he must then decide; to grit or not to grit and with each outing costing in excess of €10,000 it is not a decision to take lightly.

"The idea is that we get salt on the roads before they freeze and in that way it has the maximum effect," said Michael Connelly.

"In all Westmeath County Council is responsible for 2,300km of roads and of that 462km is salted when temperatures and so on indicate that there is likely to be a freeze.

The on duty engineer will make his decision based on the facts that he has but on occasion we have gone out and driven around to assess what the roads are like.

It's an expensive business and we have nine trucks putting out 100 tonnes of salt on each trip so he has to make sure that the process really is essential."

This year that decision has been taken on 42 nights so far and the council has already spent €350,000 in the period between the end of 2009 and the beginning of 2010. In 2008 to 2009 (the gritting season officially stops in April) the total cost of salting the roads was €410,000 and the average number of nights that the trucks have been sent out is just 35.

The increase in the number of nights the council's trucks have been sent out on the roads meant a few halry moments for staff who had realised that while salt stocks had been heavily depleted, they could little but wait until they could get access to more.

The council had high reserves of salt in October (there were 900,000 tonnes between Athlone and Clonmellon) but the unexpected and prolonged uninterrupted cold spell made short work of supplies.

By the beginning of January the council announced that they only had enough supplies for three more nights but were able to procure more salt from Carrickfergus and make sure that we all had safe roads when we took our cars out in the morning.