New monitoring technology and more accurate meteorological forecasts are being employed by Lancashire County Council to allow them to predict extreme weather and better prepare the roads.
Councillors are set to be told how the new technology is being used to more accurately decide when the county's roads need to be gritted, with a report to Lancashire County Council's cabinet next week set to outlines how highway teams can predict with a high degree of certainty when road temperatures will fall near freezing.
The county's highways teams currently monitor the weather throughout the winter to ensure that the roads are gritted whenever a freeze is forecast, with a safety margin built into the decision-making process to take account of any variation between weather forecasts and actual road surface temperatures.
"Our gritting crews are on standby 24/7 from October to April, and when low temperatures are forecast we grit the roads as a precaution before frost forms or a weather front arrives, usually during the evening or early hours of the morning," said County Councillor Keith Iddon, cabinet member for highways and transport.
"The decision on whether to send out the gritters is taken by experienced staff according to the most accurate information available on local weather conditions, as well as data from roadside monitoring equipment around the county," he added. "This method is very well developed, allowing us to differentiate between conditions on each of 45 routes, so that we only grit those that we need to."
The current policy is to grit the roads when temperatures are due to fall to 1.0 Celsius or below, with cabinet to consider a proposal to reduce this to 0.5C. The report to the cabinet meeting is due to take place on August 9th outlining how more reliable forecasts and accurate roadside monitoring stations mean the lower margin of error could be safely introduced.
The results of a study into the council's winter gritting operation over the past two years has found that 894 individual routes were treated when temperatures actually stayed above freezing. Adopting the lower threshold would have saved around £220,000, reduced salt usage by 3,600 tonnes, and reduced downtime by ensuring staff involved in the gritting operation overnight were available for other daytime duties.
"Our climate means that conditions are often marginal, with road temperatures due to drop near zero at some point over the night, which is why we build in a small margin of error," Cllr Iddon said. "I will ask cabinet to carefully consider this proposal as officers' advice is that we could reduce this from 1.0C to 0.5C without compromising safety, while making significant savings in cost and resources."
The report says that the recommendation to adopt the 0.5C threshold would still allow for any errors in the forecast, and that the council's forecast provider would alert highways officers if it changed for the worse and a review of practice used by 12 other councils found that some use the same 1.0C intervention level as Lancashire while others only send their gritters out when temperatures are forecast to reach zero.