Final Results of Road Traffic in Winter Project: Socioeconomic Effects of Winter Maintenance and Studded Tires

Abstract

Finland is a sparsely populated country where the road network provides access even to the most remote areas of the country. All public roads maintained by the Finnish National Road Administration (FinnRA) are kept in good condition day and night throughout the year. Sodium chloride is the main substance used for chemical deicing; sanding is used only on roads with little traffic. In Finland the use of studded tires began in the early 1960s. Finland is the leading country in the use of studded tires: in winter, 95 percent of passenger cars have studded tires. The simultaneous use of salt and studded tires causes problems. To solve these problems, FinnRA launched a large research program called “Road Traffic in Winter” to evaluate alternative winter maintenance scenarios for improving social benefits. The project had nine future scenarios, representing permutations of three alternatives each for studded tire use and salting. None of the examined scenarios was more favorable than the baseline situation (current usage). When searching for the socioeconomic optimum, the accident costs become the most important factor, and the accident costs strongly support retention of the baseline situation: the use of salt and studded tires should be continued at current levels despite their drawbacks.