Study finds decreased use of heavyweight studded tires following 2004 tax

By: Staff May 13, 2008

ANCHORAGE, AK – The use of studded tires on Alaska roads in winter has been somewhat contentious. It is generally accepted that the tires keep vehicles from sliding on slick roads as often and as far as they would without the small metal protuberances, although there are some who dispute a safety advantage. What is not in dispute is that the studs trash road pavement. The many Alaska paved roads sporting well-worn ruts testify to the studs’ grinding capability. And the larger the stud, the worse the wear.

In September 2003, the state of Alaska began collecting a $2.50 tax on every tire sold in the state, and in the following July, it imposed an additional tax of $5 on tires with heavy-duty studs.

In the meantime, in early 2004, a key UAA study found that studded tires provide an overall benefit to the Alaska economy by reducing the number of accidents and injuries. That study included a survey of studded-tire usage in Anchorage, the state’s largest city.

Now comes a new, follow-up report that shows that the use of studded tires in Anchorage decreased by 5 percent in the years since the previous survey and within two years after the heavyweight studded-tire tax was imposed. The new study’s survey indicates that use of conventional heavy-duty studs dropped by 10 percent over the four years. The use of lightweight studs, meanwhile, increased by 5 percent in the same period.

Hannele Zubeck, a professor of civil engineering at the University of Alaska Anchorage, was an author of both studies. In the present report – a paper published in the conference proceedings of the 8th International Symposium on Cold Regions Development, ISCORD 2007, which was held last September in Tampere, Finland – Prof. Zubeck and her co-author, Lynn Aleshire, an adjunct instructor in engineering, write that the changes in studded-tired usage in Anchorage are “significant (and further) studies are required to monitor future trends in studded tire usage.”

It is not yet possible to say with reasonable certainty that the imposition of the state taxes forced a significant number of Anchorage drivers to cut their use of studs, particularly the heavyweight variety, according to Prof. Zubeck. Additional work may or may not find a direct cause-effect relationship. But what appears to be certain is that drivers are using heavyweight studs less. The effect of this change should result in less pavement rutting; safety effects will remain unknown.