In order to maximise the social welfare from resources expended on infrastructure, two aspects are in focus. The first is to build new roads, bridges etc., once the aggregate benefits of an investment exceed the resources allocated to construction; the second is to charge for the use of existing assets according to the social marginal costs emanating from their use. The focus of this study is on the second issue.
This study has estimated the marginal costs for road reinvestment using information at a very disaggregate level. One robust result of the analysis is that not only heavy vehicles, but also light vehicles, affect the periodicity of resurfacing activities. Most probably, this is the consequence of the use of studded tires in a country with freeze-thaw cycles.
While both trucks and cars have an impact on the timing of resurfacing, the analysis has not provided any indications of that time per se is of separate relevance for life length. One possible reason is that vehicle wear triggers the resurfacing activity long before the passage of time has any effects on the aging of the road surface.
It is also important to acknowledge that the heterogeneity across sections of roads is only partly characterised by available data. In particular, very little is known about the quality of the road beneath the top layer. The “life” of roads that are classified in the same way and are used by a similar number of vehicles may still differ substantially, due to the fact that they are built on solid rock, or on sand, or on materials that are not robust during the spring thaw. Constructions may also differ simply because of different skills of the construction teams or because the sub-structures built long ago had a lower standard than today. While information is abundant about surface structure, the variation in substructure still leaves the analyst with only partial information of what drives quality deterioration.