The Oslo and Bergen toll rings and road-building investment – Effect on traffic development and congestion

When the toll rings around Bergen and Oslo were established in 1986 and 1990, respectively, they were part of major schemes to speed up road investments. In Oslo, 20% of the revenue was allocated for investments in public transport, while in Bergen, third the size of Oslo, investments were exclusively for road transport. This article focuses on how city size and public transport policy may influence effects of infrastructure investments on car traffic development and congestion. Oslo, having one million inhabitants, experienced moderate growth in car traffic, and public transport traffic volumes experienced a stronger growth than the national average. Still, congestion levels were only slightly changed. The smaller city Bergen, however, experienced a strong increase in car traffic and a strong decrease in public transport traffic. Despite the strong growth in car traffic, increased road capacity still seems to have resolved congestion problems, at least during the period under study. The result seems to indicate that in smaller cities increased road capacity might relieve congestion even if road traffic increases. Urban sprawl seems to be a major factor behind increased car traffic in both cities.