Cherish the support for congestion charges

The introduction of a congestion charge in Stockholm had the intended effect of reducing congestion - even long term. And after the introduction of the charges the public support steadily increased. This success story has attracted extensive interest from cities all over the globe. However, increasing the charges levels in Stockholm and Gothenburg have not had anywhere near the same effect on traffic volumes as the introduction. A worrying sign is also that the public support for the charges fell after the increase in both cities.

When the Stockholm congestion charge was introduced in 2006, it immediately reduced congestion levels. The effect was smaller, but still significant, when congestion charge was introduced in Gothenburg 2013. In the project ‘Innovative Strategies for Sustainable Transport’, funded by Vinnova, Maria Börjesson and her colleagues have investigated the long-term effect of the congestion charges in the two cities, including the effects of the system extension (Essingleden) in 2016 and the increase in charging levels in Stockholm 2016 and Gothenburg 2015.

“We show that the Stockholm system still had the same impact on the congestion levels a decade after its introduction. The reduction in traffic volume across the toll cordon was still roughly 20 per cent”, explains Maria Börjesson, Professor of Transport Economics at the Swedish National Road and Transport Research Institute (VTI).

In particular, the number of privately owned cars decreased over the years, whereas vehicles owned by firms have reduced less. Many find it easier to adapt to the charges as time goes by and life changes, i.e. when changing workplace, moving, getting children etc. Many then find new ways of adapting behaviour to avoid paying the charge.

In 2016, Stockholm raised the peak charge from SEK 20 to SEK 35 though with only a five per cent reduction in the traffic volume.

“A smaller effect was expected because those who easily could avoid paying the charge already left the road when the charges were introduced, and hence those who remained found it more difficult to change behaviour even when the charging levels were increased”, says Maria Börjesson.

For the benefit of lorries

In connection with the increase in 2016, a congestion charge was introduced on the Essingeleden bypass. This led to a reduction in traffic of 6 – 7 per cent, i.e. less of a reduction than that observed to and from Stockholm City centre in 2006. One tentative explanation for the lower effect on the bypass could be that drivers found it more difficult to adapt by changing mode, route, destination or time of day. The reduction of 6 - 7 per cent still resulted in a noticeably reduction in travel time because of high initial congestion levels on the bypass.

The main motive for introducing congestion charges was to improve accessibility and reduce travel times by car for the traffic most beneficial for society. According to the research conducted by Maria Börjesson, the congestion charge is having the intended effect. The increased accessibility has benefitted commercial traffic. For instance, before a congestion charge were introduced on the Essinge bypass, some trucks avoided congestion by driving very early in the morning or late at night. However, the reduced congestion levels following the introduction of the charges on the Essinge bypass implied that more of the trucks shifted to mid-day and peak hours.

The public support for congestion charges has for decades been higher in Stockholm than in Gothenburg. However, the support has also been unstable over time in both cities. Just before the congestion charges were introduced the level of support fell in both cities. Once the charges were in place, the support gradually increased again in both Stockholm and Gothenburg. Despite an increase in support of a congestion charge in Gothenburg, the majority of the city’s residents voted ‘No’ in the referendum. In Stockholm, however, the support continued to increase to over 70 percent. However, in 2016, in connection with a congestion charge increase, the level of support fell for the first time. The support fell also in Gothenburg after the increase in the charging levels in 2015.

Word of caution

The congestion charge in Stockholm once again saw an increase in 2020 which, according to the City Council, is justified by the need for more money for various infrastructure projects.

“A word of caution must be mentioned here. An increase in the congestion charge will probably not have any large effect on the traffic volume. It may well however reduce the public support for the charges. The success story of the Stockholm congestion charges, in terms of public support and reduced congestion, is attracting interest from cities all over the globe. However, this success cannot be taken for granted. It would be unfortunate if Stockholm ended up with the same situation as Gothenburg, where the public support for the congestion charge are lower”, says Maria Börjesson.

Text: Johan Sievers/redakta
Translated by: Semantix AB

This is an article from the magazine VTI aktuellt no. 4–2019 (in Swedish).