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Making short work of long traffic jams
Research

Making short work of long traffic jams

‘Supersmart road-pricing’ is an intricate solution for traffic jams.

7 minutes
16 September 2020

The problem of traffic jams in Belgium is a many-headed monster that appears impossible to slay. A ‘supersmart’ variant of road-pricing might be the weapon to win the fight.

Countries are proud to have some titles, while it would rather be rid of some others. For example, Belgium has the unenviable reputation of being the traffic jam champions of Europe. Eternal bumper-to-bumper traffic is not only a waste of time, but also money, Professor of Transport Economics Stef Proost at the Department of Economics and co-founder of the spin-off Transport & Mobility Leuven says. “We recently calculated how much the traffic jams cost us per year, and the result was a whopping 3.25 billion euro per year.”

It is a hefty sum, but according to Proost it is far from exaggerated if you take all of the relevant factors into account. “You have to look beyond all of the hours lost in traffic jams. The inconvenience of attempting to avoid the worst traffic jams and arriving at work too early or too late as a result also imply a cost. Economists have scientific methods of expressing that ‘schedule delay’ in monetary terms.”

Furthermore, traffic jams inhibit a good match on the labour market. “Many of the highly educated make the following reflection: Why would I go and work on the other side of Brussels? It’s just going to be miserable on the road every day. So they take a job closer to home that is not as well suited to their skills. To take an extreme example, a programmer goes to work as a shelf-stacker at the local supermarket, and is thus far less productive for the economy.”

In order to avoid traffic jams, many of the highly educated take a job closer to home that is not as well suited to their skills.

Counterproductive

How can we tame the traffic jams? A first step is breaking down the complex problem in a simple way: traffic jams occur because many people want to be in the same place at the same time and use the same roads to get there.

The last part of the problem might be solved by convincing as many drivers as possible to take public transport. That might help for connections between big cities, Professor Proost says, but it is not a miracle cure. “Lower fees and higher frequencies might attract more train passengers, but studies show that only 10 to 40 percent of them are converted drivers. Most of them are people who want to do a day of shopping or take a trip to the coast. In other words, it is not a cost-effective solution. In any case, the costs of public transport in the rush hour are very high. For example, you have to invest in extra rush-hour trains, which will drive back and forth to Brussels once per day, as it were, and stand idle the rest of the time.”

Could traffic jams be solved by by convincing as many drivers as possible to take public transport? That might help for connections between big cities, Professor Proost says, but it is not a miracle cure.
Could traffic jams be solved by by convincing as many drivers as possible to take public transport? That might help for connections between big cities, Professor Proost says, but it is not a miracle cure.

Might a switch to cycling or more frequent work from home be a solution? “Bicycles are indeed a good and sustainable alternative,” Professor Proost says. “Electric bicycles offer an action radius of ten to twenty kilometres. And bicycle equipment and infrastructure continue to get better all the time. As far as working from home is concerned: the corona crisis has led to more people being believers. On the other hand, you cannot underestimate the importance of ‘informal talk’: knowledge that really matters is often not to be found on the internet but in conversations with your colleagues, as we will rediscover. All in all, I estimate that working from home might replace approximately 20 to 30% of commuter journeys.”

Whatever the case may be, these solutions will not solve the problem of traffic jams. They may reduce the traffic jams to some extent, but in the long term, they will be counterproductive. “You will suddenly see that motorway journeys go more smoothly and think ‘maybe I’ll go and work in Brussels more often’. In other words, a reduction in traffic jams attracts additional traffic; the scientific literature has demonstrated this. It is called the ‘law of eternal congestion’.”

Tariffs gradations

To counteract this law, you have to intervene in the dynamics of traffic jams themselves. The creatures of habit that rush-hour commuters are, need to be stimulated to change their behaviour. One might think of kilometre charges, such as have been introduced for freight lorries in this country. Such charges could be higher during the rush hour than during off-peak periods. In other words, a system with two fees, the so-called ‘smart road-pricing’.

But to be really effective, you need a more intricate system, Professor Proost argues. Along with his colleague Bruno De Borger (UAntwerpen), he advocates a ‘supersmart’ version of road-pricing. The idea is that you direct the departure times of car drivers by imposing a tax that varies within the rush hour period itself. At very busy times, the toll is highest and at quieter times you would pay less. This is a way of staggering departure times over a longer period and making sure that the number of cars entering the road system never exceeds its capacity.

The idea is that you direct the departure times of car drivers by imposing a tax that varies within the rush hour period itself.

Examples abroad show that this can work, Proost says. “Stockholm and Gothenburg, for example, have such systems of tariff gradations: if you drive into the city at six o’clock, for example, you pay 15 Swedish crowns, at half past six you pay 30 crowns, at seven 45 crowns, etc. And there are several other gradations during the rush hour. This measure was introduced as an experiment following a request from the Green party, in exchange for supporting a minority government, but everyone is now convinced that it works. Singapore has a similar system with – and this is also important – fees that can be adapted flexibly by the road administration without any political wrangling getting in the way.”

Major advantage

The supersmart part of the system is that the total cost of a trip does not increase for anyone. If you want to be at work on time, the cost of the traffic jam is replaced by the toll. If you are prepared to arrive a little earlier or later, there will be a ‘schedule delay’ cost, but you will pay a lower toll or no toll at all, and there will be no traffic jam cost. The total cost per trip will thus be the same, but it will be divided differently. The major benefit will be no more traffic jams.

Furthermore, the revenue from the toll could be given back to drivers. “This could be done by lowering the tax on car ownership, for example,” Professor Proost says. “This would be one way of getting drivers – and the politicians who have to implement road-pricing – on board. There are also variations to the system. For example, drivers of low-emission cars could receive more money back.”

What kind of concrete numbers are we talking about? This depends on the congestion problem you are looking at. In the ideal version of supersmart road-pricing, Proost and De Borger envision quite a high toll for those who want to arrive on time in Brussels, for example: 6.66 euro. But they also advocate a ‘light’ version that is more acceptable or ‘sellable’ for politicians and policymakers, with a maximum toll of 3.33 euro. If one were only to introduce supersmart road-pricing in traffic jam-sensitive areas – which the researchers advocate – the revenue in Flanders would amount to 400 to 900 million euro in Flanders. This could be used to reduce the annual road tax by 100 euro, down to an average of 320 euro per car.

“It ought to be clear that the intention of introducing road-pricing is not to generate income, but to manage excessive traffic and reduce traffic jams,” Professor Proost says.

“The intention of introducing road-pricing is not to generate income, but to manage excessive traffic and reduce traffic jams.”
“The intention of introducing road-pricing is not to generate income, but to manage excessive traffic and reduce traffic jams.”

Listen to the expert

Employees must be able to count on the necessary flexibility from employers, crèches and schools, so that they can go to work outside the rush hour. But Professor Proost does think that there is a lot of goodwill. “I have spoken to many employers. Of course they also see that the traffic is completely blocked and they also want road-pricing to be introduced.”

But are political minds ready for the change? Previous governments all included studies of road-pricing in their policy statements, but always postponed actually implementing it. In Flanders, the idea has again been shelved, but there is more interest in the Brussels Capital Region.

According to Professor Proost, the advantages of the system are so obvious that its introduction is only a question of time. Who knows, perhaps the corona crisis might be a catalyst, he says: “Over the past few months, politicians have demonstrated that they are able to listen to experts in virology and epidemiology. Perhaps they will start doing so more often in other policy areas as well…”

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