Volvo Buses


Why is air and noise pollution in our cities so hard to fix?

In some of the worst affected European cities, air and noise pollution have become major causes of premature deaths. But the problem is complex to address. Experts Kenneth Lillelund and Knud Erik Poulsen explains why and how collaboration, focus on public transport and new technology could prove to be the way forward.
top build paris intersection

Over the past 50 years, urban areas in Europe have continued to grow and today some 72 per cent of all Europeans live in a city or a town. With ongoing urbanisation, millions of Europeans are exposed to harmful levels of noise and air pollution in their daily lives and the associated problems have become increasingly evident.

Every year, air pollution causes some 500,000 premature deaths in Europe. Road noise is estimated to cause hypertension in the same number of people, as well as 43,000 cases of heart disease.

Kenneth Lillelund

“Road traffic is a big contributor to these problems, and we are all contributing, because we all need transportation,” says Kenneth Lillelund, noise expert at the European engineering and consultancy company Sweco

Together with his colleague Knud Erik Poulsen, an air pollution expert, they have more than 40 years of experience in their respective fields. Air and noise pollution are complex issues that demand equally complex solutions which they outline in their report Wholesome air, serene cities – reduced noise and air pollution in urban areas.

Knud Erik Poulsen

“The challenge is that even if cities try to do something about the traffic, it will often be difficult to measure, as the effect will be small compared to the background pollution, such as from surrounding industries and power plants,” says Knud Erik Poulsen.

One example is Paris, where the city has been trying to beat air pollution by regulating traffic. Certain cities in the Swiss valleys have tried to do the same.

“To reduce air pollution significantly it would be necessary to do a number of things. An increased number of electric cars and buses could be one of many steps on the way,” says Knud Erik Poulsen.

Another positive aspect of electrical buses, he adds, is that they would reduce the high concentration of diesel fumes that pedestrians along busy roads are currently exposed to. However, even if all vehicles were replaced by electric vehicles there would still be air pollution caused by particles from tyres and brake systems.

“We must also understand that traffic is only one aspect. Even if you were to remove all traffic it wouldn’t solve the problem of air pollution. Background pollution can account for around 50 per cent of a city’s total pollution,” says Knud Erik Poulsen.

After air pollution, traffic noise is the next biggest environmental problem in Europe’s cities. The first noise mapping in Europe was carried out in 2007 and is repeated every five years. Most of this traffic noise is caused by the contact between the wheels and the surface. This means that decreasing the total number of cars on the roads is crucial in order to make a bigger impact on noise levels in a city.

“Even with electric cars we will have a lot of noise. The best thing to do is to reduce the number of vehicles on our roads and one way of doing that is to increase public transport,” Kenneth Lillelund says.

According to UITP, the international organisation for public transport authorities and operators, there has been a relatively steady growth in demand for public transport since 2000 in the EU, with the majority of public transport journeys undertaken via bus systems. But cars are still by far the most important mode for passenger transport in all EU member states.

“Turning people from cars to public transport means changing people’s lifestyle and that takes time. In the meantime, we will also have to work with better noise insulation for buildings, noise screens and outdoor green areas with low noise levels,” Kenneth Lillelund says.

The vast majority of European buses are also still running on diesel. According to Bloomberg New Energy Finance, in 2017, 1.6 percent of the European bus fleets were electric. So, by increasing the number of buses run on sustainable resources, there is large potential of affecting air and noise pollution in Europe.

Challenges like air and noise pollution however require collaboration on many levels. In general, air pollution has decreased during the last decades, thanks to EU regulations on fuel quality. Even background pollution has decreased, because of stricter EU regulations for powerplant emissions.

“The EU has done a lot of good things in this area. To improve the situation further, we would need a number of additional regulations and changes as well as collaboration between different stakeholders to find new solutions. Personally, I believe that technical advancement and developments will be the primary way to solve air and noise pollution,” Knud Erik Poulsen says.

Related News