Last year's air quality values are causing confusion in Germany. While some cities want to stick to driving bans because the data is not reliable due to the Corona pandemic, other cities are seizing the opportunity and abolishing driving bans and environmental zones. You do not attribute the success to the pandemic, but to the mobility concepts of the cities. Is this too hasty?
Images of deserted streets and smog-free skies accompanied us through the lockdown last year. But to what extent was air quality affected by the pandemic? Scientists and politicians alike are arguing about this. The data are inconclusive. While nitrogen oxide levels had indeed declined, particulate matter levels actually increased during the lockdown. Whoever is to blame for the improved air quality, many cities are drawing consequences - and abolishing driving bans.
The situation is particularly favourable for cities where diesel driving bans were threatened. The low nitrogen oxide values from 2020 make these driving bans obsolete in many cities. The unloved driving bans in Wiesbaden, for example, are off the table. According to the government, new bus lanes, more park and ride spaces and additional cycle paths have had an effect. In Hanover, too, there will be no bans on old diesel vehicles, as the German Environmental Aid (DUH) and the city have reached a settlement. This includes a speed limit of 40 km/h on Friedrich-Ebert-Straße in order to further reduce nitrogen oxide levels. Likewise, there will be no more diesel driving bans in Freiburg. District President Bärbel Schäfer sees the rejuvenation of the vehicle fleet towards low-emission vehicles as the reason for the improvement in air quality. According to Schäfer, the measures introduced by the city, such as the 30 km/h speed zone on the B31 and its inclusion in the green environmental zone, as well as the reopening of the Kronenbrücke bridge, also contribute to the improvement in nitrogen oxide levels. This was 36 µg/m³ in 2019, and as low as 30 µg/m³ in 2020. There is also no longer any need to fear diesel driving bans in Heilbronn. DUH withdraws its lawsuit against the city, since the measures for air pollution control, such as the 40 km/h speed zone in the city centre and an improvement of the cycle paths and public transport, have had an effect.
In contrast, the diesel driving bans in Darmstadt's Hügelstrasse and Heinrichstrasse remain in place, even though nitrogen oxide levels had improved here too last year. In Stuttgart and Hamburg, too, no easing of the rules for diesel vehicles is yet in sight, although the opposition is increasingly building up pressure, as the nitrogen oxide levels no longer justified maintaining the bans. However, because of the uncertain data situation due to last year's pandemic, politicians want to stick to the existing rules here to avoid nasty surprises when traffic volumes increase again.
Not only diesel driving bans are hotly debated. Some of the environmental zones active in about 70 German cities are also beginning to falter. In Baden-Württemberg, 2 low emission zones are being abolished at once. The environmental zone in Balingen was already abolished in November 2020 because the nitrogen oxide values had improved considerably. According to forecasts, the abolition of the zone would have increased nitrogen oxide levels by no more than 10 per cent to an annual average of 31 µg/m³ in 2020. The reduction in traffic due to the pandemic may have helped somewhat here as well. However, the speed limit of 30 kilometres per hour in the Endingen through-road remains in place, as this also contributes to noise reduction, according to Lord Mayor Helmut Reitemann. In Schramberg, too, the environmental zone will be abolished in 2021, according to District President Bärbel Schäfer. In fact, a clear trend of reducing nitrogen oxide levels was observed here even before the pandemic. In 2012, this was still at 52 µg/m³, in 2016 the limit value was complied with for the first time at 40 µg/m³. Since then, it has decreased to 36, 34 and 31 µg/m³ in 2017, 18 and 19 respectively. Most recently, it was 27 µg/m³ in 2020.
In Düsseldorf, Mayor Stephan Keller announced some time ago that the three active eco-lanes would be abolished in March 2021. These caused congestion and thus bad air. A new concept envisages gateway traffic lights to reduce traffic in the city centre. In addition, more cycle lanes are to be built and temporary 30 km/h speed zones introduced. Only the eco-lane on Prinz-Georg-Straße is not to be simply given back to road traffic. Instead, a cycle path will be created here that can also be used by public transport.
It remains questionable why many cities are primarily concerned with nitrogen oxide levels in their decisions. These are usually decisive for diesel driving bans, as old diesel vehicles in particular emit nitrogen dioxide. However, the environmental zones are generally also intended to ensure compliance with particulate matter levels. Since these are still high, abolishing the zones could certainly lead to problems.
Whatever one's view of driving bans, the chaos shows that last year's air quality values can be interpreted in a variety of ways. As a result, they justify political decisions that could not be more different.