Clean Air Zones – Leeds out but Birmingham and Bristol forge ahead.
As both charging and non-charging Clean Air Zones (CAZ) were announced before the pandemic, plans for their introduction have changed. Intended to reduce air pollution, and the ensuing respiratory illnesses, they are designed to discourage motorists from driving into cities. However, 2020’s national lockdown gave us an ideal opportunity to see for ourselves how much of an influence the motorcar has over air quality in urban areas.
According to this fascinating report, from the School of Environmental Sciences at the University of Liverpool (**https://link.springer.com/article/10.1007/s11869-020-00937-0**), certain pollutants declined between 37% and 63%, but (somewhat worryingly) other harmful gases increased. While there is no doubt that reducing the number of vehicles (and improving traffic flow) in clogged cities will improve air quality, focusing on a sole perpetrator is likely to yield disappointing results. The report acknowledges this rather problematic issue.
Therefore, it is not unreasonable to presume that CAZs are unlikely to deliver the expected high levels of real-world air quality improvements that their supporters hope, unless other causes of air pollution are targeted at the same time.
Leeds has cancelled its CAZ, after completing a joint review by its city council and the government. When re-evaluating the city’s air quality in August 2020, it found between 80 and 90% of large vehicles used cleaner Euro VI engines and almost half of its taxis were either hybrid, or electric. According to the authorities, those factors reduced the legal limits of air pollution below the required limits, since the last measurements were taken in 2018. Yet, it is thought that a CAZ could be considered again, should pollution levels breach legal limits once more.
Meanwhile, other CAZs that were postponed have confirmed introduction dates. Bath’s CAZ will commence from March 15th, 2021, Birmingham, from June 1st.