Bristol’s air is ten percent cleaner

Clean Air Zone Bristol artwork

Air across Bristol is ten percent cleaner, on average, after the first year of the Clean Air Zone (CAZ).

A new report, covering the first year of the CAZ, sets out how 88 percent of journeys into the zone are now made in compliant vehicles. The operational report will be considered by the Mayor of Bristol and the Cabinet at their public meeting on 23 January.

The Clean Air Zone launched on 28 November 2022, following a direction from national government to Bristol and other cities, to reduce nitrogen dioxide pollution in the shortest possible time.

In the foreword of the CAZ Cabinet report, Marvin Rees, the Mayor of Bristol, said:

Photo of Bristol mayor Marvin Rees

The air that we all breathe is cleaner than it was in November 2022. Nitrogen dioxide pollution is down by ten percent across Bristol and is almost 13 percent lower inside the Clean Air Zone (CAZ). Outside the Bristol Royal Infirmary and Children’s Hospital, nitrogen dioxide is down by around 20 percent. And almost nine in ten journeys through the CAZ are now in compliant vehicles, up from a year ago.

The Clean Air Zone remains a blunt instrument from national government, who take £2 from every £9 charge paid by motorists, but, thanks to the support package that we negotiated from Westminster, it is working. Millions of pounds of support has been paid out to Bristol residents and businesses to help them upgrade to cleaner vehicles.

During the same period, my administration has proudly opened our city’s first new train station in almost a century, with another one on track to open this summer. We have driven forward ambitious plans for the future of transport in Bristol through a transformational mass transit system. We have continued to invest in active travel, completing pedestrianisation schemes inside and outside of the Clean Air Zone. After securing millions of pounds over previous years to retrofit buses in Bristol, these cleaner vehicles have seen passenger numbers rise despite challenges. And despite fears that air pollution might be displaced across the CAZ boundary, it has fallen across our city.

In the face of a national cost of living crisis, where everyone continues to feel the squeeze, footfall in Bristol city centre has stayed steady – even increasing by 16 percent at St Nick’s Market! This is testament to the dynamism and increasing diversity of our city centre’s offer, which will be seen again in just a few weeks when hundreds of thousands of people visit the Bristol Light Festival.

Some people called for the Clean Air Zone to start before we had secured a penny of support to help people to upgrade their vehicles. We were right to keep working for Bristol, including to secure exemptions for over 350,000 journeys in the first four months of the scheme’s operation, to help smooth the transition.

And, while some people have called for a charging Clean Air Zone to cover the whole city, like the majority of fellow Bristolians, I remain convinced that is a road best not taken. The CAZ was never about making money for the council: it was about clean air. If our progress cleaning up our air continues, then, in the not-too-distant future, the CAZ should come to an end.”

Diffusion tubes, which monitor air quality at nearly 170 locations across Bristol, have been analysed in a laboratory. Data from these devices published today shows that the biggest improvements have been seen at:

  • Bedminster Down Road: down 27% (site 418)
  • Hotwell Road: down 26.5% (site 555)
  • Park Row: down 27.5% (site 597)
  • Upper Maudlin Street by the Bristol Royal Infirmary: down 27% (site 665)
  • Merchants Road: down 24% (site 254)

This new report follows a technical interim report from the Joint Air Quality Unit (JAQU) in November 2023, which showed that Bristol had passed the State 1 assessment.

Christina Gray, Director of Communities and Public Health at Bristol City Council, added:

Clean air is important in helping reduce the risk of respiratory issues and infections such as asthma, lung cancer, heart disease, and stroke. Air pollution can also contribute to other health issues like depression.

I am delighted to see that the Clean Air Zone is already making a huge difference to Bristol’s air quality, which will have a positive impact on residents’ health now and in the future.

Our children, grandchildren, and beyond, will benefit from the cleaner air that we are all delivering through changing vehicle use and our active travel.

JAQU’s State 2 Assessment report will follow in summer 2024. This will be their official assessment of the first year of the CAZ in Bristol. Their four stages for determining if a Local Authority is achieving success on clean air are as follows:

  • State 1 – on track to achieve success
  • State 2 – has achieved success
  • State 3 – demonstrated to be maintaining success with measures
  • State 4 – likely to continue maintaining success in the absence of measures

Success is defined by national government and means that the measures put in place, for example Bristol’s Clean Air Zone, are having the desired effect and air pollution will not exceed the annual average legal limit. Once stage four is achieved, the CAZ can be decommissioned.

This report is the first annual publication setting out all data related to the operation of the Clean Air Zone. It also includes figures showing that the proportion of drivers paying the Clean Air Zone Daily Charge on time has risen by around one-fifth, and shows that the number of Penalty Charge Notices needing to be issued for non-payment of the CAZ Daily Charge has fallen by around one-third since its peak. Over its first year, after accounting for operating costs, including to the Department for Transport, the CAZ generated just under £26.4 million.

Visit the council website for more information about the zone, including a vehicle checker and boundary map to help best plan your journeys:

On Clean Air Day in June 2023, the Mayor announced that the council had secured a further £11 million to help support residents and businesses to upgrade their vehicles. He also confirmed that the eligibility threshold was being extended to cover everyone earning up to £30,000 per year.

Financial support is still available for residents and businesses to upgrade vehicles and/or take up our active travel offers: