Early wins for London’s Ultra Low Emissions Zone:

Reading Time: 5 minutes

The world’s first 24-hour Ultra Low Emissions Zone is achieving its aims so far– and progress has been faster than expected, a report released by the City of London has found.

From its kick-off on 8 April 2019 to the end of September, London’s central zone has seen nitrogen dioxide concentrations drop by a third (31 per cent), according to the report, released days ahead of a World Air Quality Conference held in the U.K. capital on Wednesday.

All emissions of nitrogen oxides would have been 31 per cent higher than it would have been if the ULEZ had not existed— and it’s ahead of schedule to meet the 45 per cent nitrogen oxides emissions reduction expected in the ULEZ’s first year.

Reductions in fine particulate matter, or PM_2.5, were more modest: a fall of 13 per cent compared to levels London would have experienced sans the ULEZ.

“These figures prove without a doubt that ULEZ is exceeding expectations, reducing polluting vehicles and cleaning up our lethal air,” said Mayor of London, Sadiq Khan.

“I am determined to stop Londoners breathing air so filthy it is damaging our children’s lungs and causing thousands of premature deaths.

“The ULEZ shows what we can achieve if we are brave enough to implement such ambitious policies,” he said.

In 2010, London’s air pollution caused a range of health problems in the capital that are estimated to have shortened lives by 140,743 years — the equivalent of up to 9,400 deaths, and representing an economic cost of up to £3.7 billion.

Chief Executive of the British Lung Foundation, Dr Penny Woods said: “The success of the Ultra Low Emission Zone (ULEZ) is a fantastic example of the difference Clean Air Zones, that charge the most-polluting vehicles, can make in reducing levels of pollution. We now want to see the ULEZ expanded to every polluted London borough to protect the lungs of every Londoner.

“And critically, we know dirty air isn’t just a problem in London. Most UK cities have illegal and unsafe levels of pollution, which seriously affects the health and quality of life of the millions who have a lung disease and puts children at risk of developing a lung condition.

“That’s why similar Clean Air Zones must be urgently rolled out across the country to protect everyone’s lungs.”

Lending force to message that action on air pollution, climate change and health are inextricably linked, the introduction of the zone caused a 4 per cent fall in carbon dioxide emissions in London’s central zone or a 9,800-tonne reduction, in its first six months, according to preliminary estimates.

Earlier this month, the ULEZ won one of seven C40 Cities Bloomberg Philanthropies Awards lauding “the most ambitious and impactful projects by mayors to tackle the global climate crisis”, beating several other cities to clinch top spot in the category, “The future we want breathes clean air”.

But the ULEZ’s impact began even before it was introduced, from the time of its announcement in 2017, through preparations by people, business and government to comply with the zone, including ending permits for diesel taxis and investments in cleaner buses.

Between that announcement in February 2017 and September 2019, the report found a 36 per cent reduction in roadside concentrations of nitrogen dioxide in London’s central zone.

The report also allayed fears from some quarters that the ULEZ would cause emissions to rise on its periphery, finding that none of the air quality monitoring stations located on the zone’s boundary roads measured an increased in nitrogen dioxide emissions since its introduction.

“Introducing the ULEZ to reduce vehicle related air pollution is already showing marked travel behaviour change in those entering this area of London and reducing vehicle use resulting in large reductions in NO2 emissions,” said respiratory specialist Professor Stephen T Holgate.

“Since NO2 is an index pollutant of traffic pollution at street level, reductions of this order will be highly beneficial especially to those most vulnerable such as the very young and old, and those with coexistent lung and heart disease.

“It is also pleasing to see that such a dramatic behaviour change is not offset by increased vehicles at the ULEZ periphery,” he said.

Authorities in London hope that the report’s findings point to a shift to healthier forms of mobility that support cleaner air.

Nearly four out of every five vehicles now entering the zone meets its emissions standards, and central London witnessed reductions in traffic flows in May and September 2019 of between three and nine per cent when compared to 2018.

“The early evidence suggests that the ULEZ is not only encouraging people to use cleaner private cars, but also to use more sustainable alternatives such as walking, cycling and public transport,” said Transport for London’s Director of City Planning, Alex Williams.

The report acknowledges that the ULEZ is one of many policies that have bearing on air quality in London, with other policies including the London-wide Low Emission Zone for heavy vehicles and progressively tighter EU-wide exhaust controls for new vehicles.

But it also brought out local government limitations to improving air quality.

While road transport is the largest single source of particulate matter in London, accounting for about 30 per cent of emissions, over half of its PM_2.5 emissions come from outside of London — that is, regional and non-UK sources.

A large proportion of PM_2.5 comes from wood burning — whose regulation sits beyond the jurisdiction of the city government — and a growing proportion of road transport PM_2.5 emissions come from non-tailpipe emissions, like road wear, re-suspension of road dust, and tyre and brake wear.

A 2017 report found that all Londoners were exposed to PM_2.5 concentrations that exceeded WHO guideline values for the pollutant, putting them among the 9 in 10 people in the world who breathe unhealthy air, the majority of whom are in developing countries in Asia and Africa.

The 2017 report also found that “if PM_2.5 ­reduction measures within the Mayor’s Transport Strategy and London Environment Strategy are accompanied by co-operation on a national and international level, the guideline limit is achievable by 2030.”

Its findings were reinforced by another report released this week, which confirmed London’s capability to meet its commitment of achieving WHO guidelines for PM_2.5 by 2030 — but it could only do so if given additional powers and measures.

The City’s commitment is made in the London Environment Strategy and as part of its participation in BreatheLife; in 2017, London became the first megacity in the world to join BreatheLife and commit to reaching WHO guidelines on fine particulate air pollution.

“I now hope the Government will match my ambition and amend their environment bill to ensure it has the legally binding WHO-recommended limits to be achieved by 2030 that we need to protect public health,” said Mayor Khan.

Air quality challenges are certainly not confined to London, and the UK is struggling with high levels of nitrogen dioxide emissions, prompting local authorities around the country to follow the capital’s lead.

In September, city leaders across England called on the national government and private sector to spend £1.5 billion on a ‘national network’ of 30 Clean Air Zones, which could see £6.5 billion in economic returns.

Read the press release: ULEZ reduces 13,500 cars daily & cuts toxic air pollution by a third

Read the report (PDF): Central London Ultra Low Emission Zone – Six Month Report

Banner photo by Harry Mitchell_AP Images for C40