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Capital of United Kingdom

London is the capital of the United Kingdom and the second largest city in the EU with 8.3 million inhabitants. The metropolitan area has a population of 12 to 14 million. The city is one of the global cities, and is a centre for finance, business, arts, education, and many more. The city generates 20% of the UK’s GDP. London is famous for its underground metro, the Tube, which is the oldest metro system in the world. It also has a dense bus system, with 8,000 buses and 700 bus routes, as well as a tram system with three routes. London has a strong use of public transport but was also able to promote cycling in the last decade.

London has shown effort to tackle its high levels of air pollution over the last years, including by implementing a congestion charge. However, several of these measures were softened after their introduction, a step that the city ranking evaluated very critically.

Overall Grade: C- 71%

Pie Chart 71
  • Graph Reduction Success Local Emissions
  • Graph Low Emission Zones & Bans of High Emitters
  • Graph Public Procurement Clean Cars
  • Graph Non-Road Mobile Emission Sources
  • Graph Use of Economic Incentives
  • Graph Traffic & Mobility Management Incl. Modal Split
  • Graph Promotion of Public Transport
  • Graph Promotion of Walking & Cycling
  • Graph Transparency & Communication Policy


Reduction Success Local Emissions

London experienced a reduction trend of particulate matter between 2005 and 2008 and a further decrease by 2012: PM10 exceedance days at Marylebone Road traffic station decreased from 60 to 27 after an intermediate high of 58 exceedance days in 2011. Accordingly, PM10 annual mean values decreased from 39.1 μg/m3 to 31.1 μg/m3 between 2008 and 2012. PM10 exceedances at Horn Lane, however, increased from 71 in 2009 to 76 in 2013, which shows that London has a very diverse air pollution pattern.

Overall, London has had a trend of 2% per annum reductions in NO2 concentrations in each of the last 6 years. At Marylebone Road station, NO2 concentration decreased from 115.5 μg/m3 in 2008 to 94.3 μg/m3 in 2012, meaning they are far above EU limit values (40 μg/m3).

Other traffic stations like Oxford Street and Brixton Road possibly have the highest officially monitored concentrations of NO2 in the world.

King’s College website on air quality, comment on NO2 concentrations at Oxford Street station (Engl.):…

Low Emission Zones & Bans of High Emitters

In 2008, London introduced a low emission zone (LEZ) requiring Euro III standards for particulate matter for heavy goods vehicles greater than or equal to 3.5 tonnes in most of Greater London. The regulations tightened to Euro IV emission standards for particulate matter for heavy goods vehicles and buses, and Euro III for heavier vans and mini buses from 2012. Plans to tighten the LEZ to meet the Euro IV standards for NOx from 2015 have been scrapped for HGVs and coaches, although the municipal bus fleet will still be expected to meet this standard. In 2013, an Ultra Low Emission Zone (ULEZ) was envisaged for 2020, regulating the emissions in an area of about 22 km² in central London. Here, the highest emission standards are planned to be required for all types of vehicles. Final requirements are under consultation. The standards that will be adopted are still uncertain. Furthermore, there have been steps backwards during the past years: plans for the ULEZ have been downgraded from banning pre-Euro 6 diesel and pre-Euro 4 petrol to a £12.50 daily charge for such vehicles. Additionally, up to 30,000 vehicles will be exempt for a further three years from any charges. The ULEZ might officially be approved in spring 2015 at the earliest.

Transport for London information on the Ultra Low Emission Zone (Engl.):…

Public Procurement Clean Cars

All buses must comply at least with Euro IV standards. From 2015, Euro IV is also required. By the end of 2015, the city plans to have retrofitted 900 buses with NOx filters and to have replaced 900 old buses by buses to meet Euro VI standards. Additionally, 1700 new hybrid buses will be purchased by 2016.

Regarding the taxi fleet, London has set requirements that all taxis new to licensing must meet at least Euro 5 standards and must not be older than 15 years. This age limit has removed over 6000 of the most polluting taxis since 2012. A tightened age limit of 10 years is envisaged for 2020 across London. Although positive actions are undertaken regarding the taxi fleet, these 23,000 vehicles are still responsible for about 35% of central London’s PM10 emissions and around 15% of NOx emissions. NO2 emissions from the newest taxis, which are all diesel, equal or exceed those from the oldest models.

Non-Road Mobile Emission Sources

A best practice guide for construction and demolition with recommendations on how to reduce dust and soot emissions from construction and demolition work was published in 2006 and substantially updated in 2014. It now includes a Low Emission Zone (LEZ) for non-road mobile machinery, which was introduced in 2015. The LEZ requires construction machinery between 37 kW and 560 kW to meet at least Euro IIIA regulation when working in Greater London and IIIB when working in central London or Canary Wharf. From 2020, regulations require Euro IIIB emissions standards when working in Greater London and Euro IV when working in central London or Canary Wharf. But there is no obligation to use particulate filters in addition to IIIA and IIIB-standards.

Guideline The Control of Dust and Emissions During Construction and Demolition (Engl.):…

Use of Economic Incentives

The establishment of the Congestion Charging Zone (CCZ) decreased PM10 emissions by 16% and NOx emissions by 13% between 2002 and 2003. The results showed that there was little change in pollutant levels in London as a whole, but there were more substantial falls in the charging zone. In particular the levels of NO2 decreased.

Driving in the CCZ is free for electric cars and for smaller Euro 5 petrol and diesel vehicles, all others have to pay a daily, weekly, monthly or yearly charge. In 2014, a 15% charge increase and a 10% penalty charge increase was imposed. A former 100% congestion charge discount for smaller Euro 5 diesel vehicles was stopped as more and more cars qualified for this.

According to a Mayor’s Announcement, the revenues will be reinvested into London’s transport network and road infrastructure. Unfortunately, the CCZ area was halved in 2011. Charges for the Low and Ultra Low Emission Zones are both additional.

Traffic & Mobility Management Incl. Modal Split

The modal split in London has a high share of public transport, at 36% in 2012. The steady increase of public transport use is accompanied by a steady reduction of private car use. This private motorised transport has a modal share of 37%, which is a decrease of 6% since 2007. Cycling and walking rates remained relatively static for years. The shares of both cycling and walking are predicted to increase slowly between 2012 and 2031, from 2% to 5% for cycling and 24% to 25% for walking.

The city has several programs to support car sharing operators with hybrid and electric cars as well as smarter travel initiatives that promote clean and sustainable ways for travel to work and school. There was also a short-term anti-engine-idling campaign in 2012.

Promotion of Public Transport

The public transport system has been continuously improved and maintained, with good information provision and good accessibility. It consists of a large metro system, trams and 700 bus lines. Besides other local trains, London is currently building a new East-West railway called Crossrail at a cost of £15 billion. This is expected to open in 2018 and will increase London’s rail-based transport network capacity by 10%. Overall, London is investing around £20 billion over ten years in upgrading the metro and train network.

Promotion of Walking & Cycling

Cycling and walking have been relatively static for years, stuck at a modal share of 2% or 24%, respectively. However, actions as well as investments in infrastructure are being undertaken to promote cycling and walking. For instance, 135 km of proper cycle network, including cycle superhighways, already exist. Since 2010, a large bicycle hire scheme with over 11,000 bikes on over 100 km² was put in place, and is one of the largest such schemes in Europe, though expensive to establish and operate. In the context of the Better Streets programme from 2009 the city invested over £450 million between 2010 and 2013 in roads, cycle track and footpath infrastructure as well as public spaces to make streets both more beautiful and better regarding functionality. Further, signage for major walking and cycling routes was installed.

Transparency & Communication Policy

The city’s relatively new web portal provides information about air quality for measuring stations across London with interactive maps. An additional airTEXT website provides the local forecast of daily air quality. Studies show, however, that it wasn’t a great success as only 2% of schools actually were aware of it. Furthermore, Mayor Boris Johnson has refused for years to issue smog warnings.

The best information on air quality is provided by an independent air quality monitoring and information website by the London Air Quality Network. It includes comprehensive background information and interactive maps on air quality, annual air quality reports, data download and direct contact to King’s College. Websites by independent agencies were not taken into account for grading.

Websites on air quality by the Greater London Authority:

Website by the London Air Quality Network (Engl.):

Response to Questionnaire

The City replied to the questionnaire.