Air pollution in the city

Vistes de Barcelona sota els núvols de contaminació. © Imatges Barcelona / Paola de Grenet

Jordi Garriga Mas, text Carles Javierre Kohan, infographics

In big cities, the emission of polluting gases has become a serious problem that calls for swift and decisive action. Not only is it detrimental to the health of city residents, but it also contributes to global warming. For this reason, fighting against climate change and improving air quality have become the backbone of their governments’ action. And it’s a fight against the clock.

In Barcelona, one of the foremost measures has been the application of the low-emission zone (LEZ). However, the major challenge is to bring about change in the mobility model, which must be enhanced by expanding the network of bike lanes, improving public transport, increasing the number of recharging points for electric vehicles and boosting the number of trees and green spaces.


Poor air quality

Every year, Barcelona records more than 1,000 premature deaths, more than 2,000 cases of serious illness and more than 1,000 cases of childhood asthma caused or exacerbated by pollution, according to the Air Quality Report (2019) issued by the Barcelona Public Health Agency. Barcelona’s annual average NO2 in the air was 39 μg/m3, just below the legal limit of 40 μg/m3. Nitrogen dioxide (NO2) affects the lungs, inhibits some lung function, causes bronchial irritation, and reduces resistance to respiratory infections. It affects children, especially those with chronic respiratory illnesses, such as asthma or COPD.

Average Annual PM2.5

The city’s mean annual concentration of PM2.5 particulate matter in the air was 17 μg/m3, well above the recommended value of 10 μg/m3 stipulated by the World Health Organization (WHO).

PM2.5 particles accumulate in the respiratory system and are associated with several adverse effects on health, with serious effects on the respiratory and cardiovascular systems.

CO2 Emissions

Carbon dioxide (CO2) is the primary greenhouse gas emitted through human activities. Specifically, it accounts for 81.6% of all such emissions in the European Union (EU). The LEZ aims to halve all these emissions by reducing traffic and banning the circulation of the most polluting vehicles.

Public space occupancy

Private vehicles account for 31% of all journeys made in Barcelona and occupy between 60 and 70% of the city’s public space, including traffic lanes and surface car parks. Excessive use of private vehicles worsens city residents’ quality of life, especially in neighbourhoods with more traffic.

Between 2012 and 2016, the space allocated to pedestrians has risen from 75.3 to 107.4 hectares, although it is still less than the space earmarked for vehicles.

Most polluted roads

The values of most air pollutants are related to traffic in the city. The daily flow of vehicles passing through the Eixample neighbourhood can reach 350,000; on the Ronda de Dalt ring road, 157,000; on the Ronda del Litoral ring road, 84,000; and on the Ronda del Mig ring road, 45,000.

Towards 100% electric mobility

Barcelona plays host to 15% of the electric vehicles registered in the whole of Spain. In the coming years, the increase in electric transport, both private and public, will help reduce pollution and improve air quality. By 2030, the City Council expects all public transport to be electric or hybrid. The Endolla network for recharging private vehicles will have 703 points up and running by the end of 2022 and aims to reach 1,000 points by the end of 2023.

More bike lanes

The increase in Barcelona’s number of bike lanes has encouraged many citizens to use this means of transport, hence helping to reduce the levels of emissions of polluting gases. The Bicing service has extended both its city coverage and the number of bicycles, which has allowed many people to adhere to sustainable mobility. Compared to pre-pandemic figures, the use of bike lanes has increased by 22.4%. By 2023, the city’s bike lane network will be 272.6 kilometres in length.

Urban vegetation to improve air quality

Urban trees can improve environmental conditions and combat pollution. Leaves act as a filter capable of removing air pollutants, thus helping to purify the city’s air. According to the study performed by the Centre for Research on Ecology and Forestry Applications entitled Serveis Ecològics del Verd Urbà [Ecological Services of Barcelona’s Urban Green Areas] (CREAF, 2009), Barcelona’s trees and shrubs removed more than 305 tons of polluting compounds in 2008: 166 tons of PM10 particles, 72.6 tons of O3, 54.6 tons of NO2, 6.8 tons of SO2 and 5.6 tons of CO2.

Stagnation in waste collection

Only 37.7% of all waste generated in Barcelona today is collected selectively (paper and cardboard, glass, plastic and organic waste bins). The municipal target, in line with EU recommendations, is to achieve 55% selective collection by 2025. From 2013 to 2019, the volume of tons of municipal waste grew steadily. In contrast, in 2020, the total amount of waste collected dropped. This decrease is owing to reduced activity in the restaurant and commerce industry during the Covid-19 lockdown.

Fall in waste production

Waste generation has dropped from 1.44 kg per inhabitant per day in 2019 to 1.20 kg in 2021. In this regard, it is especially important to reduce the volume of rubbish disposed of in non-recyclable waste bins, which fell from 490,668 in 2019 to 438,024 tons in 2021.

Reduction in household water consumption

Water-saving and public awareness-raising measures have led to a 28% reduction in water consumption in recent years.

From the issue

Barcelona Metròpolis 123 - Les bretxes digitals

N123 - Jul 22 Index

The newsletter

Subscribe to our newsletter to keep up to date with Barcelona Metròpolis' new developments