Supporting urban greening and social justice in the city of Barcelona

Barcelona is a densely built city facing an increasing number of urban challenges. Flooding, rising sea-levels and extreme temperatures exacerbated by the urban heat island effect are the most common climate change-related threats in Barcelona. In 2014, an analysis of the urban heat island concluded that Eixample is the hottest district in the city (Ajuntament de Barcelona, 2014). Also, the number of heatwaves is expected to multiply by eight by the end of the century: 50 to 80 days with temperatures above 30 °C by the end of the century are expected, depending on the Representative Concentration Pathway (RCP) – 4.5 or 8.5 used for the projections. The city is also prone to flooding due to heavy rainfall which causes problems for the sewage system. This is mainly expected in the districts of Poblenou and the axis of the Diagonal, Sant Andreu, Sants-Badal and Barrio de Sant Antoni. In the past years, Barcelona has invested in a network of trees as a green infrastructure, which, beyond benefits for climate change adaptation, led to some challenges: health and safety risks due to pollen, risk of falling trees or branches, tree pests or diseases, and limitation of the space availability for other uses. On the other hand, trees are experiencing water and heat stress during the summer dry season that will be likely aggravated in the future due to expected climate change. Intense sunlight and high temperatures cause high rates of evapotranspiration and water loss from leaves. Moreover, urban trees have only a small water reserve because of the prevalence of impermeable ground (e.g. tarmac, pavements), causing drought stress, and vulnerability to plant diseases and premature defoliation.

In addition, Barcelona is struggling with socio-economic challenges, such as environmental injustice related to climate challenges, poor air quality and food insecurity. Environmental injustice refers to unequal access to green spaces and green gentrification. This is due to increases in housing costs, property values, and private capital in areas where greening has been created or improved. As a consequence, residents and small scale businesses with low income can be forced to leave their neighbourhoods. The Barcelona Lab for Urban Environmental Justice and Sustainability (Anguelovski et al., 2017) has analysed the green gentrification trend related to 18 new green spaces/parks. The researchers found that green gentrification in socially vulnerable neighbourhoods is a complex phenomenon that depends on the context as well as the existing built environment. Green gentrification in Barcelona was strongest in most desired areas located near the central area or coast. Conversely, low green gentrification in other areas can be related to the distance from cultural amenities and the city centre. The people most at risk of gentrification in Barcelona are the low as well as middle income households and immigrant populations coming from the Global South.

The city of Barcelona is pursuing an ambitious urban greening strategy. It is also integrated into the city’s climate change strategy, and aims at enhancing (?) access to urban green spaces, to provide multiple benefits: biodiversity protection, clean air, interaction with nature, and support many health, social and leisure activities, further to cooling of outdoor spaces. The most recent plan foresees the increase of urban green space by more than 160 hectares between 2020 and 2030, further to the increase by 58 ha achieved between 2016 and 2019 (Stimulus programme for the city's urban green infrastructure - Ajuntament de barcelona, 2017). The greening initiative aims at creating connectivity to both the urban and natural environment. It also strives to increase biodiversity and accurately select species for enhancing resilience and adapt urban greening to climate change. It alos creates awareness among citizens about the value of urban greening and its benefits. Barcelona wants green areas to be accessible and useful for all its citizens. Being aware that urban greening lead to an increased attractiveness which may result in rising housing prices, the city government tries to actively counteract such tendencies, keeping housing affordable for all. Specific policy measures have been adopted by the City Council to make sure that the development of Barcelona will take place in a socially just way without further enhancing gentrification, including green gentrification.

The solutions for greening in a just way are coming from two city departments: the environment department and the housing department. The environmental department of the city mainly focusses on making green areas accessible and useful for all social groups, while the housing department is introducing measures to deal with gentrification throughout the city.

An inclusive and participatory approach is at the core of the city’s greening strategy, which was initiated with the Green Infrastructure and Biodiversity Plan 2020 (GIBP) in 2013, the Stimulus Programme for promoting Green Infrastructure (Ajuntament de barcelona, 2017), and the “Tree Master Plan” adopted in 2017 with a time horizon until 2037.

Until 2020, the GIBP represented the “umbrella” strategic plan for actions related to green infrastructure and biodiversity in Barcelona. GIBP Barcelona was seeking to enhance the city’s  ecological, environmental, social and economic services by connecting various areas with vegetation to produce effective ecological infrastructure. The aim was to secure a city model where nature and urbanity interact and enhance one another for the benefit of citizens. In this model, citizensderive welfare from the natural heritage and are actively engaged in the protection and improvement of all areas.

Considered the importance of urban trees for the urban climate, the Tree Master plan plays a large role for implementing the city’s greening strategy. According to a tree inventory still under development, the city of Barcelona is responsible for approximately 310,800 individual trees, out of them 65% are located in urban areas (including the trees lining streets and squares), around 12% are in municipal parks and gardens, and around 23% are in woodland areas. The plan is specifically targeted to the maintenance and enhancement of urban tree coverage. With its 10 strategic lines and 46 actions, it covers the management of trees both in public and private areas. A close collaboration between different municipal departments is recommended for the overall management of trees..

In 2021, the city of Barcelona updated this strategy with the ‘Barcelona Nature Plan 2030’ that rolls  the quantitative objectives of the GIBP forward. One key goal is to add an extra 1m² of greenery per resident by 2030, equivalent to 160 hectares of new green spaces, out of them 8.6 hectares have to be realized in the first two years. By 2030, the plan will increase the urban share of Barcelona’s green areas from 2,077ha to 2,237 ha (+160 ha equal to +7.7%). In 2020, with respect to 2016, urban green areas have been incremented by 40 ha, thus achieving the 25% of the 2030 goal.. The Barcelona Nature Plan also envisages to implement 40 projects together with residents as part of the program "All Hands to greenery" (“Mans al verd”) In this way the number of participants in activities on biodiversity protection or climate adaptation should be doubled . Overall, the implementation of the urban greening model follows criteria of fairness, gender perspective, accessibility, size and quantity as well as connectivity at city and metropolitan level. Green areas are designed to meet the diverse societal demands from different social groups.

Moreover, aiming at enhancing climate resilience in a well distributed way across all neighbourhoods, the city of Barcelona is creating a network of Climate shelters, places where people cool down during hot weather. The initiative started in 2019 within the collaborative project Climate Shelters (2019-2020) funded by the Urban Innovation Actions (UIA) programme of the European Commission. This project has converted the 11 selected schools into climate shelters open to all city residents during hot periods. The children were involved in the design and evaluation of the climate solutions. Blue, green and grey interventions are implemented to deal with heat.  As a result, 1,000 square metres of natural space was regained, with vegetation in playgrounds and the creation of 2,213 square meters of new shade using pergolas and awnings. In addition, 74 trees were planted and 26 new water sources were installed. Meanwhile, a total of 197 shelters are available, also including libraries, municipal sports centres, parks and gardens, and museums. These shelters are distributed in a way that 95% of the population can reach a shelter in 10 minutes walk.

Greening finally takes place as part of the Barcelona Superblock plan which aims to enhance sustainability of the city together with citizens. The Superblocks are a way to combine mitigation and adaptation. The idea is to put everyday life at the core of district development, connect neighbourhoods and promote an inclusive transformation towards sustainable mobility and green and low emissions areas. Creating liveable public spaces, neighbourhoods become greener, with more space for sustainable mobility. New shops, restaurants and local commercial also emerge. In order to avoid gentrification as a consequence of increased attractiveness, 6,100 public dwellings have either been built or are in the pipeline since 2016, along with the acquisition of nearly 1,000 flats to protect neighbourhood life and preserve an affordable housing stock. Ongoing and completed works from the Barcelona Superblock plan can be found on an interactive map. Once these projects are completed, a million square metres of asphalt will have been given over for use by local people and 40 hectares of new greenery will be added.

This superblock concept is now upscaled to the whole of Barcelona via the Superilla Barcelona project. Superilla project refers to the development of multiple superblocks in different districts in Barcelona. The goal is to allow citizens reaching attractive oudoor spaces spaces in a distance of 200m. Inclusion of people and their wellbeing is at the core, to make sure the future of the city is fairer, healthier, more inclusive and a diverse place to live.

Alongside with these initiatives, the housing department of the city is introducing measures to deal with gentrification throughout the city which is driven by increasing tourism and environmental attractiveness. Barcelona signed the and the Mayor is taking a lead at EU level to bring cities together to develop an approach to fight gentrification: 

• to make it less lucrative to buy property,
• to control and lower rental prices and prevent unfair rent increases, to make dwellings in central urban areas affordable and prevent social exclusion.

Specifically, the city of Barcelona has introduced the mechanism to allocate 30% of new housing or renovations to social housing, meaning that between 300 and 400 affordable homes each year are built. Furthermore, the city has the possibility to adjust property taxes for low income households in areas where prices are increasing, preventing gentrification. This is especially important for areas that have increased the property value due to greening interventions.

Stakeholder participation is an essential element to make sure greening is taking place in a socially just way. Therefore, all greening programmes encourage stakeholders’ participation from different social groups, including the most vulnerable. Strong engagement of stakeholders is widely present and the approach is described on the city’s website dedicated to participation processes.

With regard to the development of the green plans, the Barcelona City Government is relying on the ‘Sustainability Participatory Council’, which consists of elected representatives from the More Sustainable Barcelona (B+S) network which was established in 2002. This is a network including schools, businesses, NGOs and universities who participated in a process to draft a collective action plan and commitment: Barcelona's Commitment to Climate. The ‘Citizen Council for Sustainability’ is engaged in the development of the key sustainability plans in Barcelona.

The Green Infrastructure and Biodiversity Plan 2020 has involved the public to manage urban green areas and to promote new greening activities like creating vegetable gardens and school or community gardens; involvement in municipal vegetable gardens as users or as organisations; planting and maintenance of tree pits; maintenance of green areas (e.g. looking after green walls or school ponds) and installing nest boxes and “insect hotels”. Strategic ways to involve the public were communication and education, participation of businesses, civic and professional associations, trade unions, foundations, universities, schools and various areas and districts of the local administration; and cooperation like the development of technical services by communities.

The Nature Plan 2030, which is the continuation of the GIBP 2020,  is also being developed in a participatory way together with key experts and practitioners. Feedback from the general public was gathered to find agreement on long-term challenges and goals and to collect proposals for biodiversity protection and greening activities to be included in the Nature Plan 2030. In total, 10 sessions with altogether 141 participants were organized between December 2020 and May 2021.

The Climate Shelter project has been oriented to schools and to turning parks, facilities and urban equipment into climate shelters. Primary schools involved in the project organised participatory events that were attended by teachers, students, parents and representatives of the partners to the Climate Shelters project. The events were targeted to: motivate the school community to the project, assess the needs of each school, gather ideas and suggestions for the adaptation of the school and its yard(s) to climate change, facilitate the interaction with scientists and architects and develop ownership of the project by the school community. Schools became highly motivated once participatory co-production processes were applied and space was given for innovation and creativity. Taken that they can act as hubs for the neighbourhood, their role is central for social cohesion as well as for climate awareness. Furthermore, a working group was created within the Citizen Council for Sustainability to work on the concept of climate shelter.

The Barcelona Superblock program is carried out with strong involvement of residents, entities and social groups. Inclusion is at the core of this programme and participation is open to all interested people through meetings and activities, both at the neighbourhood and city level. The participatory processes usually have information sessions and workshops open to residents, city authorities and all interested parties. Furthermore, there is  a steering group in each area formed by representatives of city authorities and the City Council, which acts as permanent promoters.

Greening in Barcelona, especially for the implementation of the Tree Master Plan has been successful so far because of the broad stakeholder participation. It has helped to create networks and has strengthened institutional relations with the organisations involved in the conservation of biodiversity and green infrastructure in the city.

Another success factor are certainly the political leadership and the international collaborations established by the Mayor of Barcelona. The municipality closely collaborates with cities like Paris to develop appropriate policy measures to avoid gentrification and to support affordable housing. Strong support of high-level decisionmakers helps to successfully implement new strategies, plans and tools. The City Council of Barcelona is a member of several sustainability-related city networks such as C40 and Eurocities. As a member of Local Governments for Sustainability (ICLEI), it was a pioneer participant of ICLEI’s Local Action for Biodiversity Programme.

Furthermore, close and long-term collaboration with researchers has brought science-based evidence and  external funding and expertise to implement, pilot and test different adaptation and greening measures. The city of Barcelona is and has been an active collaborator in several EU funded projects such as OpenNESS (2013-2017) Naturvation (2017-2021) or GreenLULUs (2016-2022). Those projects  aim to develop a new method (i.e., an index called the Fair Urban Greening index) in order to assess the racial and social impact of urban greening projects and compare cities’ performance over time and with each other. Also, the Barcelona Laboratory for Urban Environmental Justice and Sustainability plays a major role in providing evidence on gentrification trends as well as potential solutions to deal with these developments. The Barcelona partnership closely collaborates with international partners to explore options and policy measures for green gentrification.

Municipal governance, based on collaboration between the departments of urban planning, environment and housing, along with long-term commitment at all levels, contribute to the success of greening initiatives. However, while staff shortages can be a challenge. Technical and organisational innovation is also a limiting factor as it needs to be understood and accepted by project-related stakeholders and society. In this sense, training needs and social participation are key elements still to be tackled for a swifter implementation of greening measures. Another limitation is that the environmental department working on the greening strategy largely depends on spaces that can become available for greening. If socio-economic criteria need to be assessed, the selection of suitable areas for greening can become more challenging.

Another challenge with this type of measures is that they are highly contested by different interest groups and they can be easily the subject of legal conflict. Furthermore, it is not always clear which government level is responsible for their implementation.

Furthermore, green infrastructure need to be maintened and managed over time, to avoid possible risks of falling trees or branches, tree pests or diseases, defoliation, and water stress.

The Barcelona Trees Master plan has a cost of 9.6 million euros/year. Of this budget, 8.3 million Euros/year is already available for tree management. The difference of 1.3 M €/year relates to necessary investments mainly in the areas of improved soil and water management.

The Barcelona Superblock costs cover collaborative and implementation work in greening of public space. The total estimated is 37.8  M €.

Climate Shelter in schools was a collaborative project (2019-2021) funded by the Barcelona City Council (1 M €) and external funding from the EU funding progamme Urban Innovation Action (UIA) (4M €). The total budget of the project was 5M €. The project partners include Barcelona City Council, the Barcelona Education Consortium, the public service provider Barcelona Cicle de l'Aigua SA (BCASA), the Public Health Agency of Barcelona (ASPB), the UAB Institute for Environmental Science and Technology (ICTA-UAB), Barcelona Institute for Global Health (IS Global) and Vila Olímpica school. The budget is on average 200.000 euro per school.

Gentrification measures, mostly related to regulations changes are not very costly. The most relevant costs included the establishment of subsidy programmes, the expropriation of a small amount of buildings by the City Council and the small loss of public income due to the reduction of property taxes of some households. The reduction of property taxes also renounces on future rises of taxes with rising real estate prices.

As for benefits, new trees planted within the Tree Master plan and new green areas are improving the urban microclimate and tempering the climate conditions of Barcelona by providing cooling. Furthermore, trees and green areas can prevent possible local flooding by helping to reduce the amount of storm water runoff. Trees can also provide a number of co-benefits like cleaning air, storing carbon, reducing noise pollution, balancing water cycle, improving biodiversity. They can make the living environment more attractive. Initiatives undertaken under the Green Infrastructure and Biodiversity Plan 2020 and the Barcelona Nature Plan 2030 are providing Barcelona with extended green areas accessible to all its citizens, including the most vulnerable groups. These initiative can definitely alleviate people from the increasing health impacts of heatwaves due to climate change.

The conservation of biodiversity and the strengthening of green infrastructure have been incorporated into the local political commitments and human and financial resources have been allocated to it. Moreover, urban greening work is carried out in a coordinated manner ensuring goals are aligned with other similar municipal local projects and plans, other institutions and bodies affording knowledge, energy and actions with a view to building a future-proof Barcelona.

The city’s environmental legislation considers all trees part of Barcelona's arboreal heritage, both those in areas of public and of private property. While the City Council is concerned with the management of the municipal property trees, establishing and implementing management and protection guidelines, its overall responsibility is to preserve the broader arboreal heritage in order to improve the environmental quality of the city and enrich biodiversity and accompanying ecosystem services.

Gentrification prevention in Barcelona involved the introduction of changes in the legislation and new regulations to establish for instance the proportion of social housing in renovated districts, the rent index, the adjustments of property taxes, and the allocation of tourism licences.

The Tree Master Plan started in 2017 and has a time horizon of 20 years. Some actions took place quite fast after the launch, other actions are taking more time. Planning to greening Barcelona started in 2013 with the Green Infrastructure and Biodiversity Plan (GIBP). Measures are currently being implemented within a wide range of projects and are expected to achieve the quantitative objectives set in the updated greening strategy by 2030 (Barcelona Nature Plan). The EU financed Climate shelters-Schools project run from  2019-to 2021, and has been upscaled as a municipal policy with the aim to create more climate shelters. Pilots in the Barcelona Superblock program and Superilla started in 2014 and are ongoing.

Although the lifetime of the Trees Masterplan is 20 years and  Barcelona Nature Plan targets 2030, it is expected that the new green areas will continue existing after that date, as well as the municipal management and the conservation policies for urban greening of Barcelona. Conversely, most legal measures related to gentrification may be temporary and may be removed after possible legal conflicts or when another political party is in power.

Barcelona Lab for Urban Environmental Justice and Sustainability
Carrer del Dr. Aiguader, 88
08003 Barcelona, Spain
Email: ana@bcnuej.org

Coloma Rull
Barcelona City Council
Biodiversity Programme
Torrent de l’Olla 218-220, Barcelona
E-mail: crull@bcn.cat


Toni Pujol Vidal
Barcelona City Council
Ecology, Urban Planning & Mobility Strategy Department
Diagonal 240, 4th floor
E-mail: tpujol@bcn.cat

Ajuntament de Barcelona, 2021. Barcelona Nature Plan 2021 - 2030, Ajuntament de Barcelona; Area of Urban Ecology, Barcelona, Spain

BCNUEJ, 2021. Policy and planning tools for urban green justice. Fighting displacement and gentrification and improving accessibility and inclusiveness to green amenities

PLA CLIMA. Resum executu. Effecte illa de calor

Superilla Barcelona. Cap a la ciutat que volem

Anguelovski, I., Connolly, J. J., Masip, L., & Pearsall, H. (2018). Assessing green gentrification in historically disenfranchised neighborhoods: a longitudinal and spatial analysis of Barcelona. Urban Geography, 39(3), 458-491.