Green corridor
Green corridors, how to take care of the environment in cities?
Cities are increasingly embracing sustainability and, in this process, urban green corridors have an important role to play. These are areas with a significant presence of vegetation that connect key natural areas within a city. They offer numerous benefits to the areas where they are established and are becoming increasingly common in central and residential areas.
According to the United Nations, more than half of the world’s population currently lives in cities and, by 2050, it is estimated that nearly 70% of the population will live in urban areas. This growth makes it necessary to promote nature-based solutions that can improve quality of life and increase the resilience of cities to climate change.
Given such evidence, making cities increasingly more efficient, but also more liveable and sustainable, is key for the planet. It is no coincidence that the development sustainable cities is one of the Sustainable Development Goals promoted by the UN, specifically SDG 11. In this context, green corridors — also called ecological corridors —, along with other sustainable infrastructure, have much to contribute.
What is a green corridor and what is it for
Green corridors are linear landscape features, whether planned or not, that can serve multiple ecological, social and cultural purposes, as well as any other uses compatible with sustainable land use. This definition was coined by Jack Ahern, one of the pioneers of the international green corridor movement.
Ahern’s work explores the possibility of transforming natural landscape features, such as waterways and disused railway lines, into corridors through restoration or construction projects.
Whatever the starting point, the aim of a green corridor is always to connect important natural areas within a city through a strip or passageway characterised by abundant vegetation. In this way, it creates a kind of framework for making cities greener and healthier. Green corridors can incorporate recreational areas, cultural spaces, sports facilities and urban allotments.
How they differ from similar urban concepts:
- Green corridor: connects natural spaces and supports ecological and social functions.
- Linear park: an elongated recreational space, usually associated with roads, rivers or repurposed infrastructure.
- Green belt: a natural or semi-natural area surrounding a city to limit urban expansion and protect the environment.
Green corridors and climate change adaptation
Green corridors are much more than landscaped spaces within cities: they are a form of urban green infrastructure that can help cities adapt to climate change. Connecting parks, rivers, urban forests and other natural spaces creates ecological networks that can help reduce some of the impacts associated with rising temperatures and extreme weather events. The IPCC’s Sixth Assessment Report (AR6)
Enlace externo, se abre en ventana nueva. highlights the importance of urban green infrastructure in increasing cities’ climate resilience by reducing exposure to heatwaves, improving air quality and strengthening their capacity to adapt to extreme events.
During periods of extreme heat, vegetation in these corridors helps lower urban temperatures by providing shade and through evapotranspiration, reducing the urban heat island effect. Permeable soils and vegetation also help absorb rainwater, improving the management of heavy rainfall, while green spaces help improve air quality and create climate shelters where people can protect themselves from high temperatures. In this context, promoting nature-based solutions is part of the global response to climate change. Iberdrola contributes to this effort through its commitment to climate action and biodiversity protection, promoting initiatives aimed at advancing towards a more sustainable model in harmony with nature.
Benefits of green corridors
When it comes to environmental benefits, the most important include:
-
Supporting biodiversity
By increasing the number of green spaces, they enhance biodiversity in urban environments.
-
Promote sustainable mobility
They encourage low-emission forms of transport, such as bicycles and scooters.
-
Improve the urban environment
They reduce air and noise pollution in cities.
-
Reduce urban temperatures
They help prevent the formation of urban heat islands, effectively lowering temperatures.
-
Optimise water management
They contribute to better management of rainwater and stormwater.
-
Strengthen social cohesion
They foster social cohesion by creating accessible public spaces for people to meet and spend time together.
One of the most significant aspects of green corridors is that, in addition to the environmental benefits mentioned above, they also generate social, cultural and economic benefits. For example, they improve people’s quality of life by encouraging physical activity and mental relaxation, support the cultural scene by providing open-air auditoriums and exhibition spaces, and in many cases attract tourists, generating positive economic benefits for cities.
Examples of green corridors
Below, we travel the world to visit some of the most innovative green corridors:
Manhattan Waterfront Greenway (New York)
This 51.4-kilometre corridor runs around the island of Manhattan. Featuring flowers, trees, shrubs, walking paths and cycle lanes, it has significantly improved the quality of life of New Yorkers, according to the city’s one-time mayor, Bill de Blasio. It currently consists of three distinct sections: the Hudson River, East River and Harlem River.
Cuernavaca Railway Linear Park (Mexico City)
This corridor combines practical and aesthetic features along 4.5 kilometres of a historic disused railway line. Covering more than 17,000 m², it helps strike the essential balance between economic and social development, as well as between heritage preservation and transformative potential, according to city authorities. It also contributes to promoting sustainability.
Madrid Río (Madrid)
This huge corridor was created after the M-30 ring road was moved underground along the stretch bordering the Manzanares River. It extends for several kilometres, from El Pardo to Getafe, and by the time construction was completed in 2011, 33,623 trees had been planted. It also helped bring a green lung, the Casa de Campo park, closer to the city centre and improve biodiversity in the area.
Cheonggyecheon (Seoul)
An elevated motorway running alongside a waterway in one of the most central areas of the South Korean capital was demolished because of the enormous amount of emissions and noise it generated. In its place, a huge linear park covering more than 400 hectares was created, which, among other benefits, reduced the area’s average temperature by 3.6°C.