The inspiring transforming of Medellín: from murder capital to sustainable leader

Sustainable Leaders | South America

By Julia Riopelle, Co-Editor in Chief

Published July 13th, 2021

Medellín, Colombia’s second most populous city, is considered a leading example in terms of its environmental policies and sustainable initiatives. Whilst there are other green cities around the globe, the transformation of Medellín is truly remarkable; considering just a few years ago it was a stronghold for Pablo Escobar’s drug crimes and deemed the ‘murder capital of the world’.

In the last decade, Medellín has won various awards and recognitions, including the being a finalist of the Wall Street Journal’s ‘City of the Year Award’; winning the ‘Lee Kuan Yew World City Prize’ issued by the Singapore Government; the ‘Ashden Cooling by Nature Award’ for the city’s innovative Green Corridor Project; and the ‘2020 Smart City Award’ for all of Medellín’s social, urban and cultural transformations.

Medellín, Antioquia, Colombia. | Daniel Vargas / Unsplash

How did Medellín undergo such a drastic transformation and change its public image worldwide? Medellín is situated in Aburrá Valley and is surrounded by mountains, so all the air pollution emitted from the six million people living there is unable to disperse.

In 2013, The Atmospheric Emissions Inventory of the Aburrá Valley found that 70% to 80% of greenhouse gas emissions (GHG) came from motor vehicles; thus, many policies are targeting reducing cars, whilst introducing public transportation, pedestrianization and improving ecomobility.

Medellín aims to cut its carbon emissions by 20% by 2030 and hopes to be carbon neutral by 2050. To achieve this goal, the city launched many ‘Green Projects’ which targeted public transportation, the creation of urban greenspaces and sustainable food productions.

Public Transport Initiatives

The city’s main transformation of the public transport sector was overseen by former mayor Sergio Fajardo (2003 to 2007), who was later named the ‘Best Major of Colombia’ due to his innovative work and policies in Medellín.

In 2005, former mayor Fajardo launched the ‘Pico y Placa’ (the speed and plate) initiative. This aimed to reduce the number of motor vehicles on the road during rush hour traffic, by only allowing half the registered cars to drive during rush hours (7am to 8:30am and 5:30 pm to 7pm) on a particular day. Even and odd license plate numbers alternate each day on who can drive during these hours. Those violating the rules can be fined up to $135 per offence.

In the same year, the Fajardo also began the construction of an integrated and interconnected transportation system, which now links all suburbs and neighbourhoods to its centre. This includes cable cars to communities on the mountain sides, in order to promote social inclusion and offset carbon dioxide emissions.

Cable cars allow more remote mountainside villages to be connected to Medellín city centre. | Marcelo Druck / Flickr

‘Medellín’s transportation systems promotes social inclusion and offsets carbon dioxide emissions.’

The major public transport transformation was overseen by the Área Metropolitana del Valle de Aburrá, a council consisting of ten municipalities in the Aburrá Valley, all of their mayors, representatives from environmental non-profits, a representative from the Colombian Government and more.

Being the largest municipality, the Medellín council provides most of the funding to transform itself and the other municipalities in the region, as well as its mayor being the president of the council. Additional budget for the projects comes mostly from property taxes, donations and a portion of revenues generated from public services.

According to the global network of local governments for sustainability, ICLEI, 506 buses in Medellín were remodeled to use cleaner technology. This decreased pollutant emissions by 4066 tons of carbon dioxide and 5.4 tonnes of particulate matter in the air.

After more than a decade of drastically modernizing their public transport, Medellín is not yet done! Currently, the city is working on doubling its public transport connections, including its MetroPlús bus system which works with low emission technologies, doubling bike lanes in the next three years and adding 50,000 publicly rented EnCicla e-bikes. Medellín is on its way to becoming the capital of electric mobility in South America.

Medellín lines its streets with greenery!

In 2019, former Mayor Federico Gutiérrez (2016 to 2019), launched the Green Corridor project, lining all the streets, sidewalks and waterways of Medellín with strips of diverse plants, trees and vegetative cover. This helped reduce the impact of the ‘heat island effect’, which describes how urbanized areas experience higher temperatures. This is because concrete and other artificial structures absorb and re-emit more heat than natural landscapes.

According to the UNEP: ‘Urban parks can reduce ambient daytime temperature by an average of approximately 1°C. Whilst green roofs can cut energy use by 10 to 15 per cent.’

Urban trees can absorb carbon dioxide from the atmosphere via sequestration. Green spaces with healthy soil can also increase carbon sequestration, biodiversity microhabitats, and storm water regulation due to its absorption capacity.

‘When we made the decision to plant the thirty green corridors, we focused on areas which most lacked green spaces,’ explained former Mayor Gutiérrez. ‘With this intervention we have managed to reduce temperature by more than 2°C.’

Including urban greenspaces is especially vital in a time where more and more heat waves will hit major urban areas. Rather than spending excessive energy on installing air conditioning around the city, cities should start planting thousands to millions of trees throughout. In addition to the Green Corridor Project, the Seeking Future Project aims to plant a further one million trees in the region—to date they have already planted 250,000.

Medellín’s streets are flourishing with greenscapes. | Ivar Erre Jota / Flickr

Where is Medellín heading to next in the future?

Medellín’s next project to increase its green status even further is heading towards quite a large-scale change. Metropolitan Greenbelt Plan is a municipal government approved plan, under current mayor’s Daniel Quintero’s council, aimed to address both urban growth and increase urban greenspaces. The objectives of the Greenbelt Plan are in alignment with the city’s 2030 sustainability targets; improving environmental sustainability, social inclusion, housing improvement, mobility and connectivity of municipalities.

The Metropolitan Greenbelt will stretch 72 kilometres and be split into four ‘bands’, consisting of (1) the Buffer Strip, (2) the Transition Strip, (3) the Mobility Corridor and (4) the Urban Strip. Each band has certain activities which are allowed or prohibited within it.

Outermost band ‘Buffer Strip’, will prioritize rural and environmental protection, and involve projects to do with ecosystem restoration, ecological tourism, sustainable food production, rural housing improvement, removing informal settlements, hiking and biking trails. Additionally, the Buffer Strip will be equipped with regular resting areas, LED lighting and security cameras.

The next band from the outside in is the ‘Transition Strip’, which will have public spaces, such as education facilities, eco-parks, eco-orchards built within them. The transition strip will also be constructed to function as environmental hazard mitigation and watershed recovery.

‘Greenbelt Plan will improve environmental sustainability, social inclusion, housing improvement, and connectivity of municipalities.’

The Mobility Corridor will be the second innermost band of the Metropolitan Greenbelt, with its main purpose being longitudinal connectivity. This section will link new transportation projects to the existing city centre transport connections, as well as provide efficient public transport connection to more remote neighboring towns along the valley’s mountainsides.

Finally, the Urban Strip contains the city’s centre and surrounds the Medellín River which bisects the Valley. It will be the location of housing for those who need to be resettled due to this project, the public and private sector and future urban development projects.

The project, developed between 2012 and 2013 by a team from the National University of Colombia and funded by the Área Metropolitana del Valle de Aburrá, is estimated to take 17 years to complete.

However, the Greenbelt project would need to relocate an estimated 6591 households from the outermost ‘Buffer Strip’ band. The most affected area would be the informal settlement known as ‘Comuna 8’—which is difficult, as this area has a constant incoming stream of new inhabitants.

Comuna 8, Medellín, Colombia | Ellis Calvin / Flickr

Colombia’s long history of violence due to political polarization resulted in a 10-year civil war, which further fragmented the country and its people. Although Medellín has overcome many political and drug-related crimes, these are still prevalent throughout the country. Colombia has between 4.9 to 5.5 internally displaced people, who mostly flocked to urban areas such as Medellín to escape crime and seek protection.

Additionally, 40% of those living in Comuna 8 are internally displaced people, who live in informal, self-built homes. The area is close to Medellín city centre but hard to access, due to its position on the steep mountain slopes. Thus, the community needs to assess and outline who has the priority to stay and who is able to relocate—which again, is a difficult task to execute. To date, there is no deadline put in place for when this decision will be made.

The Metropolitan Greenbelt Plan is putting strategies into place to provide housing for those who need to relocate to the Urban Strip. However, the project also threatens existing community farms, which are units where many people grow their own food, as part of an urban agricultural program known as the ‘EcoGarden Project’ in Medellín.

‘40% of those living in Comuna 8 are internally displaced people.’

The EcoGarden project encourages citizens—particularly youths—to sustainably grow their own food, in order to have less reliance on foreign imports. 441 people between ages 14 to 28 have already received their own free EcoGarden starter kit from the regional government.

A proposed strategy, which would require much government support and funding, proposes the implementation of new farming technologies in both the Buffer Strip and the Urban Strip, in order to provide incentive to people to live in multi-family housing units. The introduction of hydroponic farming and rainwater collection are sustainable and attractive solutions, and if successful, would also reduce the space needed for housing. Hydroponics has shown to be a success in providing food security to low-income communities in Uruguay.

Medellín is definitely a city to look to as an innovative, future thinking leader for their green initiatives and environmentally conscious policies. Even wealthier countries around the world can take an example or two from Medellín, for inspiration to make their own cities more sustainable.

Featured Image: Mike Swigunski | Unsplash

Barrows L., Lingjun B., Calvin E., Richardson J., Sollenberger G., Irazábal C., Buchholz N. (N/A) Growth Management in Medellín, Colombia. Universidad Nacional de Colombia, Sede Medellín. Universidad Nacional de Colombia, Sede Bogotá. Universitat International de Catalunya.

Hinge A., Bush S., Jordan W., Kim J., Le Y., Poddar D. and Torreon C. (2017) Policy path to improve urban air quality in Medellín, Colombia. Columbia University: School of International and Public Affairs. La Ciudad Verde.

ICLEI (2017) ‘Medellín, Colombia: social innovation through sustainable urban mobility.’ ICLEI—Local Governments for Sustainability. Available at: [Accessed July 12th 2021]

ITDP (2012) ‘Medellín: A leader in sustainable transport.’ Institute for Transportation & Development Policy. Available at: [Accessed July 12th 2021]

Modak S. (2020) ‘How Medellín plans to become South America’s first eco-city.’ Condé Nast Traveler. Available at: [Accessed July 12th 2021]

UN Environment Programme (2019) ‘Medellín shows how nature-based solutions can keep people and planet cool.’ United Nations. Available at: [Accessed July 12th 2021]

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