Sustainable technologies are not only critical to our future, but are making for a better present in the Colombian city of Medellin.
For proof, you don’t have to look any further than the transformation of El Morro de Moravia, a rubbish dump neighbourhood once declared a “public disaster,” into an urban park with an ecomuseum and science-technology centre.
The transformation has also provided a technology testing ground for researchers at the UNESCO Chair of Sustainability at Barcelona’s Universitat Politècnica de Catalunya (UPC). For example, the site has enabled researchers to try out the combination of natural treatment technologies such as constructed wetlands, and buffer strips, which are strips of vegetation that absorb and help degrade pollutants.
During the 1970s and 1980s, the city of Medellin saw a large influx of displaced persons from rural areas who settled spontaneously, with barracks, on a large garbage dump located next to the bus station. The appalling living conditions there prompted Colombia’s Interior Ministry to declare Morro de Moravia a “public disaster” in 2006.
Following that declaration, officials launched a comprehensive intervention project with three stages of action: the relocation of inhabitants, decontamination and recovery of Morro as public space. They also enlisted the help of researchers at UPC.
The first phase of the project, and the most urgent, was to relocate more than 10,000 people living in the dump into new homes built in other areas of the city. As of today, 75 per cent of El Morro’s residents are already living in their new homes in neighbourhoods equipped with all kinds of services.
Whenever a barrack is abandoned, project leaders stick a flag with the colour of the new neighborhood where the family has gone to live. The process was done in a participatory manner, in accordance with community members who are also responsible for seeing that evacuated areas are not re-invaded.
The second phase of the project involves the recovery of El Morro and treatment of the many pollutants that are present. The intervention includes treatment of the leachate — contaminated liquids from litter decomposition — that was generated over the years. For this, Medellín called on the Alpha network on Sustainable Technologies for Drinking and Wastewater Treatment (TECSPAR). Members of this network include the UNESCO Chair of Sustainability at UPC, coordinated by Jordi Morato, director of the same chair and coordinator of the Sustainable Water Management of the UPC (AQUASOST).
Researchers are already working in the Morro to turn it into a park through natural treatment techniques combining buffer strips and wetland construction. The buffer strips are strips of vegetation imitating the fringes bordering the river channels. Their natural structure controls the air, soil and water quality, acts as a filter of nutrients and pesticides, helps to keep the flow of these elements, and thus, reduces their arrival at the same channel.
The constructed wetlands are low-cost systems consisting of shallow channels where water circulates underground through a granular medium in contact with the roots of typical wetlands plants. The water is purified through a combination of physical, chemical and, especially, biological phenomena.
Such strategies not only mimic the working of nature, but are both low cost and low energy with minimal after-care requirements. They also work without generating waste, odours or mosquitoes.
With financing from international agencies, UPC researchers have designed a demonstration plant that will apply these technologies in one zone of the Morro to be converted into a park. In this way, they will help to reduce the transformation time of what once was a huge mountain of trash into a park with biodiversity.
The third phase of the Morro tranformation aims to make it a meeting and leisure space for the area. The park will also feature an ecomuseum and science-technology centre.
Barcelona, where the UPC is located, actually once experienced a recovery process similar to that taking place in the Morro de Moravia. Barcelona’s Botanical Garden, located in the mountain of Montjuic, was in fact once a rubbish dump.