Fernanda Garcia Alba Garciadiego, University College London (London, UK): Mexico City’s Blue Pattern
Today the world is more urban than ever, half of the world’s population (3.3 billion people) live in urban areas. This is expected to reach 5 billion by 2030 (United Nations Population Fund, 2007). Most of the urban growth is taking place in the Developing Countries, where many newly urban inhabitants will be living in neglected or informal areas, within a high environment deterioration. As an example, Mexico City sprawl and the constant conflict of this settlement with the water has originated a high distributed environment and an unsustainable city. This poster will describe the actual Mexico City´s problems and the possible solutions to attenuate the degradation of its area, especially in the peri-urban area of this metropolitan area.
Mexico City was originally settled over a network of lakes. Through the time these lakes disappeared in order to provide “resilience” to the city against floods. Finally, the lakes were dried out at the beginning of the Twenty Century, surviving just some aquifers in the city. However, this “flood resilience” is just a false impression. The rains and water patterns follow the original water configuration. In this manner, the water from the city’s outskirts (natural streams, rivers and rain water) tends to follow the natural framework and reaches the lower parts of the city. The run off of these areas, especially from the southwest, are increasing the vulnerability of the whole city.
In addition, Mexico City water infrastructure is reaching its limits. Nowadays, the city is incapable to supply with basic services, like fresh water, to its citizens. To ensure the water supply to Mexico City´s population, it is getting necessary to get and transport water from further and lower places, representing a highly cost to the whole country. However, the construction work would be inefficient because the population is still growing. Mexico City consumes 62 thousand litres of water per second. From the whole amount of domestic water, 70% comes from the underground aquifers while the other 30% comes from external water systems -Cutzamala and Lerma Systems-. However, the underground water is decreasing because the irrational consumption. This water is just been taking out and there is not water filtering into the subsoil to keep balance of the amount of water from the underground.
Mexico City has being denying its water character for a long time, which has created serious problems in the urban settlement. So, would it be possible to use the water patter as a central point of planning design? The answer is still unknown, however there are several approaches that aims an ecological balance and a water cycle restauration. The Water Sustainable Urban Design (WSUD) valuate the water as a main driver in the urban planning, while managing excess water as an asset instead as a hazard. Thus, would it be viable to design ecological sustainability within a WSUD approach? The idea is incorporate this approach in the southwest area of Mexico City, where most of the rainy events and mountain surfaces are concentrated.
This capital city have 804 irregular settlements, must of them are in the southwest conservation area, representing an important reduction of aquifer recharge zones. However, to evict these communities is not a socially sustainable scheme, due most of them has been living in this area for a long time; while dwelling relocation can result in a social and economic repercussion to the city. There are possible odds regarding working with not traditional urban patterns and marginalized societies. Previous experience has shown us that traditional planning approaches tend to fail when dynamic social environments are incorporated into fixed-designed spaces, which most of the time does not fulfill the people necessities. For that reason, it is important to address this problem from other perspective.
The Green Infrastructure(GI) is a multi-functional approach that can pursuit several results in many fields (biodiversity, flood reduction and amenity hubs, among other domains) though green networks. But most important, the Green Infrastructure influences the urban planning in order to create green spaces to improve the social equity and cohesion.
There are many planning approaches to incorporate sustainability into the city, especially in relation with the water-cycle balance inside the urban framework. Most of these approaches have been done in Developed Countries. For that reason, this poster will describe the existing urban problems and the possibilities of incorporate WSUD and GI into a peri-urban-informal area in a city from a Developing Country, such as Mexico City.