ELEMENTAL SA led by prominent Chilean architect Alejandro Aravena was presented with a Global Holcim Awards Finalist 2012 certificate for the Sustainable post-tsunami reconstruction master plan, of Constitución.
The master plan was developed after the 2010 earthquake and tsunami that struck Constitución, a city of 46,000 people located on the shore of the Pacific Ocean and 300km southwest of Chile’s capital, Santiago. 8.8 Earthquake Chile – Sustainable reconstruction master plan proposes a public-private strategy to respond with “geographical answers” to the “geographical threats” of the earthquake and tsunami risk.
Instead of considering a construction ban or a massive barrier along the risk zones, the project proposes to plant the flood-prone areas in order to break the waves. Located behind this first line of defense are facilities that have specific restrictions on the use and layout of ground floor areas. These two interventions are accompanied by an evacuation plan as the third protection element. The aim is a long-term preservation of the city at its historical position next to the estuary mouth – a strategic location for the city’s economy. The complimentary concept is to create public open spaces along the banks of the river that alleviate the lack of inner-city recreation areas as well as support the dissipation of rainwater runoff in order to avoid further flooding.
Half a good house is better than one small one
“Participatory design is not trying to ask people to validate the right answer – but starts by understanding what is the right question,” says Alejandro Aravena.
Supplemented by empirical evidence from the most recent tsunami, the architects relied on mathematical models and laboratory trials. Implementing their master plan proved very challenging both politically and socially, because it required the city to expropriate private land along the riverbank. Elemental’s successful approach was to rely on participatory design to define the citizens’ needs and engage them in the planning process. Today, four years after the earthquake, the individual projects from the master plan are being implemented.
In Constitución, the population has managed to apply the necessary innovation to ensure its protection against future flooding. By adopting a bottom-up approach, in a very constructive way a joint decision has been reached regarding what the city should look like in the future. This exemplary concept is not restricted to Constitución, but could also apply in many geographies around the world that have been destroyed by natural disasters.
Elemental proposed combining the funds available for temporary emergency shelters and social housing to provide better-quality shelters with a higher initial cost that could then be dismantled and reused in an incremental social-housing scheme. The architects designed the social housing units as half of a good house instead of a complete, but small one: building-in the possibility for residents to double the floor area of the house to 80 square meters. Next to each built section of the row house is an open space of the same size into which residents can expand their house. Higher quality social housing eventually increases in value and provides families with capital growth where the collateral can be used to guarantee a loan for a small business, or pay for higher education for children.
Innovation in the built environment in this project did not come from new materials, new techniques or new systems: it came from having the courage to follow common sense ideas, to understand the needs of the people of Constitución, and by viewing the problem in terms of both the micro- and macro-environments.