From wasteland to opportunity

With the number of urbanites, city dwellers, on the rise, cities are under pressure to accommodate more and more residents and satisfy their needs and demands – ideally without spilling over the already built perimeter. For urban sprawl, the spreading of urban activities onto previously uninhabited land, goes against the precepts of sustainable development. Loosely connected built areas squander space and spoil the landscape. Studies have shown that they lead to higher energy consumption per capita, increased reliance on cars, and much higher infrastructure costs than dense settlements. And urban sprawl has been associated with increasing social disparity.

Over the past decade architects and urban developers seeking to sustainably develop their cities have given urban wastelands – large plots of land left abandoned following the shutting down of factories, railway lines, military sites, hospitals, or other infrastructures – a second life, as contemporary residential, commercial, institutional and public areas. The facts that they tend to be located within urban areas, that they are already tied into the transportation and public utilities networks, and that they are lying idle make them ideal candidates for this type of transformation.

In Switzerland, urban wastelands cover a surface larger than the city of Geneva, and have the potential to absorb the population growth expected for the coming decade. But transforming them sustainably is challenging. According to Professor Emmanuel Rey, from the Laboratory of Architecture and Sustainable Technologies (LAST), it isn’t enough to increase density to a certain value, recycle an optimal fraction of wastewater and locally produce solar energy. “It is essential that we optimize the economic and environmental performance of cities. But to achieve true sustainability, this must be done keeping in mind the social and emotional dimensions as well,” he says.

What makes a neighborhood truly sustainable? Rey says that it must satisfy a wide range of criteria: optimal coordination between urbanization and mobility, high quality sustainable buildings, accessible and attractive public spaces, local services, and a level of social and functional mixing. The result should be a neighborhood that provides a high quality of living to its residents in the heart of the city.

As the vast expanses of urban wastelands suggest, the transformation from a fallow to functioning eco-neighborhood is rarely spontaneous. According to Rey, three key elements are essential for success. First, it takes a trigger to start the process: a new vision for the site, an objective imposed by the urban planning authorities, or a private initiative. Then, the site has to morph into its new role in the minds of those involved – architects, engineers, project developers, pushing them to go beyond “building as usual” and envision bold solutions to the problems they run into. And once under construction, it has to be subject to a regular monitoring process, to ensure that it is being developed sustainably. “Once regenerated, the result can serve as a trigger for transformations on neighboring areas, as you can see right on our doorsteps in Malley, on the outskirts of Lausanne, where a new train station has triggered a wave of urban development on disused sites” says Rey.

But monitoring the sustainability of a neighborhood is a tricky business. Not everything can be captured in numbers, and qualitative criteria can lack objectivity. Rey developed a system of operational indicators that helps combine the best of both worlds, which he applied to the sustainable regeneration of the site on which the Ecoparc neighborhood in Neuchâtel now stands. Besides assisting urban developers and architects in the decision making process, the tool also offers a shared vocabulary, making it much easier to communicate on these issues. “In the near future,” he says, “we plan on continuing the development of this system and on testing it beyond Swiss borders to evaluate its performance in different climates and regulatory environments.”

One thing is clear. There is no single best way to build sustainable neighborhoods. The set of challenges varies with location and time, as does the optimal solution, and what worked in the past may be completely inadequate for the future. A case in point: according to projections made by the Swiss Federal Office of Statistics, by 2030, only roughly a quarter of all households will be home to more than two people. Existing houses and apartments were built for families with a mother, a father, two children and a dog. If the various actors involved in urban and architectural projects don’t anticipate these kinds of structural changes, they will design houses that will not correspond to the societal needs in the future.