What will the Grande Dixence region look like 200 years from now?

Master’s project - An EPFL architecture student explored what the area around the Grande Dixence dam in Valais Canton might look like in 2223, drawing on scientific data to shed light on the long-term implications of environmental change.

For her Master’s project, Sarah Planchamp - who recently graduated from EPFL - mapped out a possible future for the area around the Grande Dixence dam, a site that’s close to the heart of the people of Valais Canton. She drew on alternative and emerging practices, such as collective thinking and participatory workshops organized by citizens and academic institutions, to imagine what life might be like 100 years from now and beyond. "IPCC reports aren’t always easy to follow, and their predictions don’t look past 2100," says Planchamp, who is from Valais. "Some of the infrastructure we have today will still exist beyond that date. I wanted to look further into the future - to broaden our thinking by drawing on both current scientific data and the power of imagination. There’s a common saying among local people that if the dam breaks, we’ll all be under water. That’s why I decided to focus on the dam and the surrounding area, which is interesting for many reasons."

During her time at EPFL’s School of Architecture, Civil and Environmental Engineering (ENAC), which actively encourages students to develop interdisciplinary skills and knowledge, Planchamp took classes outside her section, in environmental science and civil engineering. This insight into fields beyond the confines of architecture allowed her to consider the implications of environmental and social change holistically, exploring these long-term phenomena in depth and from new and interesting angles.

Our imagination is an incredibly powerful tool. It’s how we build a common narrative, test hypotheses and tease meaning out of things we don’t understand.

Sarah Planchamp, EPFL architecture student

Government predictions

Planchamp drew on a range of resources in order to build a credible picture of how the Grande Dixence region could change over the next 200 years. Yet she took the power of human imagination as her starting point. "Our imagination is an incredibly powerful tool," she says. "It’s how we build a common narrative, test hypotheses and tease meaning out of things we don’t understand." Planchamp also delved into scientific data produced by the Swiss federal government - these included observed and predicted values regarding temperature, precipitation and vegetation cover for the dam’s entire catchment, an area of more than 420 square kilometers between Sion and Zermatt that includes 35 glaciers. Next, she interviewed scientists working at various ENAC labs to get a sense of how energy demand, soil biology, water flow patterns and the condition of engineering structures might look two centuries from now. She also spoke to members of Polyphème, a collective of authors who count science fiction among their interests. Their fascinating insights helped Planchamp piece together the future world and write an ethnographic study of its new society.

Based on these data and inputs, Planchamp mapped out a possible future for the area in 2223. Under her scenario, precipitation would be less regular, the climate would be hotter and the tree line would have receded to around 1,000 meters above sea level. Society woud be structured differently in order to cope with these new conditions: the population would be the same as today, but the much higher temperatures would render the Rhone valley inhospitable in summer, leading to the revival of migratory herding. With the glaciers having melted and rainfall becoming much less dependable, lakes and other bodies of water would be a lifeline for both energy supply and high-altitude agroforestry systems.

My scenario isn’t necessarily the most likely future. Nor is it a goal to aim for.

Sarah Planchamp, EPFL architecture student

Underground gondola lifts

Although the dam itself would withstand the test of time, much would change - including the water level inside the tunnels. These are currently full to the top between April and November each year. Under Planchamp’s scenario, the water level would be much lower, allowing local residents to cross the mountain through a new system of underground gondola lifts. Crops would be grown on terraces, which would help retain water-borne sediment, thereby keeping the lakes from silting up while creating the fertile soil needed for agroforestry. Farmers would plant crops that are better able to tolerate the new climate, such as those currently grown in the Andes. The terraces would be strategically located to avoid landslides and the threat of more frequent avalanches. Local residents would live underground, in homes built directly into the terraces. And, as Planchamp explains, there would be a stronger sense of community than at present: "People would learn to live with the conditions imposed on them by their environment. They would look out for each other and take care of the natural world around them."

"My scenario isn’t necessarily the most likely future," concludes Planchamp. "Nor is it a goal to aim for. But it’s interesting - and reassuring - to think that low-tech options such as these could make society more resilient. My possible future sets out some ideas we can all get behind as we prepare for what the real future might have in store. This holistic vision of one small community could inspire broader thinking about alternatives to our current way of life."


"One possible future for Grande Dixence", Sarah Planchamp, supervised by Corentin Fivet, Sarah Nichols and André Ullal, 2023.