Multidisciplinary Project in Porto Alegre, Brazil
Working towards a water-resilient city.
How can you make a city more resilient to flooding without compromising its quality of life? With this question in mind, six students from Delft University of Technology spent ten weeks working in Porto Alegre, Brazil. It was a multidisciplinary project bringing together hydraulic engineering, infrastructure and urban planning.
A city scarred by flooding
In May 2024, the Brazilian city of Porto Alegre was hit by one of the worst floods in its history. Large parts of the city were submerged, thousands of residents were forced to leave their homes, and key infrastructure failed. The floods highlighted just how vulnerable the city is to extreme water levels and how severe the consequences can be when flood defence systems fail. Porto Alegre lies on the Guaíba, a large water system into which several rivers flow. During periods of extreme river discharge, the water cannot be drained away quickly enough, causing water levels to rise sharply. At the same time, urbanisation, limited capacity for rainwater retention and the location of vulnerable neighbourhoods present additional challenges. This prompted us to investigate how Porto Alegre can manage water more effectively in the future.
Six students studying four different subjects
For our Multidisciplinary Project, six of us Master’s students from Delft University of Technology travelled to Brazil. Our team consisted of students from Hydraulic Engineering, Hydraulic and Offshore Structures, Urbanism and Landscape Architecture. For ten weeks, we worked alongside researchers and students from the Universidade Federal do Rio Grande do Sul (UFRGS). We began by exploring the city, speaking to local experts and studying the water system. It soon became clear that the challenges went far beyond simply preventing flooding. For example, in various places, the existing flood defences also form a physical barrier between the city and the water. Furthermore, the consequences of flooding are not evenly distributed: it is precisely the most vulnerable neighbourhoods that are often hardest hit. The question therefore became not only how we could better protect the city, but also how we could, at the same time, make it greener, more accessible and more liveable. This called for a different way of collaborating than we were used to from our own studies. Whilst the engineers focused primarily on technical feasibility and calculations, the urban planning and landscape architecture students challenged us to question existing situations and look beyond the city’s current layout.
From hydraulic models to a new urban layout
Drawing on our expertise across various disciplines, we explored possible solutions, which we ultimately brought together into a single integrated plan. A key part of our research involved modelling the water system around Porto Alegre. Using the SisBaHiA hydrodynamic model, we investigated whether deepening a shallow section of the Guaíba River could improve water discharge during extreme floods. Our simulations showed that this intervention could reduce the maximum water level at Porto Alegre by approximately 15 centimetres. In addition, we investigated how the port could continue to function more effectively during high water levels. To this end, we designed floating pontoons that can move with the water and provide space for port activities and storage. We also developed solutions at the urban level. For example, we investigated how parks and squares could temporarily store rainwater to relieve the burden on the sewerage and pumping systems. For one catchment area studied, a simplified model showed that with just 3 per cent extra water retention, more than twice as many rainfall scenarios could be accommodated. The landscape and urban design proposals focused on reconnecting the city with the water. Examples include a flood-tolerant river park along the Guaíba, green corridors through the city, and the redevelopment of the former port area and the adjacent Fourth District. Ultimately, we combined these various measures into a spatial masterplan and a phased strategy for the future. More than just a technical project What made this project special for us was that we not only learnt about hydraulic engineering challenges, but also about collaborating with other disciplines and within a different culture. During our stay, we were welcomed with great hospitality by the researchers and students at UFRGS. We had the opportunity to combine local knowledge with our own technical background and learnt how important it is to fully understand the people and the environment for which you are designing. The collaboration within our own group was also instructive. We discovered that a technically sound solution is not automatically the best solution for a city. By looking at the same problems from different perspectives, ideas emerged that we probably would not have developed within a single discipline.
Looking back on ten weeks in Brazil
After ten intensive weeks, we can look back on an enlightening and unique experience. Not only have we applied our technical knowledge to a current societal challenge, but we have also learnt how important it is to look beyond the boundaries of our own field of expertise. Our project demonstrates that flood risk management and urban development need not be at odds with one another. Indeed, by combining hydraulic measures with adjustments to infrastructure, nature and public spaces, opportunities arise for a city that is not only more resilient to flooding but also a more pleasant place to live. Thanks to a grant from the KIVI Study and Travel Fund, we were able to carry out this project in Brazil. We are grateful to KIVI for its support and for giving us the opportunity to gain this valuable international experience.
