1.2 Defining a Physical Resilient City

Physical resilience within a city is typically the one which immediately springs to mind when discussing resilience. The effect of its presence, or lack of, can be seen or felt immediately and has an easily measurable and quantifiable effect. Bilbao in Spain has an excellent example of physical resilience with regards to it’s flood defence systems. The city is currently undertaking extensive works along the river-front. The Nerbioi valley which Bilbao is located has flooding as it’s primary threat. Over the past 600 years, the city has been flooded over 40 times, with the frequency of them occurring nearly two-fold in the last century. (fig.1)

The city is tackling the problem through several interventions, the largest being the Zorrotzaurre redevelopment. The proposal turns the peninsula into an island and creating a canal which is lined with green banks, serving as both social infrastructure and as a physical flood defence. This will increase the buffer capacity by over 1 meter. In the event that a flood did occur, the buildings close to the river have been designed with ‘floodable’ ground floors, using water-proof materials and non-perishing furniture, which can quickly and easily be re-occupied and dried out once the flood water reseeds. RESIN, carried out an independent flood research and found that the city could see a 100% reduction in costs for flood damage over 10 years and a 95% reduction in costs over 100 years where extreme events may cause minor damage, resulting in €162m predicted savings.7 Using this example, we can see that physical resilience is a built intervention which increase the buffer capacity of existing systems while allowing for quick repair/adaptation in extreme circumstances.

Figure 1: Areas prone to flooding in Bilbao (Territorial Plan for Rivers and Streams, Basque Government, 2000)