By their organisation and the multiplicity of their functions, towns and cities can be considered as being complex systems. They are territories that are particularly vulnerable in the face of flooding. Damage to them may weaken the way the territory globally operates and put a country’s economy into peril. Therefore, improving their resilience would appear to be primordial. A resilient town is a town capable of guaranteeing its continuity and adapting itself to changes in the surrounding environment. To do this, it relies on a self-organisation capacity, that is to say a capacity to permanently adjust its behaviour depending on interactions both inside it and with the external environment (Pumain et al., 1989). Urban technical networks occupy a basic position in this capacity (Campanella, 2006, Sanders, 1992, Pelling, 2003). They play the essential role as a support for spreading information, materials, and decisions that enable the territory to operate and make its resilience possible. Therefore, they have to be resilient for the town to be able to survive and live on.