Barcelona is a densely urbanized city on the Mediterranean coast in Northern Spain. It has bright cool winters and even brighter hot summers with occasional high intensity rainfall events causing serious flooding.
The main impact of rainfall events is the damage to infrastructure, mainly underground facilities; disruption of communications and traffic, with the associated effects on business and commercial activities; damage to underground public transport; damage to garages, cellar and buildings; and loss of life. Barcelona’s sewer network is a combined system with 1,650 km of sewers, 55% allowing man-entry.
The average age of the city's sewers is 70 years and 33% of the network has mid or grave defects. In 1992, the state of the system was that the Great Olympic sewerage works had finished, there was a functioning network, but it was still insufficient and inflexible and the management was done conventionally. In the intervening years, CLABSA has transformed the system such that Barcelona has one of the most advanced urban flood management systems in the world.