The 1983 Spanish floods were a natural disaster that occurred between 26 and 27 August 1983 in northern Spain, particularly in the Biscay region, where the Aste Nagusia – the Bilbao city festival – had been taking place.
[1] The flood led to preventive measures being put in place and the redevelopment of Bilbao's riverside.
[1] Further heavy rainfall early on the 26th at the confluence of the Nervión and Ibaizabal rivers led to extreme flooding in the city of Bilbao.
[2] This caused significant destruction to Bilbao's Casco Viejo district, seriously damaging some historic buildings, with water 3 metres (9.8 ft) deep in some places.
[2] Following the tragedy, the Basque regional government devised a flood prevention plan, and spent the 2024 equivalent of hundreds of millions of euros on measures to prevent and mitigate the risks,[1] including the installation of early-warning alerts and the provision of drainage systems.