The Government adds 172 more kilometers to the map of flood zones

Floods are the main natural hazard for people in Catalonia: since 1980 there have been 301 floods, resulting in 131 deaths. After two years of analysis and studies to comply with the European directive on flooding, the Catalan Water Agency (ACA) has updated the map of rivers, streams, and ravines in the internal basins at risk of flooding, adding 90 sections with a significant risk of overflowing in cases of torrential rain—an additional 172 kilometers compared to the previous review in 2018. Eleven of these sections were added in the last year. The new sections are distributed across various basins in the region, such as the Ter-Daró, Tordera, Besòs, Llobregat, Foix, Francolí, and the streams of Montsià. With these additions, Catalonia now has 696.71 kilometers of flood-prone areas in 44 municipalities, as detailed this Wednesday by the agency's director, Josep Lluís Armenter, during an address to the Parliament's Ecological Transition Committee to explain the effects of the recent storm in the Terres de l'Ebre region. He also confirmed 26 defined coastal areas. "This gives us a much more complete picture of the current and future risk," he said. In Alcanar (Montsià), for example, the Bandolers and Llop ravines in the Serramar residential area have been added; as well as the Sant Jaume ravine and Rocatallada street in Les Casas de Alcanar; and the Forques ravine. All of these have overflowed in recent years, causing damage. The most recent flooding occurred just a month ago following Storm Alice. In this appearance, Armenter also stated that the Catalan Water Agency (ACA) plans to have a comprehensive and standardized map of flood-prone areas in Catalonia updated by the end of 2027, "which will be the basis for identifying new sections at risk of flooding." In this regard, three contracts have already been awarded covering more than 1,350 kilometers of rivers and more than 1,000 urban areas, with a total investment of over one million euros, he added. Half of the municipalities have plans

The review and update of the Preliminary Flood Risk Assessment (APRI) for the period 2028-2033—which President Salvador Illa assured would be expedited just days after the catastrophic storm in the Valencian Community—has expanded the areas of the territory where there is a potential risk of flooding. According to the Catalan Water Agency (ACA), significant flood events—those causing damages exceeding one million euros—recorded between 2005 and 2023 have been taken into account.

In these nearly twenty years, technicians have identified 45 such events, and Armenter stated that their inclusion will allow them to identify new sections at risk of flooding: "It's not immediate, and we'll do it in three phases." The first phase involves studying municipalities with more than 5,000 inhabitants, and the census will be ready by mid-2026. The second phase will cover medium-sized municipalities, with populations between 2,500 and 5,000. Finally, the smallest municipalities, with populations between 500 and 2,500, will be studied, covering a total of 1,350 kilometers of waterways by the end of 2027. The requirement to have current civil protection plans for floods has already led to their updates.

Of the 45 significant flooding events, 22 occurred between 2018 and 2023, revealing "a greater concentration of localized episodes of intense rainfall." Therefore, and for the first time, the agency has incorporated a clear definition of pluvial flooding, that is, flooding caused by intense rainfall that exceeds the capacity of urban drainage and sewage systems. According to the ACA, these events have been "key" to identifying new areas with a significant potential risk of flooding, considering not only possible economic damage, but also the impacts on health, the environment, heritage, and economic activity.

New technology project

To anticipate emergencies, Armenter announced that a new system is being developed to issue warnings at least two hours in advance, enabling emergency protocols to be activated. This project aims to provide a real-time prediction tool that simulates flood-prone areas with high resolution and integrates meteorological data, he explained. The Catalan Water Agency (ACA) is collaborating with the Barcelona Supercomputing Center (BSC), which will contribute intensive computing power, data storage, and technical support. "It's in the preliminary stages. It will be cutting-edge technology at the service of public safety," Armenter stated.