Torrential rains and river flooding remain one of the greatest threats to many regions of Spain. From the north to the Mediterranean coast, municipalities and government bodies are launching dozens of projects to reduce the risk of flooding, while the scientific community warns that climate change will exacerbate the situation.
In recent weeks, several towns have announced river channeling, cleaning, and sewer construction projects. At the same time, European studies and projects point to the need to combine traditional infrastructure with nature-based solutions to address a problem that has become structural.
Channeling and protection works in different parts of Spain
In the Basque Country, the Basque Water Agency (URA) has completed the first phase of the channeling of the Ziako stream in Andoain (Gipuzkoa). The works, co-financed with ERDF funds, have allowed for the widening of the channel's hydraulic section and the removal of covered sections that restricted drainage . The project, which benefits approximately 14.700 residents, will continue in subsequent phases until it connects to the Oria River.
In the Valencian Community, the Villajoyosa City Council has put out to tender the Refoio ravine diversion channel, a €4,6 million infrastructure project that will divert floodwaters towards the Amadorio River . The project, with an 18-month timeframe, will protect the town center and unlock the development of 1.500 homes in the PP-4 sector. Mayor Marcos Zaragoza emphasized that this project is crucial for the safety of residents.
In Extremadura, the Cáceres City Council has begun cleaning streams and implementing strategies to clear vegetation along the Ribera del Marco riverbank, a €110.000 project funded by the regional government. Machinery is creating a retaining wall with plant debris to prevent flooding of orchards during high water. Mayor Rafa Mateos emphasized that this is the first phase of a comprehensive plan to enhance this natural area.
Millions invested to protect the coastline and river basins
A report by Seopan and Typsa estimates that €1.001,4 million in investment is needed in the province of AlmerÃa alone to address droughts and floods. Of that amount, €662,3 million corresponds to structural and green measures for flood risk management , such as the improvement of the Andarax River, valued at €162,2 million. Across the entire Andalusian Mediterranean River Basins region, the total investment amounts to €3.210 million through 2035.
These figures are in addition to the budgets for local projects. For example, the Andoain river channeling project has European co-financing, and the Villajoyosa sewer system is included in the municipal multi-year investment plan. The combination of European, regional, and municipal funds reflects the priority that local authorities give to flood prevention.
Science at the service of prevention and recovery
A joint study by the University of Granada, the Polytechnic University of Catalonia (UPC), and the University of Genoa, published in Communications Earth & Environment, warns that sea level rise will be the dominant factor in the risk of extreme coastal flooding on the Spanish Mediterranean coast during the 21st century. The researchers analyzed 1.600 kilometers of coastline and 17 climate projections, concluding that even if storms do not increase, rising sea levels will raise the probability of flooding.
Meanwhile, the CSIC is coordinating the European project FLOWSAFE, funded with €4 million from the Horizon Europe program. This initiative will develop tools that combine bioremediation, smart sensors, and artificial intelligence to restore ecosystems degraded by flooding . It will be tested in three pilot areas, including l'Albufera de València, which was affected by the 2024 DANA storm.
As an example of concrete solutions, researchers at the Spanish National Research Council (CSIC) have patented an antifungal composition that eliminates mold on surfaces after flooding. The treatment, initially designed for homes affected by the DANA storm, maintains its effect for at least 30 days and uses a combination of alcohols and quaternary ammonium salts, making it more effective and cheaper than commercial products.
Thus, between river channeling projects, multi-million euro investments, and scientific advances, Spain is tackling the challenge of flooding from multiple fronts. The combination of traditional infrastructure, nature-based solutions, and innovative technologies will be key to reducing risk and protecting the population in a context of increasingly pronounced climate change.
