Valencia flood: Early Warning Systems (EWS) offer more than just “response time”

Valencia, a city long accustomed to the threat of Mediterranean flooding, has endured events in the past similar to the one in 2024. One of the most significant occurred in 1957, when floods claimed at least 81 lives. In response to this tragedy, Valencia undertook an ambitious urban redevelopment project, diverting the course of the Turia River to the south of the city. This intervention remains a model of urban adaptation at both a European and global level, combining hydraulic risk mitigation with the valorisation of the old riverbed, now transformed into an urban park.

Despite this exemplary case of planning, the 2024 flood still resulted in significant casualties and revealed severe criticalities in risk management. This prompts a pressing question: how come a population with such a history of adaptation found itself so vulnerable? Without sufficient awareness, the citizens are unable to take essential self-protection measures—such as avoiding underpasses and underground spaces, refraining from crossing flooded waterways, and keeping a safe distance from bridges and embankments. Structural interventions like the Turia River diversion, while greatly reducing hydraulic vulnerability, can foster an excessive sense of security among the population. When mitigation measures are perceived as definitive solutions, there is a risk that the need for sustained vigilance and collective memory—maintained through public information campaigns and emergency preparedness—will be neglected. Furthermore, decades of relative climatic stability in the region may have contributed to a decline in risk awareness, leaving the population less prepared for extreme events such as the recent flood. Even the drought in the months leading up to the disaster may have influenced this awareness.

This brings us to the second—and most crucial—critical aspect that emerged during the Valencia flood: the coordination between institutional bodies within the framework of the Early Warning System (EWS). It is useful to retrace the key events, as reported by various media outlets, including POLITICO¹³. On the 25th of October, Spain’s meteorological agency, AEMET, began issuing warnings of a potentially historic storm. Over the following days, forecasts became more precise, and on the 28th of October, an “orange” alert was issued for several regions, including Valencia. Despite the severity of the situation, regional President Carlos Mazón chose to proceed with his official schedule and reassured the population, downplaying the risks. It was only after conditions worsened and AEMET issued a “red” alert that the first emergency measures were activated—but by then, the delay had already been significant.

One of the most serious criticisms centred on the delayed activation of the Es-Alert public warning system, which was meant to send emergency messages to mobile phones. The alert was not issued until 20:12, hours after the floods had already begun. The response was further hampered by political disorganisation, with the regional government delaying the emergency declaration until the 2nd of November.

The regional manager for emergencies later admitted that she had been unaware of the Es-Alert system, only discovering its existence at 8 p.m. on Tuesday the 29th—just as it began sending emergency alerts to residents. By then, eight hours had passed since the flooding began and ten hours since AEMET issued its “red” alert. This delay, coupled with the failure to evacuate promptly and the inability of the drainage infrastructure to cope with the heavy rainfall, hampered rescue efforts and worsened the death toll, which reached 224. And this, without taking into consideration the material damage to property and infrastructure. Only the central government approved various aid packages for individuals and businesses, amounting to 14.3 billion euros¹⁴.

In brief, the 2024 Valencia flood exposed significant flaws in the emergency response system, particularly in the capacity of translating weather forecasts into timely action. An external analysis revealed a fragmented structure on multiple levels. Firstly, there was a fragmentation within the scientific domain—between the National level of AEMET, which provides weather forecasts, and the basin authorities responsible for hydrological assessments and their consequent impacts on the soil. The hydrological evaluation was carried out with a delay compared to the availability of the meteorological one. Secondly, there was fragmentation between these scientific components—that translate into forecasting—and the civil protection component, which is responsible for the direct issuing of alerts to the public and for supporting political decision-making before and during such events. Finally, there seems to have been a fragmentation of responsibilities across the various territorial levels. Decentralisation is functional only when supported by effective, clear, and well-established procedures. In their absence, the system’s complexity increases, prolonging response times, which in these situations represent a crucial element—often the difference between tragedy and narrowly avoiding disaster. The civil defence system is a single unit that involves all the players in a scenario that must be well-understood, tested, and continuously improved through procedures, drills, and constant stress-testing—not only in times of crisis but also during “periods of peace”.