Could a flood as catastrophic as the one in Valencia happen in Malaga?

Could a flood as catastrophic as the one in Valencia region of Spain happen in Malaga province? The clear answer is that yes, it could happen, but with nuances. The fact is that the two provinces have similar characteristics in terms of the behaviour of torrential rains, but also important differences that need to be analysed in order to give a well-founded response.

"I had never seen anything similar in all my professional life in terms of impact," admitted Jesús Riesco, director of the Aemet state meteorological centre in Malaga. Could so much water fall here? Anywhere; meteorology does not distinguish one area from another. Yes, it could fall, but this can happen every hundred years...".

However, the meteorologist emphasised that it is more likely that something like this would happen precisely where it has happened, on the eastern Mediterranean coast, "because the water is warmer and climatologically they have more intense rainfall situations in general, and with greater frequency. But it cannot be ruled out that such a brutal phenomenon could occur here".

"But logically, the frequency of such phenomena is very low, with a very long return period. It is very unlikely to happen, but it cannot be ruled out". The data is still being evaluated to determine the estimated time frame for the next flood of this magnitude.

Among the great rainfall records set by this episode in Valencia, Riesco highlights the 179.4mm in one hour, and up to 42mm in 10 minutes, "but not in terms of estimated intensity, but in terms of litres actually fallen". In Álora, on the same dates, some 200mm were also collected, but over the whole episode, while in Valencia they reached 618mm in 24 hours.

Added to this is the fact that the area affected by the Dana in the east was very extensive and densely populated, which is very different from the smaller places in the case of the Guadalhorce valley. "It is very unlikely that a similar event would occur again in Valencia, and for it to happen in Andalucía would be even less likely, although it cannot be ruled out".

In the meteorological sphere, the episode at the end of October has meant that this water year is now considered "normal". The rain gauge at Malaga Airport, the official Aemet rain gauge for statistical purposes, recorded 131mm (double the normal value, which is 61). And from January to October there have been 353mm, when the usual is 345mm. Therefore, this year is just within the historical average, when a week ago the deficit was half that.

"We have to get used to the fact that this is the way it is going to rain: fewer days but with more intensity. Between Easter and last week much of this year's water has been collected," he concluded.

"Of course something like this could happen in Malaga, a 98% chance", saidJosé Luis Escudero, an observer and meteorological expert in the province, who analyses storms and lightning on a daily basis on his SUR blog Tormentas y Rayos (storms and lightning). In his opinion, the key figure is the number of times the province has endured static storms, with recent cases in Campanillas, Campillos and Malaga city. It is true that these cases have been, for now, very limited to specific areas, but there could be one that occupies the entire district of Malaga.

Static storms linked to Danas have caused floods in many recent moments in history, from the 'riá' of 1907, to that of 1957, which left 300mm ; in 1969 (400mm) ; the famous 1989 floods and more recently in 2018 and 2020. "They are becoming more and more frequent", he warned, and refers to the cases of extreme weather that have also occurred in Madrid, Zaragoza, etc., in recent times.

A second key is that the city is criss-crossed by 90 streams, many of them taken up by streets and roads, and which would overflow in heavy rainfall. "Imagine where the cars would go. The Guadalmedina is not the problem because it is regulated, it's the streams that are the problem".

And the third is the high temperature of the sea water, which is fuel for these types of violent storms, as has been seen in Valencia. "In Malaga, it's almost 20 degrees today, in the middle of November."

"I don't want to be alarmist, but that's what happened in Valencia," he said and criticised the fact that Malaga is not prepared to deal with something like this. "We have to look for solutions, less cement, which makes the water run, and more green areas for the water to be soaked up. And there are many houses built in flood-prone areas," he said. "It may not happen for another 50 years, but if no action is taken it will be very serious."

Finally, Escudero calls on the institutions and the population to heed the warnings issued by Aemet. "They issued information and special warnings: it was said that the most likely was Tuesday, and the worst in Valencia. It was crystal clear."

The same question is answered by Enrique Salvo, botanist, professor and director of the climate change group at the University of Malaga (UMA). "Totally, totally. Let's remember what happened in 1983, with the bestial Dana that led to the bursting of the Tous dam. Here a debate was opened and it was believed that nothing would happen, thanks to the Limonero dam. At that time we forgot about the most important thing, which was the Guadalhorce. Six years later it happened here (1989)".

For the researcher, these droughts are going to be recurrent, above all, because the Mediterranean has changed a lot and is warming up at great speed. "It is a pressure cooker, especially in the Alborán, which will give rise to this and other types of natural catastrophes, which will increase. In fact, the big floods coincide with the period from October to December.

"There is no doubt that they are going to happen. The sea is getting warmer, and we also have an important mountain range next to the coast and this means that, as in the case of Valencia, a stationary Dana can discharge in this way. To make matters worse, we have the Guadalhorce river, which is a corridor for many of these intense squalls".

"And with a strong process of urbanisation, with housing in flood zones and without adequate planning for the 21st century, where we have already seen that climate change is a reality, as is evident again these days. The saddest thing is that these new urban developments are designed for the most deprived families and they are the most affected".

"The lesson we have to learn is that we need new territorial and urban planning and I see that the Junta de Andalucía is too focused on the western provinces and not enough on the eastern ones, especially Malaga, which has been neglected."

For the professor, the key is the Guadalhorce river and its environment, which requires intervention and regulation. "The reeds washed up on the beaches are a symptom of the fact that our riverside ecosystems are at a low ebb. He also draws attention to the fact that the turbulent, mud-laden waters are the result of a dragging of the vegetation cover, "which is tremendously rich, and which is lost due to the lack of forests".

Enrique Salvo also considers it urgent to have a green belt with species, following the ecosystemic model, "regenerating all the strata of the forest mass: arboreal, herbaceous and shrubby". At the same time, he proposes the construction of storm tanks on the outskirts of the city and the treatment of streams, rivers and canals, which cause the most material and personal damage.