In late August 2005, Hurricane Katrina struck the coasts of the southeastern United States, causing over a thousand fatalities, hundreds of missing persons, and tens of billions of dollars in losses, including widespread destruction of New Orleans, a city that then had nearly a million inhabitants, caused by the flooding of more than 80% of its surface.
The impact of this event, in addition to being interpreted as an unequivocal sign of the climate change we are experiencing, led to the entry into the political agenda of a concept that, hand in hand with the multiplication of ravages attributable to the same cause in cities around the world, has gained more and more relevance: urban resilience.
We understand urban resilience as the capacity of a city to recover more or less quickly from an external impact, being able to maintain its functionalities. New Orleans, for example, had been slowly but continuously losing population since 1980 until it was hit by Katrina and, after a sudden drop of a third in the number of inhabitants, it recovered them until in 2021 it returned to the 2005 figure. Not only that, but it has continued to grow to exceed one million inhabitants today.
From this perspective, then, we can say that the city has shown considerable post-crisis resilience, since despite taking 15 years to recover population levels, it has even reversed the downward trend prior to the catastrophe. Today, moreover, the reconstruction works undertaken based on solutions more compatible with nature, such as floodable urban parks or the renaturalization of urban drainage, greatly reduce the risks of a new episode of Mississippi overflow while undoubtedly improving the city's capacity to face a subsequent recovery.
Currently, the concept of resilience applies to the consequences of both natural disasters and shocks of any kind, be it an economic crisis or a war conflict. Furthermore, it now implies not only the physical recovery of infrastructures and the urban fabric, or economic recovery, but also the recovery in terms of the social fabric and the mental health of affected people.
Transforming vulnerable cities into increasingly resilient cities is, therefore, a fundamental objective for adapting to the consequences of the climate emergency. This should be right now, in an increasingly urban world, one of the main concerns not only of political leaders, but of society as a whole.
And, it goes without saying, we have too recent the consequences of the DANA in central Europe and on the Iberian Peninsula, with the catastrophe of Valencia at the forefront, not to take it seriously. The lesson from Katrina and other similar catastrophes is that resilience is the result of good planning and the capacity for collective organization and response, with the State at the forefront.
We know perfectly well what needs to be done, or at least a good part of what needs to be done to achieve greater adaptation to the effects of climate change. First, review everything that is already in the planning that involves urbanizing flood-prone areas. In the metropolitan region of Barcelona these days, a dozen new projects in this situation have been pointed out, not counting urban centers, facilities (including schools and residences) and a good handful of key infrastructures (such as the airport, Mercabarna or the Maresme coast commuter line) that are threatened. It seems that strategic environmental declarations and flood reports are not enough, which, like planning in general, will have to be reviewed and updated to incorporate the dimension of new threats.
Secondly, reduce the urbanization of river spaces and their surroundings; redesign, deconstruct, depave, green, develop more nature-based solutions, put investment emphasis on green and blue infrastructures. In China, "sponge cities" are referred to as those, mainly those located in the deltas of large rivers, where massive investments have been made in this type of flood control actions.
These investments are costly, not very "visible" to the public, and cannot be deployed everywhere, with the same intensity, or in the short term. But we must be aware that having a network of storm drains like Barcelona's or large collectors like those in El Prat de Llobregat is often the result of decisions that go unnoticed, but can save lives.
And obviously, it's not enough to act only in cities. Cities should be the first interested in the good maintenance of river headwaters, with policies ranging from reforestation to guaranteeing activity that fixes population to take care of the territory.
Thirdly, although we have many plans, many projects (some, however, paralyzed once relegated in the order of priorities), many rules and many regulations in the right direction, it is necessary, as always, to enforce them and not find ourselves in circumstances like the current ones to realize that, of 531 municipalities obliged to have a civil protection plan in Catalonia, 237 have it expired and 60 have never done it.
Likewise, considering that these plans deal with aspects that can affect people's safety, they must be made understandable to the public. It is not enough to issue alarms when and how appropriate. A lot of education is needed in this regard, especially now that all kinds of conspiracy theories are triumphing on social media, and to explain very well what can and should be done and what not to do. Raise awareness, train, and inform, permanently, even when the threat seems distant.
As an anecdote that illustrates how much we need reliable information, I remember a radio talk show after the events of Katrina in which economist Xavier Sala-i-Martín argued that a similar episode in our country would have resulted in many more deaths, since poor people cannot as easily afford to buy a car as in the United States due to the fact that here they are more heavily taxed, so they would not have had a way to escape. As is known, in the case of Valencia, vehicles have been, actively (being in circulation) or passively (wanting to rescue them from underground parking lots), one of the main death traps for many victims of the DANA.
Transforming vulnerable cities into increasingly resilient cities is a fundamental objective for adapting to the consequences of the climate emergency.And it is precisely also on the mobility model, in this case of Valencia and its surroundings, that many eyes have turned following the tragedy.A mobility model based on private vehicles and suffering from the lack of metropolitan public transport coordination.As the president of the Sustainable and Safe Mobility Foundation, Pau Noy, stated, "Valencia has not equipped itself with any metropolitan governance, and without it, there is no transport policy, no territory management, nor prevention against the effects of climate change."
On this point of metropolitan management, the Interprofessional Association for Spatial Planning also issued a statement that, among other issues, raised: "The usual practice of urban planning as an instrument to mold the territory to the needs of increasingly complex societies finds limits in an excessively sectoral and non-integrated political-administrative logic, also excessively constrained by municipal limits that in no way adjust to the scale at which this type of risk acts, nor to the actions to be adopted by the actors in the territory (administrations, companies, civil society, and citizens)."
In this sense, everyone has highlighted the very important role played by mayors in this catastrophe, especially given the collapse of other levels of administration, but greater metropolitan organization seems more necessary than ever in this territory of 45 municipalities, 1.6 million inhabitants, and 640 km2 that Valencia and its surrounding municipalities occupy. The same reflection is valid for all large Spanish cities, among which, as we know, the metropolitan institution of Barcelona is the exception. Adequate articulation of governance is also fundamental to improving urban resilience levels.
In short, 2024 will close as the warmest year in history according to records, while also breaking the record for global CO2 emissions, and the temperature of the Mediterranean continues to rise year after year. The threat is real, making it seem quite unpredictable in all its dimensions, and therefore, homework must be done as soon as possible.
What defines us as a society is precisely how we react to situations like the DANAChance has wanted Valencia to be this year's European Green Capital, and as such it should show determination to the entire continent on the path towards greater resilience, reviewing all the points detailed above, investing in both urban and social repair. For example, taking into account studies that show that the most lasting psychological effects in this type of tragedy have to do with the loss of housing,it is crucial to focus efforts on the recovery of homes, knowing that there is no point in rebuilding where the catastrophe has occurred.
What defines us as a society is precisely how we react to situations like the DANA. Cities will be resilient to the extent that we are as a society, denouncing and combating ideological polarization and unsupportive behaviors and, above all, prioritizing collective solutions, breaking down barriers between disciplines and combining science and popular knowledge.