Right on the border between the provinces of Malaga and Granada is one of the most amazing places in Spain. The Cliffs of Maro-Cerro Gordo is a system of caves, cliffs and semi-enclosed beaches that attract tens of thousands of tourists every year. The levels of sunscreen in the water are so high that they not only pose a "significant danger" to marine biodiversity, but also to human health.
This is just one of the 48 examples of environmental disasters included in the 'Black Flags warning' report by Ecologistas en Acción. Although the report presents some methodological problems (and has components more typical of a communication campaign than a technical analysis), the problem exists and goes far beyond it. Spanish beaches are a central resource for the country's largest industry and, unfortunately, they are poorly managed. How long will they be able to withstand the rate of degradation to which people subject them?
The coastal problem, in figures. "More than 50% of the beaches and 70% of the dunes on the Spanish coast are degraded or profoundly altered; 60% of the wetlands that existed in 1950 have disappeared; more than 60% of the immediate surroundings of the beaches on the Mediterranean, southern Atlantic and archipelago coasts are urbanized", this analysis by Miguel A. Losada, professor at the University of Granada, is already a decade old, but it has not lost any of its relevance.
This is quite important as the human degradation Losada is talking about is added to natural erosion. "A phenomenon that affects 70% of the coasts around the world," explains Jorge Guillén, a researcher at the Institute of Marine Sciences in Barcelona. "A beach in equilibrium is one in which the sand that leaves and the sand that arrives have a similar volume; those are very atypical; normally they tend to grow or disappear." The latter is what happens to hundreds of Spanish beaches and what forces them to spend huge budget resources to move sand from one side to another.
Why is this happening now? It is not something new. The phenomenon of beach growth and disappearance is something that has been happening for millions of years; the difference is that now it affects (a lot) the economy. Especially because the sediments that reach the sea (and, therefore, circulate along the beaches) are substantially less now than before. There are four factors for this: the first is the reservoirs. Spain has 1300 operational reservoirs. This means that the amount of sediments that used to be carried by the rivers to the sea is much less due to alterations in their courses.
The second is the urbanization of the coast. As mentioned above, up to 70% of the dunes are highly degraded and up to 60% of the wetlands have disappeared. Both dunes and marshes were systems that "fed" the natural cycle of the beaches; moreover, they were systems that protected the coast from erosion: the accelerated urbanization since the 1960s has destroyed a large part of these systems.
Third, the 'traditional' solution to these problems (i.e., the construction of harbors, dams and breakwaters) in turn alters sediment transport capacity. And since they are usually built with a local perspective, they often cause problems on a regional scale. And finally, also linked to environmental management problems, there is the "massive destruction of posidonia meadows in the Mediterranean since the 1970s". Uncontrolled discharges into the sea have damaged the structure that fixed it.
The countdown begins. In this context we’re like a snake: historically, the efforts to maintain the beaches have ended up contributing to increasing the problems. And this is only the beginning. If extreme weather events continue to increase (as everything seems to indicate), the disappearance of beaches will become much more common (and the budget dedicated to stop it, increasingly larger).
We have lived (and built a huge industry) on something we thought was "renewable" and unlimited. Now we are beginning to see that this is not the case. It is no longer just that climate change may eventually drive summer tourism off our beaches. It is that now we are beginning to see that we need more and more resources to save the natural sites from tourism, fishing and hotels. If we don't do it (or if we don't change the current tourism model) the black flags will end up taking over the entire coast.