The metropolitan beaches of Barcelona most affected by the latest storms have lost between 20 and 40 meters of width in just one month. This reduction in surface area has been accompanied by a large reduction in volume: in most of these cases the sea has carried away sand and a slope between 2 and 3 meters high has been produced.
This is the main result of the monitoring report that the Barcelona Metropolitan Area prepares monthly on the width record of all metropolitan beaches to optimize comprehensive management.
The most serious losses in width have occurred on the beaches of Les Barques de Montgat and Nova Mar Bella in Barcelona. These are the most important effects of the last 30 years. In the case of Montgat, since the breakwater was built in 1980, and with regard to the Nova Mar Bella beach, since the beach was built in 1992.
The successive storms Aline, Bernard, Ciaran and Domingos caused an atypical configuration on the metropolitan coast, with southwest winds and waves up to 4.5 meters high. This situation shook the western side of many beaches, which is the one most facing or perpendicular to the flow of dominant winds. On the other hand, on the eastern side of some beaches an increase in width has been detected due to the overaccumulation of sand derived from the southwest winds, to the windward of some breakwaters.
The increase in the frequency of storms in this case, together with the fragility of the beaches, implies an increase in sudden fluctuations in width, which make these natural spaces more vulnerable.
The report has been made by comparing the width measurements of the beaches made with GPS at two different times: mid-October and between November 6 and 15, to capture the effect that the storms have left.
We must hope that part of this loss of width can be regenerated naturally thanks to the dynamics of the seabed of the Catalan coast. However, the extreme drought situation also implies less natural contribution of sediments to the sea due to the decrease in the flows of the Llobregat, the Besòs and the Tordera, which are the three river axes that feed the sediments on the metropolitan coastline.
Dani Palacios, head of the AMB Beach Service, predicts that the natural recovery of the slope and width of the beaches could be slower than usual. “We are facing sudden changes derived from climate change, which makes it more difficult to predict the evolution and plan actions on beaches,” he explains.
The AMB continues working on the coordination of a stabilization plan for metropolitan beaches. Since 2017, it has carried out different previous studies to understand the dynamics and functioning of the coastline that serve as the basis for a resilience plan and for the projects of the Ministry of Ecological Transition.
The central government has launched a package of five projects with the aim of reversing the situation: in progress is the decontamination of the beach on the Sant Adrià de Besòs coast, which will reopen next summer season; in tender for the stabilization of Barcelona's beaches; in writing, the protection and stabilization of the beaches of Montgat; in writing: alternatives for the protection and stabilization of the beaches of the Llobregat delta; and in execution, the port of Barcelona is carrying out the x-ray of new sand deposits in the deepest areas of the coast of Barcelona so that in the future they will be a sand extraction area that can be contributed to both the beaches of the city as well as to the north of the capital and the Llobregat delta.
