The last permanent lagoon in Doñana disappears due to drought and overexploitation of aquifers

The Santa Olalla lagoon, the largest permanent lagoon in Doñana and the last one that has held water in August, “has finished drying up” and these days “it has been reduced to a small puddle in the center, where the aquatic birds”, as warned by the Higher Council for Scientific Research (CSIC). In a statement released this Saturday, the scientific agency has indicated that this is the third time that it has happened since the Doñana-CSIC Biological Station began recording data on the natural space in the 70s of the last century. From the CSIC they highlight that Doñana “historically has been a refuge for fauna”, and has an important system of lagoons, of which only a few are kept with water all summer, offering refuge to the first wading birds that they migrate to the south after breeding in the north of Europe, and they also constitute the habitats of a good number of strictly aquatic flora and fauna species. In addition, in summer the rice fields also offer an important refuge. “But things have changed. Doñana no longer has any permanent lagoons, while the area of ​​rice fields planted this year is a third of normal due to the lack of water”, explained the director of the Doñana-CSIC Biological Station, Eloy Revilla. AN INTENSE PERIOD OF DROUGHT From the CSIC they explain that the drought that Europe is suffering, “especially intense” in the Iberian Peninsula, “is wreaking havoc in the natural space”, but they warn that “the most worrying thing is that this comes from afar ”. “It’s been years since it rained normally. Doñana has had precipitation levels below average for ten consecutive years”, says Revilla. Wetlands and the species that depend on them, such as waterfowl, are “particularly affected” and are “forced to move in search of areas that maintain available water in the hardest times of the dry season.” The Santa Olalla lagoon is the only one that was maintained with permanent water from a string of large lagoons –the peridunares lagoons– that form in the lee of the “impressive” chain of dunes that separates the marsh from the Atlantic Ocean. Its origin is in the discharge of water from the Doñana aquifer in this area, which generates an “explosion of life”. These and other natural values, according to the CSIC, have made Doñana considered a National Park and Biosphere Reserve. However -they add from the Higher Council for Scientific Research-, “the continuous exploitation of the aquifer by intensive agriculture and extraction for human consumption, also in years as dry as this one, means that not only the lagoons temporary ones have disappeared from Doñana, but also the permanent ones are threatened”. THE OVEREXPLOITATION OF THE AQUIFER, “MAIN PROBLEM” From the CSIC they add that the peridunares lagoons are known to be mainly affected by the water withdrawals of the population of Matalascañas, which in summer increases its water consumption exponentially with the arrival of tens of thousands of tourists and that makes the population go from a few thousand inhabitants to about 100,000 people. The effect of water consumption by tourists is so intense, according to the CSIC, that the piezometers -the wells that measure the depth at which the water level of the aquifer is found-, detect the differences between the days of the day and on weekends, when consumption is “much higher”, and they even identify the difference between day and night, when people sleep and use less water. “This is the third time that the Santa Olalla lagoon has dried up completely since we have records. It also happened in 1983 and 1995, in both cases also coinciding with periods of intense drought”, explained Eloy Revilla. The director of the Doñana Biological Station added that “we know, from the times that have happened before, that it is not only the drought that has caused the permanent lagoons in Doñana to have disappeared”, since “the overexploitation of the aquifer in Doñana is also responsible”. From the CSIC they point out that “an aquifer is overexploited when more water is extracted from it than it recharges when it rains, something that has been happening in Doñana for many years.” The Technological and Singular Scientific Infrastructure –Doñana Biological Reserve, dependent on the Doñana Biological Station CSIC–, has installed a monitoring camera in the lagoon to see its evolution in the coming days. On August 31, Santa Olalla was “dry, parched and cracked, reduced to a tiny puddle of water and mud.” “Surprisingly”, as pointed out by the CSIC, on September 1, “after many people have already returned to their homes, it is observed that some springs and springs sprout again from which the largest permanent lagoon of Doñana”. Faced with this “serious situation” in which the Santa Olalla lagoon finds itself, the director of the Doñana-CSIC Biological Station asks “that the measures be accelerated to eliminate the underground water intakes of Matalascañas, and that, in the meantime, Restrictions are imposed on the use of water in the urbanization, at least in years in which the lagoons are in situations as extreme as this one”. “It cannot be that while the grass in Matalascañas continues to be watered, the Doñana lagoons dry up completely”, Eloy Revilla concluded.