24% of all Spanish aquifers are overexploited. “In poor quantitative condition”, according to official jargon. The extraction of water above the recharge limits of these natural deposits has made it possible to put into irrigated production large areas of land where it was unimaginable to develop this type of economic activity.
The keys to understanding why the Mar Menor is in danger
In the wake of this possibility, to the water withdrawals authorized by the administrations, hectares and hectares of land have been added that, without permits, have also drilled, pumped and irrigated farms. The WWF organization has tracked the extent of this “water looting” attached to four aquifers: Los Arenales, Doñana, Alto Guadiana and Campo de Cartagena. The results are a panoramic photograph of the groundwater theft.
“The water and agricultural authorities have not been able to control the expansion of extractions, adding to the overexploitation from legal wells that already existed a large number of illegal catchments without a recognized right of use,” concludes their study. The price: this water is prevented from nourishing ecosystems such as Daimiel or Doñana, the door is opened to contamination of the aquifers with sea water, the surrounding land sinks and “an agricultural surplus that has produced very significant decreases in perceived prices. by the producers due to the excess supply, dragging the agricultural exploitations in dry land into the abyss “.
Los Arenales: there is also irrigation in the northern Meseta
The Los Arenales aquifer extends through the provinces of Segovia, Valladolid and Salamanca through three underground masses: Los Arenales, Medina del Campo and Tierra de Vino. 77,900 hectares of irrigated crops benefit from this liquid: a third do not have the right to use that water: 23,900 hectares that extract about 97.99 cubic hectometres per year for these exploitations, according to the estimates of this work.
So, according to the review of the mapping of farms with authorization and the calculation of water used by these extensions by the type of crop with which the pirate farms work, 55.99 hm3 per year are removed from the underground mass of Medina del Campo outside the permits, from Los Arenales 31.3 and from Tierra del Vino another 10.68. In principle, all that volume has no protection to be used. “It represents around 30% of the aquifer’s available resources – which is 321 hm3 per year – which reflects the degree of overexploitation”, concludes the WWF analysis.
For what do you use it? Well, almost half of the 23,900 hectares illegal They are planted with spring herbaceous crops and the other large part for high endowment summer herbaceous crops (beet, potato, onion). The latter are the ones with the most water they drink each season: 71 of those 97.9 hm3. There is a small portion of 800 ha for vineyards.
What is the impact? WWF considers that these hectares are the main responsible for the overexploitation of the aquifer. The deterioration of the underground water reservoir is noticeable in the surface ecosystems that are connected to it: the Trabancos and Zapardiel rivers see their flows and the contributions to the lagoons and wetlands of the Place of Community Importance of Los Arenales go down.
Campo de Cartagena: a bureaucratic labyrinth in which irrigation hides.
Around the Campo de Cartagena aquifer (Murcia Region) a bureaucratic labyrinth has been woven that favors lack of control. There are farms that do not have rights of exclusive use of groundwater, but they are not considered illegal exploitations because they were irrigated before the current Hydrological Plan: they have consolidated the use of water within a geographical area that the authorities have called the Agrarian Demand Unit (UDA ).
So the WWF investigation has not been able to apply the map of farms with legal water rights, but rather it is necessary to look for the surface that comes out of that UDA. However, in the specific case of Campo de Cartagena – which is behind the unbridled ecological decline of the Mar Menor – the Ministry of Ecological Transition has calculated that some 8,460 hectares of irrigated land are irregular (its preliminary estimate was somewhat higher).
But, to add a little more confusion, in the Region of Murcia a distinction is made between the area under irrigation and the area that is actually irrigated. It is because the same farm can have up to three annual crops each with its water requirements. Furthermore, “it is not possible to know the origin of the water used within the UDA”, highlights the work of WWF.
With all that cocktail, those 8,460 that the Segura Hydrographic Confederation assumes are 20% of the official irrigation surface. The estimate of water extracted without authorization is around 8-9 hm3 each year.
The consequences: it is perhaps the most famous case. The constant pressure of intensive irrigation, and even more so if it is illegal, directly affects the recharge of fresh water from the Mar Menor lagoon. A huge amount of agricultural fertilizers has traveled in that water, resulting in the eutrophication of the lagoon and the ecological disaster that the episodes of green soup of 2016 or the massive deaths of fauna in 2019 and 2021 due to the unbalanced ecosystem.
Guadiana: overexploitation of decades
The Alto Guadiana aquifer in Castilla-La Mancha encompasses three masses: Mancha Occidental I and II and Rus-Valdelobos. Overexploitation, including accumulated legal permits, goes on for decades. The official declaration took place in 1988 and the final one in 1995. However, in 2019, WWF was able to detect 51,465 hectares of irrigated land outside the authorized maps. It is 29% of everything that is irrigated with that water, whether authorized or not.
The estimated water for this area amounts to 92 hm3. An extra damage that is added to the overexploitation allowed by the irrigation authorizations that have been accumulating in that area. The Hydrological Plan in force establishes a maximum of 199 hm3 for this aquifer and the consolidated rights total 250 hm3.
What is watered? Most of them are woody crops in which the vines play a leading role. “A structural situation of overexploitation is taking place that has been consolidated through several restructuring plans of the vineyard and the planting of other woody crops in the area and that is difficult to correct and manage in drought situations,” the study concludes.
The impact: the Tablas de Daimiel National Park is in a critical state of conservation. In fact, it survives on the basis of transfusions of water pumped from emergency wells dug to prevent it from drying out completely and self-igniting its peatlands. “This situation derives from the disconnection between groundwater and surface waters due to the drop in aquifer levels,” reiterates WWF.
Doñana: the boom of red fruits next to the World Heritage Site
Around Doñana, a World Heritage Site, there is a great variety of irrigated crops. They are fed by the aquifers of Doñana and Aljarafe. WWF’s calculation is that 4,700 hectares were irrigated without authorization in 2020. That meant the extraction of 21 hm3 of water without permission that year. Roughly, 60% of that area went to woody crops such as fruit trees and 30% to crops under plastic: the boom of red fruits such as strawberries or blueberries.
What is watered? Of the water masses associated with Doñana, 1,200 hectares of crops under plastic outside the official cartography are fed by La Rocina (9 hm3 are extracted illegal) and another 800 hectares of woody plants draw water from the Almonte mass. They have also detected 255 hectares of irregular irrigation on the Marismas mass. These three aquifers were declared in poor qualitative condition in July 2020. The European justice condemned Spain last June for not protecting Doñana from the plundering of water. The magistrates understood that, precisely, illegal extraction should have been taken into account when estimating the pumping of the aquifer.
In addition, the Aljarafe aquifer (north and south) is drilled to feed an additional 2,000 hectares of intensive crops, which means, in total, 6.8 hm3 of water without a permit.
The impact: Direct damage to the groundwater flow has already been detected, which should reach the permanent and seasonal lagoons located in the peridunar zone of the Marismas de Doñana National Park. The lack of water supply causes this priority habitat to be in decline. Likewise, “the decrease in the water table has an impact on the conservation of plant formations in the areas of Los Cotos, says the NGO.