The summer of 2022 was the warmest in Spain since 1961, when records began to be kept. Last year, the temperature exceeded the average for 1981-2010 by 2.2ºC. This increase in heat, together with the lack of rainfall throughout the year, left the reservoirs under minimum: At the beginning of the summer they were at 49% of their capacity, 20% below the average for the last ten years.
In these circumstances, and with temperatures expected to continue to rise, one of the main concerns of the impact of climate change is water scarcity. How to deal with a long-term drought?
Andalusia and Catalonia, with low hydrological reserves
In 2023 the data no longer allow us to be optimistic. The state of the hydrological reserves is a concern, adding to the situation of 2022 an alarming shortage of rainfall during the winter. In fact, according to data from the Ministry of Ecological Transition, reservoirs are currently at 50.5% of their capacity. Data that, although better than at the beginning of 2022, are well below the average for the last ten years which is 62.7%.
Even though the alert is widespread throughout Spain and we are considered to be in a situation of meteorological drought, there are areas that are especially critical. As expected, the regions in the south of the mainland present lower figures. These include the Guadiana basin, at 34.7%, the Segura, at 35.8% and the Guadalquivir at 25.6%, compared to 74% for the Duero, 78.5% for the Miño-Sil and 84.9% for the Eastern Cantabrian.
Within this context, the state of the internal basins in Catalonia is especially worrying as they are only at 27.2% of their capacity due to the situation of prolonged drought, with 29 months with hardly any rain.
Possible consequences of a prolonged drought
There is no doubt that one of the key challenges in the coming years will be the management of water resources and measures to address scarcity. Of the consequences of a prolonged drought, desertification deserves special mention: According to a report by Nature, 75% of the territory in Spain is already at risk of suffering a process of desertification due to irregular rainfall, rising temperatures and soil abuse.
As can be imagined, if the effects of this drought are not mitigated, the consequences would be terrible for life, with a serious impact on flora, fauna and a number of areas of human activity.
1. Water consumption restrictions
The clearest consequence of a prolonged drought clearly involves restrictions on water consumption. Reservoirs intended for consumption, both for people and for agriculture, are at 42.6% of their capacity according to government data.
As was already experienced in many areas during the summer of 2022, water cuts will become increasingly frequent to save this resource. Priority will be given to the use of water for direct consumption, restricting the irrigation of public and private gardens, the filling of swimming pools and other non-essential uses.
2. Agriculture in times of drought
Water scarcity will also have a direct impact on agricultural production. For example, at the end of February the Regional Government of Catalonia established a 40% reduction in water consumption for agricultural activities for the coming months. If the situation does not improve, there could be more restrictions after the summer.
If we take into account that Spain is the main exporter of fruits and vegetables throughout the European Union and the third in the world behind the United States and China, a decrease in the volume of crops would have a serious impact not only on the diet in Spanish households, but throughout the world.
3. Production of electricity
In Spain, hydropower is the second source for renewable energy production, representing 26% of total production in 2021. It is also one of the best options to reduce the impact of the price of gas. However, like other water reserves, dams for electricity are also at a lower level. In this case, the average is 67.9% of their capacity, below that for the last decade.
Fortunately, the production of hydraulic energy is fully compatible with other priority uses, such as human consumption and the irrigation of market gardens, because during the process it is neither altered nor restricted.
Even so, the use of water from reservoirs to generate electricity is controlled by the State Administration, as is the management of all other water reserves. So if limitations or restrictions are imposed to address water shortages, energy production will also be affected, and this will affect energy prices.
Santiago Domínguez, head of operations and maintenance in hydroelectric plants for Enel Green Power España, warns that "the level of reserves in the form of snow is unusually low (below half of the reserves to date in an average year). So it is foreseeable that the thaw will contribute a volume of water to the rivers significantly lower than in previous years, which would seriously affect the availability of water in the summer months and, possibly, will require some of our plants to be shutdown. "Everything will depend on the abundance of rains in the spring that is beginning now."
Solutions to prevent water scarcity and mitigate its consequences
With all this, it is clear that we urgently need to continue working on improving early warning systems and risk management to find solutions to these climate events, which will be increasingly extreme and unprecedented.
The most common measures are the cuts and restrictions on water consumption, which are being implemented in many parts of Spain and in Europe. In addition to the examples shown above, in other neighbouring countries such as France, Germany and Italy, urgent hydrological plans are also being prepared to deal with the situation.
But in addition to the restrictions on consumption to economise on the use of this scarce resource, medium and long-term solutions need to be sought to deal with such a prolonged drought. One of these solutions is the Strategic Project for Economic Recovery and Transformation (PERTE in Spanish) for the Digitalisation of the Water Cycle. The objective of this tool is to make use as efficient as possible, both in urban areas and in agriculture and industry.