From the Ebro to the Muga: the engineers' plan to gain water in case of drought

BarcelonaAfter three years of severe drought, Catalonia is breathing a sigh of relief. Reservoirs have recovered their levelsRestrictions have been relaxed and the emergency is no longer imminent. The Water Observatory of Catalonia—comprising the professional associations of civil engineers, agricultural engineers, industrial engineers, and economists—welcomes the government's progress in preparing water infrastructure for future emergencies, but on Thursday it reiterated its flagship proposal: the interconnection of water networks on both sides of the country, from the Ebro River to industrial areas and the Muga River, for redistribution. According to its proponents, the Catalan government "is already aware" of this plan. The project, known as the water corridor, is based on creating a flexible, bidirectional network that allows for a rapid response to water emergencies. "It's about having a flexible network, supplying water when needed to the areas that require it," explains Pere Calvet, dean of the College of Civil Engineers (CECCP). In short, this is not a system of fixed water volume transfers, but rather a mechanism for timely and reversible support throughout the territory. In fact, the Observatory prioritizes three actions that should serve as the backbone of the future Catalan water corridor. The connection between the Tarragona Water Consortium (CAT) and the Aigües Ter-Llobregat (ATLL) system is based on an interconnected water corridor model, with a proposed maximum flow rate of 1.5 m³/s. This connection would hinge on the development of the Cunit desalination plant—which would reinforce the supply to the southern part of the Barcelona Metropolitan Area—and reduce dependence on the Ebro River in the Tarragona region. The second proposed connection is what they call the northern branch, which should guarantee the water supply for the Girona, Fluvià, and Muga regions, which are more prone to the effects of future droughts according to projections from the Meteorological Service of Catalonia. In drought episodes, like last year and the year before, the Sau-Susqueda-Pasteral system can reach critically low levels, and there is no alternative source of drinking water. The Observatory's proposal would be to connect these basins with the rest of the Catalan system, ensuring a continuous supply. These two projects would cost around 600 million euros. The organization is optimistic and indicates that once these two axes are consolidated, they will consider leveraging the modernization of the Urgell canal to establish a link with Lleida. This third connection, which they emphasize is still under study, would allow the use of surplus water or irrigation water from Lleida's lands as a strategic emergency reserve for areas of the country at risk of drought. As with the other interconnections, they insist that it would not imply "any permanent water transfer," but rather would be a one-off mechanism to "strengthen water solidarity between territories."

Desalination plants, key

In these projections, the construction of desalination plants is a determining factor because it allows for flexibility in the system and truly bidirectional connections. The Catalan government has commissioned the state-owned company Acuamed to expand the Tordera plant, which will not be operational until 2030. Meanwhile, the Foix desalination plant is pending approval and could be operational from 2031 onwards. In this regard, the Observatory warns that the future will require strengthening the country's own executive capacity. "Now that we are no longer facing an emergency and short- and medium-term actions are focused, it is time to consider the main water network with a 2050 vision, prioritizing sustainability criteria. We will do so steadily and surely," states Carles Conill, president of the CECCP Water Commission.