Four professional colleges (Road Engineers, Agricultural Engineers, Industrial Engineers and Economists of Catalonia) have recovered the proposal to interconnect Catalonia’s regional water networks to face the crisis unleashed by the drought. A public manifesto proposes to link the regional network of the central area of ??Catalonia with that of the Consorci d’Aigües de Tarragona, which manages the water of the Ebro. For the signatories, the interconnection of supply networks is the ideal formula that will allow sufficient additional resources to be available in periods of intense drought such as the current one and those announced for the future.

The promoters of this initiative highlight that the existing infrastructure for the supply of high water in the internal basins of Catalonia “are not sufficient to guarantee the supply”, so, consequently, “it is necessary to forge agreements” in relation to solutions that must provide “resilience and flexibility” to water cycle systems. The document does not ignore the difficulties that this entails and points out that “an appropriate governance model must be sought to guarantee fair and equitable access to water for everyone.

Currently, the reservoirs in the Barcelona and Girona region are at 17.5% of their maximum capacity, and the forecast is that when they fall below 16% they would enter the emergency phase, a situation that could occur in the middle of the month of January, according to the current forecasts of the Catalan Water Agency.

The proposal of these professional colleges was presented this Friday in a debate held at the College of Roads, Canals and Ports through the Intercollegiate Water Observatory, which brings together the representatives of all these colleges (Engineers of Roads, Industrial Engineers, Agricultural Engineers and Economists).

Specifically, the Observatori Intercol·legial de l’Water launches the idea of ??recovering the old project to give continuity to the “minisvase” from Ebre to the Barcelona region, taking advantage of the fact that not all of the water concession granted in its area is being used. day by law (approximately 2.4 m3/s of the 4 m3/s granted).

The idea is that this connection would only be operational “in exceptional cases of drought”, such as the current one. Also, in the opposite direction, it could carry water from the Ter-Llobregat system to Tarragona in the event that episodes of contamination were recorded in the Ebro due to cyanobacteria, attacks, repair works or other emergency situations, according to the explanations given by the engineer. Albert Vilalta who has coordinated these works.

The technical proposal highlights as an advantage the fact that the technical construction projects are already available (dating from 2002 and 2008), which would allow the bidding for the work to be accelerated. The route would run on a 65 kilometer route from Constantí to El Vendrell and then continue to Olèrdola, where it connects with the ATL system. Half of this route is already available.

In total, about 50 hm3 of the approximately 200 hm2 in which the water deficit has been estimated in the entire central region of Barcelona could be available. “This would be the way to save time while waiting for the two new desalination plants to be available,” which have a completion horizon for 2027/2028, as explained by engineer Albert Vilalta.

The works would last approximately 18 months, so that the new infrastructure would be ready for use by 2025.

Its implementation would require the approval of the Ebro Hydrographic Confederation, upon request from the Consorci d’Aigües de Tarragona. It would require, however, a modification of the state law of the ‘ministravase’ of 1981, in which a geographical limit was established to take the water of the Ebro limited to the province of Bacelona, ??while in the proposed case it entered the from Barcelona

The authors of the proposal consider that the interconnection of basins is the most effective solution for the supply system to be resilient in crisis situations. They insist that this infrastructure would be used only in cases where there is a lack of resources in the internal basins of Catalonia, which would allow for a “cushion” of security in supply. However, they specify that in any case the need to maintain an ecological flow as an essential element would be taken into consideration.

Likewise, they judge that the contribution of new resources not dependent on the natural water cycle should continue to be promoted; Therefore, they appeal to continue increasing the resources of regenerated water to be reused indirectly, as is already being done, and add new desalination and

In parallel, they estimate that the effectiveness of water management must be improved to reduce losses in pipelines, especially in agricultural uses.

The Intercol·legial Water Observatory is closely monitoring the extraordinary actions that are being carried out by the Administrations since the approval of the law on extraordinary and urgent measures of the month of September to address the situation of drought approved in September.

This is not the first time that it has been proposed to connect the supply network of the Ter-Llobregat system with that of Tarragona. This idea began to take shape at the beginning of 2008, when a deep drought caused the level of the reservoirs to drop below 20%, without there being either desalination plants or regenerated water, resources that today account for 58% of the water consumed in the country. the 23 municipalities served by Aigües de Barcelona.

The solution was put on the table after the tripartite government failed in its attempt to transfer water from the headwaters of the Segre River to the Llobregat basin. This attempt to “temporarily and reversible capture” the Segre ran into opposition from the Spanish Government, largely due to fear of criticism from Valencia and Murcia (theoretical recipients of those resources promised by the PP in the early 2000s in the National Hydrological Plan) in a complex electoral context.

Already before that refusal, the Catalan government opened the possibility of extending the Ebro mini-transfer (which now serves the central regions of Tarragona) to Barcelona through an already built 14 km pipeline to connect Cunit with Cubelles.

The idea was to transfer a part of the allocated water but it was used in Tarragona, since it only used between 70 and 80 of the 120 hm3 annually). However, given the flow limitations of the existing pipeline, the construction of a wider diameter pipeline was proposed that would run parallel to the AP-7 from Tarragona to Olèrdola (to link with ATL).

Finally it was agreed that the transfer of Ebro water to Barcelona would not be permanent, but would only work during emergency periods. On the other hand, this connection would be reversible, that is: in the future Tarragona could receive water from Barcelona if necessary.

The Government proposed a UTE (Temporary Business Union) to develop the project. AGBAR asked to play a key role in the process and presented a proposal to carry out the project in 6 months.

The project was awarded for 164 million euros to a joint venture of 6 companies, led by AGBAR with 20% of the capital, and with the participation of Sacyr, Copisa, Dragados, Acciona and Comsa Infrastructuras. However, May 2008 was the wettest in 30 years in many places in Catalonia, which substantially altered planned emergency procedures, including the transport of water by boat from Marseille and Tarragona.

This is how Hug March (UOC) and David Saurí (UAB) remember it in their study The drought of 2007-2008 in the city of Barcelona: genesis, management and discordant visions