For decades, the water reserve system of Barcelona and the metropolitan region—as well as that of the rest of the Catalan territory—has largely depended on a factor that humans cannot control: rain. When it rained, reservoirs—such as those of the Ter and Llobregat rivers that supply the metropolitan area—accumulated water that later allowed for guaranteed supply during drier periods. But the episodes of extreme drought in recent years have shown that it is not enough to wait for the rains to return to replenish reserves.
For this reason, the Barcelona Metropolitan Area is promoting the construction of new infrastructures to obtain water from different sources and reduce dependence on reservoirs. The new Estrella Drinking Water Treatment Plant (ETAP), inaugurated this Friday in Sant Feliu de Llobregat, is one of the first major pieces of this system change.
The plant, built by Veolia and operated by Aigües de Barcelona, will allow the metropolitan region's supply system to incorporate up to 1,000 liters per second of water from the Llobregat wells after an advanced purification process with reverse osmosis and activated carbon, a system that makes it suitable for consumption. The project has involved an investment of 45.9 million euros, approved by the Government of the Generalitat and financed through the tariff approved by the Barcelona Metropolitan Area (AMB).
Beyond its hydraulic function, the new plant also incorporates environmental criteria in its design. The facade will feature a vertical garden with native Mediterranean species with low water consumption, as well as elements to promote biodiversity, such as bird baths and feeders.
The relevance of this new infrastructure was also reflected in the institutional presence during the inauguration ceremony of this new plant, which brought together representatives of the main administrations involved, such as the president of the Generalitat, Salvador Illa; the consellera of Territory, Housing and Ecological Transition, Sílvia Paneque; the executive vice president of the AMB, Antonio Balmón, or the mayor of Sant Feliu de Llobregat, Lourdes Borrell. On behalf of the companies promoting the project, the CEO of Veolia, Estelle Brachlianoff, and the CEO of Aigües de Barcelona, Felipe Campos, also attended.
More water sources to prepare for future droughts
Beyond its specific capacity, the ETAP Estrella represents one of the first pieces of a broader strategy to reinforce the metropolitan supply system and reduce dependence on rain-dependent resources. Barcelona's water system already combines different sources: water from the Ter and Llobregat rivers, underground resources from aquifers, seawater desalination and, increasingly, the regeneration of treated water.
Behind this model are infrastructures such as the Llobregat desalination plant, in El Prat de Llobregat, which allows obtaining drinking water from seawater; the Sant Feliu Water Regeneration Station (ERA), which treats purified water for new uses; and now also the ETAP Estrella, which recovers the potential of water from the Llobregat wells.
But this new plant is just one of the planned actions to reinforce the system. The plans of the Barcelona Metropolitan Area also include the expansion of the reverse osmosis treatment of the Sant Joan Despí ETAP and the Besòs-Trinitat ETAP, which will increase treatment capacity by 800 liters per second.
A transformation that not only affects the metropolitan area of Barcelona, but is part of a broader strategy of the Generalitat Government to move towards a new water management model throughout the territory. The roadmap foresees that, by 2030, seven out of ten liters of water destined for domestic supply and economic activities will come from processes that do not directly depend on rain, such as regeneration, desalination or the use of new water sources.