Corrosive flows, faulty materialities: Building the brine collector in the Llobregat River Basin, Catalonia

The history of hydraulic infrastructures is plagued with failures often with catastrophic consequences. Although the agency of water in disasters has been widely documented less well known are the substances in water such as salt that may cause infrastructural collapse and harm humans, flora and fauna. In the Llobregat River Basin (Barcelona), a 120-km long pipe transports salt-saturated wastewaters produced in the potash mines of central Catalonia to the Mediterranean Sea. Conceived as a technological fix to reduce river water salinization, the brine collector started operating in 1989 and succeeded to cut by half the concentration of salts in river waters. However, as the extraction of potash salts increased the brine collector soon reached its full capacity and became prone to leaks and ruptures that poured salt-saturated flows into the rivers and adjacent lands. Moreover, the reduction in salinity achieved was not enough to prevent the need of salt-removing technology for the drinking water plants supplying Barcelona. The brine collector understood as a sociotechnical system assembling material, discursive, organizational, and institutional components proved the fragility of rules and regulations addressed to manage salt pollution in the basin. More fundamentally, the assemblage constituted by the collector showed how the interplay between private (the mining company) and public (the regional water agency) organizations has resulted in the successful shifting of impacts created by salt from the private to the public sphere in economic, health, and environmental terms.