Vázquez-Suñé et al 2006. Groundwater modelling as a tool for the European Water Framework Directive (WFD) application: The Llobregat case.

As I dig into the Llobregat River Valley, I found an interesting publication by a large team of Spanish/Catalan researchers modelling the lower Llobregat aquifer. This is a major source of drinking water for Barcelona and surrounding regions. Excessive pumping of groundwater has caused seawater intrusion, which threatens to pollute drinking sources.

The authors distinguish two aquifers in the Llobregat Delta: the Main Aquifer and the Upper Aquifer. The Main Aquifer is divided into three management administrations: Cubeta de San Andreu in the north, Vall Baixa in the center and the Delta.

One challenge for the modelers has been to obtain reliable recharge data. Infiltration from rain and irrigation are the main water sources. River discharge in the Llobregat is estimated at 15.7 cubic hectometers per year. Groundwater extraction from the Main Aquifer is 49.48 cubic hectometers per year. That is, Barcelona pumps 3 times as much water from the ground than what they see flow in the Llobregat River.

The authors recommend a reduction in groundwater pumping, and warn that current withdrawls are not sustainable. They recommend seawater barriers through the artificial pumping of treated wastewater into the aquifer along the coastal fringe. The model predicts that this water will be pumped to the surface again for urban treatment, and not be lost to the sea.

There is also fear that ancient landfills could become flooded if the aquifer recharges too much. This would exacerbate existing contamination problems. Therefore groundwater managers seek to keep groundwater high enough to prevent seawater intrusion, but not so high as to flood brownfields, or cause problems with underground infrastructure projects.


Vázquez-Suñé, E., E. Abarca, J. Carrera, B. Capino, D. Gámez, M. Pool, T. Simó, F. Batlle, J.M. Niñerota, X. Ibáñez. 2006. Groundwater modelling as a tool for the European Water Framework Directive (WFD) application: The Llobregat case. Physics and Chemistry of the Earth. 31: 1015-1029. [Article]