Travelers are not aware of this, but the Ferrocarrils de la Generalitat (FGC) station on Carrilet de l'Hospitalet avenue is submerged in the Llobregat delta aquifer. Although they have nothing to worry about, because it is as if they were entering a submarine, those responsible for the infrastructure do regularly monitor the pressure exerted by the water on the tunnel structure and the station.
The groundwater level in recent years has risen and would reach the height of the passengers' knees if it were not for the pumping system installed under the platforms that helps keep the liquid element at bay.
Despite this, the leaks have increased, to the point that they had to enable a small channel as a stream between the two central tracks of the station to evacuate all the water that entered from different points.
Now FGC wants to completely put an end to leaks by applying microcement injections from the tunnel between Cornellà and l'Hospitalet at all points where the risk of leaks is detected. The operators have been working every night since January, when the service is interrupted, injecting "a mixture of beach sand with microcement ten times finer than usual", as explained by Pere Mateu, project manager for the railway network of FGC. The works are carried out in a very limited way and with an electronic control system activated on the tracks to detect any deformation and guarantee that service can be resumed normally every morning.
Added to these surgical precision works is the construction this summer of a new 45-centimeter-thick vault, superimposed on top of the existing one, which reinforces the sealing of the infrastructure against water. In addition, it has been used to change the old tracks in a section of half a kilometer for new ones installed in concrete slab, a change that is made in all the modernizations of the last few years both by Ferrocarrils and TMB because it facilitates maintenance tasks.
Between one thing and another, it is expected to end the stream that runs through the station and keep losses from the aquifer at bay, a strategic reserve to draw on in times of drought. With the works in their final phase, Mateu calculates that "an Olympic-sized pool a day will be saved, the equivalent of the consumption of a city of almost 70,000 inhabitants such as Viladecans", to give an example that remains on the same aquifer.
The works, which have reduced the service in summer and involved a power outage for eight days, will be completed this weekend. With them, continuity has been given to similar work carried out a few years ago in Cornellà, where there were still more leaks. The intention of the railway company is to continue advancing from the Sant Josep station, in l'Hospitalet, to Plaza Espanya, to guarantee the shielding of the entire route against groundwater and delve into savings.
