A crack under the track forces to cut for a month a section of the L2 of the metro

BarcelonaMobility headaches seem to be unstoppable when it comes to accessing Barcelona. The problems have now also reached an infrastructure that had proven more reliable until now: the metro. A crack in the slab on which the tracks rest, caused by the pressure of groundwater in a tunnel between the Artigues-Sant Adrià and Sant Roc stations, will force the closure of the metro line 2 section between Gorg and La Pau from November 2 to December 3.

TMB CEO Xavier Flores explained that after the heavy rains at the beginning of October, inspection services detected a crack at a point inside the tunnel that caused the ground to shift slightly. The crack, caused by the pressure from the rising groundwater level, is right at the point where there is a switch, one of the most sensitive parts of the network.

At first, TMB's decision was to limit the speed of trains in this section to 15 kilometers per hour and disable the switch to reduce friction. The speed limit has resulted in a reduction in the number of trains that can circulate per hour in that section, which has led to crowding this week at various stations in the area, such as Badalona-Pompeu Fabra. "We apologize to users because this is not how it should be," said Flores, although he stressed that "safety is above all else."

After analyzing the crack and monitoring any ground movement, TMB has finally decided to cut off train circulation in the area for a month to be able to repair the crack more quickly. The procedure will consist of injecting cement to close the fissures in the invert—the structure that, together with the diaphragm walls, supports the tunnel—and improve its resistance to water pressure. Once the foundations are renewed with these cement injections, the slab on which the track is installed will be replaced.

Flores, who explained that the closure will be used to make other improvements to the tunnel, has assured that no other point in the network has been found where there have been cracks due to groundwater pressure. In this sense, he wanted to send a "message of reassurance" and has assured that they are monitoring the infrastructure to act immediately as soon as any incident is detected.

Mobility alternatives

In order to carry out the entire operation, TMB expects the service suspension to last one month, although Flores has admitted that if the work proceeds at a good pace, it is possible that the deadlines will be shortened. Meanwhile, an alternative transport plan has been designed to minimize the impact of the suspension on passengers. Beyond the other metro, bus, or tram lines that can help cover part of this route, a shuttle bus will also be put into service between the Gorg and La Pau stations.