The State Railway of Thailand (SRT) acknowledged the issue, attributing it to accumulated dust within the tunnel. Despite pre-opening cleaning efforts using fans, dust continued to gather.
In response, the SRT has initiated a 14-day intensive cleaning operation, involving water jets and air blowers. The tunnel is expected to reopen on August 12th.
During the cleaning period, 14 passenger trains on the Ubon Ratchathani route will be temporarily rerouted to the old Mab Ka Bao-Pha Sadet-Hin Lap-Muak Lek route.
The SRT apologized for the inconvenience caused and assured passengers that the issue will be resolved promptly. The tunnel, a key part of the new Mab Ka Bao-Muak Lek double-track railway, is expected to significantly improve travel times and connectivity in the region.