Editorial: Darkness in the tunnel

Hopes have faded for the lives of eight men trapped inside a collapsed tunnel of the Srisailam Left Bank Canal (SLBC) irrigation project in Telangana. On Monday morning, ministers supervising the rescue operation reported some progress in rubble removal from the spot where the cave-in occurred but given that no contact has been established with the workers for nine days and no sign of their fate discovered, mood around the project site was distinctly gloomy.

The eight workers were carrying out maintenance work on the tunnel boring machine when a three-meter chunk of the roof gave in to an ingress of water and mud. While other workers scrambled to safety, this crew is thought to be either trapped on the other side of a 15 feet wall of mud or buried in it. There being no escape shaft or a holding area with enough air, the worst is feared.

Rescue personnel from 11 national agencies have been working non-stop to reach the workers but their task has been made immensely difficult by the continuing seepage of water, machinery entombed in the mud, and a broken-down conveyor belt. The 50-km SLBC tunnel bores through the Nallamala hills 150 m below ground level, passing through fragile rock formations and fault zones. So, it does not offer the option of digging vertically down to the disaster area unlike in the Silkyara tunnel rescue operation in Uttarakhand back in November 2023, when rathole miners managed to retrieve 41 trapped workers after 400 hours. Also, the depth here is too great to dig through and there is the risk of puncturing further pockets of water and triggering more collapses.

Moreover, the Silkyara disaster occurred about 200 m from the mouth of the tunnel, whereas the SLBC cave-in took place at the dead end of the operation, 14 km from the opening. Further, the Silkyara tunnel was a road project in dry terrain and had 2 km of breathing space for the trapped workers.

Whatever the conspiracy of factors, the Silkyara and the SLBC incidents both demonstrate the need for more robust risk management in infrastructure projects. Right after the Uttarakhand collapse, experts said it was a wake-up call for all tunnelling projects, especially those being undertaken in zones susceptible to climate change.

Union Road Transport Minister Nitin Gadkari announced then that a safety audit would be conducted of all under-construction tunnels in the country. His mandate was for roads but alarms ought to have rung for irrigation projects such as SLBC as well. If they did not then, they must now.

When the dust from this disaster has settled, the Telangana government must disclose whether the long-pending SLBC project was subjected to a rigorous geological analysis in recent months and whether there was continuing data monitoring at the site. This is also a good time to revise project management manuals and require contractors to adopt new technologies such as advanced warning systems, worker location devices, and on-site sensors for real-time monitoring of ground movement, water pressure, air quality, and other critical parameters.

Another dimension to work on is worker training. Since they have the most at stake, contractors must ensure that workers are trained in safety procedures and are provided with proper communication equipment. It follows that the government must hold the contractors responsible for this preventative aspect of safety.