Lack of safety standards will hamper tunnel safety audit in India

In the wake of the tunnel disaster at Uttarakhand, while the central government has decided to conduct a safety audit of 29 under-construction tunnels in India, it turns out that there is no dedicated safety unit with the National Highways Authority of India (NHAI) for such projects. The position is similar with the other large road and tunnel building organisation, the Border Roads Organisation.

Neither has the Comptroller and Auditor General apparently conducted any audit ever to assess safety issues in such projects, satisfying itself with only checks on the money spent in the projects. In fact, India does not have its own standards of tunnel safety, depending instead on the British Standards-06164 issued in 2019.

On Wednesday, the government announced a safety audit of all 29 under-construction tunnels across the country. “NHAI officials, along with a team of experts from Delhi Metro Rail Corporation (DMRC) as well as other tunnel experts, will inspect the ongoing tunnel projects and will submit a report within seven days”, a government release said. These projects include 12 in Himachal Pradesh, 6 in Jammu and Kashmir, 2 each in Maharashtra, Odisha, Rajasthan and one each in the states of Madhya Pradesh, Karnataka, Chhattisgarh, Uttarakhand and Delhi respectively.

NHAI has a road safety cell headed by Member (Technical) which examines the risks of traffic accidents on India’s rapidly growing road network. In May 2022, NHAI also issued a Road Safety Audit Policy. The Policy mandates a “formal systematic and detailed examination of a road project by an independent and qualified team of auditors”. Under the Policy, 22 companies have also been empanelled. But their job is to investigate road accidents and suggest preventive measures, not the build-up of risks in a construction project.

“The cost of including a rigorous set of safety measures in a highway project with tunnels is not more than 2 per cent of the total project cost,” said Rajat Mishra, Chief Executive Officer (CEO) and Director of Efkons India, a 100 per cent subsidiary of Strabag, a global leader for building highways and tunnels.

But in the race to capture projects with razor-thin differences in quotes, the companies sacrifice even this margin. A tunnel costs roughly about Rs 500 crore per km to build. Mishra said Strabag has a fatality of just 2 from out of the over 3000 tunnels it has bored across various terrains in the world, but that comes with high adherence to safety standards.

In India, of the 50 plus tunnels under construction (of at least a kilometre and more) by roads and metro railway companies, the focus is on finding the cheapest method to do so. Tunnel experts said there are two common methods to bore these channels. The Earth Pressure Balancing Machine (EPBM), as its name suggests, is painstaking and typically keeps the balance of the earth pressure intact as the machine drills holes in the ground. Some of the metro projects like Bengaluru have invested in it, since they pass through densely constructed areas overhead. The pace of construction is slower but avoids risks like the one at Uttarakhand.

For instance, the prestigious Atal tunnel in Himachal connecting Manali with Spiti valley had a huge water body over the course of the tunnel. The engineers had to create a nullah to drain out the water before proceeding with the excavation. This procedure raised the cost of the highest highway single-tube tunnel above 10,000 feet (3,048 m) in the world to Rs 3,200 crore.

The more popular one is the micro blasting under what is known as the New Austrian Tunnel Method (NATM). This one, a blasting and digging method, is deemed faster and is used to cut through hillsides as in the Himalayas. The risks are that if an adequate number of pillars are not made to support the walls, there could be a cave-in as the tunnel goes deeper. It happened in the current disaster.

To analyse these issues, engineering major L&T had set up a Tunnel Excellence Academy in Chennai a few years ago. As of now, it is the only one to do so in the country. The problems are obvious. The graduates from this school are sought after by rival construction firms.

India-based construction companies have to make provisions for external auditors and internal auditors to inspect the safety of their projects. These, held twice a year, are supposed to show the weakness in the tunnels and other construction methods. “No agency pulls up a company for not complying with the safety standards. The punishment scale is severe but hardly enforced,” said a senior industry veteran. He suggested less severe but certain penalties as a better deterrent. NHAI, which brought in a new safety policy for punishing contractors for faulty construction of projects, has pulled up some for road safety issues but not implemented it for any tunnel-related ones. Neither has the railways done so.