Himalayan tunnel collapse: safety in the spotlight

Recounting his 17-day ordeal waiting to be rescued from the 4.5 kilometre-long road tunnel that collapsed during its construction in Silkyara in the Himalayan state of Uttarakhand, Vishal Kumar, a native of the hill state of Himachal Pradesh, said the first 24 hours were extremely difficult and scary for the 41 workers. “We did not know if anyone knew we were trapped or if anyone was coming to help us… a lot of thoughts were running through our heads,” he told the news agency ANI after being rescued.

Kumar was one of the 41 workers trapped inside the tunnel. The collapse of a short segment of the tunnel between Silkyara and Dandalgaon on the Brahmakhal–Yamunotri highway in the early hours of 12 November occurred after a landslide in the mountainous area. This caused large amounts of rubble and debris to block the tunnel entrance, trapping the workers.

The families of the trapped men faced an agonising wait, with many gathering outside the tunnel entrance for days offering prayers. Visiting the site, the union minister for road transport and highways, Nitin Gadkari, said the rescue teams were “facing challenges due to the complex and fragile geology of the Himalayas. The mountain is loose and fractured at the site.”

Photograph: iStock, Harry Cooper Photography

Although the rescue operation was expected to be straightforward and completed within only a couple of days, a series of technical setbacks resulted in a lengthy delay in reaching and freeing the trapped men. The workers were eventually rescued on 28 November after several attempts by regional, national and international agencies, and individuals, especially ‘rat hole’ miners, individuals skilled in digging narrow tunnels large enough for one person to enter and excavate coal, a practice banned in India since 2014 but which continues illegally to this day. During the final stretch of the mission, around a dozen rat-hole miners took turns digging through rocks and debris, using hand-held drilling tools after sophisticated heavy-duty machines broke down.

Inspection of all tunnel projects

Following the tunnel collapse, the National Highways Authority of India (NHAI), which builds and manages the country’s major highways, was ordered by the central government to inspect all tunnel construction projects across the country.

“To ensure safety and adherence to the highest quality standards during construction, NHAI will undertake a safety audit of all 29 under-construction tunnels across the country,” said the authority in a statement.

The audit will examine 12 tunnels in the Himalayan state of Himachal Pradesh, six in the Jammu and Kashmir region, and various tunnel projects in Uttarakhand, the northern Himalayan state where the Silkyara tunnel collapsed.

The Silkyara tunnel is being built in the district of Uttarkashi as part of the Char Dham project, a Rs 12,000-crore highway expansion project designed to widen 889 kilometres of hill roads to improve access and connectivity to four major Hindu pilgrimage shrines – Badrinath, Kedarnath, Gangotri and Yamunotri – in Uttarakhand in the upper Himalayas. The project is a flagship initiative of Prime Minister Narendra Modi, who laid the foundation stone for the first phase of the road-building work in Dehradun in December 2016. Modi dedicated the Char Dham project to the victims of floods in Uttarakhand in June 2013 that claimed thousands of lives, promising that a road network for pilgrims, which was resilient to disasters, would be built.

In a series of tweets, Modi stated the Char Dham highway project will create over 900 kilometres of roads and provide a major boost to tourism in the Himalayan area of north India. “Adding of bypasses, tunnels, bridges and flyovers will ease travel,” he said on the X platform, previously known as Twitter. “Proper slope stabilisation will ensure protection against landslides.”

Commenting on the circumstances surrounding the collapse of the Silkyara tunnel, Anshu Manish Khalkho, director (admin and finance) of the National Highways Infrastructure Development Corporation Ltd (NHIDCL), the central government-owned body in charge of the tunnel’s construction, said: “Around 19–20 minor to medium level collapses occurred during the construction of the tunnel,” according to a report by The Times of India. 

“Such incidents happen during every tunnel construction project but we were unlucky this time as workers got trapped,” he added.

However, another official connected with the building of the tunnel, who preferred to remain anonymous, reportedly told The Times of India: “The tunnel had faced numerous cavity collapses due to the challenging geology of the region and significant rock deformation.”

Environmental concerns

Although the Indian central government and supporters of the Char Dham project say the construction of the 800 kilometres of roads and the tunnel will ensure year-round, hassle-free travel for pilgrims to the shrines, environmental campaigners and locals claim the heavy drilling and construction has led to landslides and heavy environmental damage in the vulnerable Himalayan region.

The Himalayas are the world’s youngest mountain range and were formed as a result of the collision between the Indian Plate and Eurasian Plate which began some 50 million years ago. Some commentators say the local landscape is therefore geologically unstable and prone to seismic activity, which could increase the risk of a tunnel collapsing during its construction.

Experts claim the Char Dam project involves scientifically-unsound construction activities that have increased the risk of landslides, flooding and related disasters in the Himalayan region. They argue that the construction of the road, and related projects in the region, like the building of dams for hydroelectric power plants, threatens to further upset the local ecosystem, warning that lessons have not been learned from floods that claimed several hundred lives in recent years in the valleys of the Rishi Ganga and Dhauli rivers in Uttarakhand.

In January 2023, Vimlendu Jha, a leading environmentalist and the founder of Swechha, a sustainability campaigning group, posted on X, formerly Twitter: “Char Dham road project is a disaster, with non-stop landslides, cutting down of thousands of trees, changing the course of perennial and seasonal rivers and streams, damaging the aquifers, a complete mindless design, made for ‘FAST’ and ‘CONVENIENT’ mobility of tourists and armed forces.”

Following the recent tunnel collapse, he posted on X: “I had talked about the DISASTROUS Char Dam project and the insane digging of tunnels in the Himalayas, and how such so called development projects are like digging your own grave, in an ecologically sensitive zone.”

Ecological experts and environmental campaigners have long claimed that the Char Dham project will increase the risk of subsidence of homes, landslides and flooding in the Himalayan region, arguing that the area’s fragile geology and damage to local ecosystems from construction work means there needs to be greater assessment and scrutiny of the risks involved, the construction methods used and the likely environmental impact of the road building. They also argue that climate change is increasing the frequency, intensity and likelihood of extreme rain events in the Himalayan region, and together with the impact of the various construction projects, this potentially increases the risk of floods and landslides in the area.  

Lack of environmental impact assessment

However, experts say that while major construction projects like Char Dham are meant to be subject to an environment impact assessment (EIA) that explores the environmental, social and economic impacts of the project before it is approved, the EIA process was by-passed by the authorities.

An EIA compares various alternatives for a proposed major engineering project and predicts and analyses all the possible environmental repercussions under various scenarios. An EIA is also used to identify appropriate strategies to mitigate the environmental, social and economic impacts of a major construction project.

In 2018, the Citizens of Green Doon (CGD), a citizen-led group that campaigns to protect nature and the environment in and around the city of Dehradun in Uttarakhand, submitted a formal complaint to the National Green Tribunal (NGT) arguing that the Char Dham project had not undergone an EIA and calling for its cumulative impact to be assessed before it was given approval.

However, in an affidavit to the NGT in 2018, the central government stated that pre-project environmental clearance under the 2006 EIA rules is only required for the construction of new national highways and the expansion of existing highways that are over 100 kilometres long.

However, critics say that because the Char Dham project was divided into several small stretches separated by 16 road bypasses, it was classed as multiple small projects of under 100 kilometres, which allowed permission for the entire road to be granted without a full and formal environmental assessment.

Roads widened to 10 metres

In 2019, India’s Supreme Court formed a committee to investigate the environmental impact of the Char Dham project and to suggest ways of minimising the environmental risks. Although campaigners argued that the width of the hill roads should have been limited to 5.5 metres due to the potential environmental impact of cutting roads through the Himalayan slopes (such as a potentially higher subsequent risk of landslides), the central government argued that 10-metre wide roads should be built, with two lanes in each direction.

The Supreme Court eventually ruled that 10-metre-wide roads could be built, after the central government argued that the construction of roads and helipads by the Chinese on the Chinese side of the Himalayan border meant that for security reasons, 10-metre-wide roads were needed in Uttarakhand to allow for the swift movement of Inda’s armed forces in the event of any security issues.

However, campaigners say that building wider roads leads to more damage to the surrounding forest and mountains.        

Possible geological fault

Commentators have also alleged that the geological surveys carried out before work began on the Silkyara tunnel may have been insufficient or inadequate, and media reports have suggested that possible causes for the tunnel collapse include a geological fault.

It has also been reported the tunnel did not have an emergency exit, which hampered efforts to free the trapped workers. Himanshu Thakkar, an engineer from IIT Mumbai and the coordinator of the South Asia Network on Dams, Rivers and People (SANDRP), said: “Why was there no escape passage built, despite government guidelines recommending emergency exits for tunnels longer than 1.5 kilometres?”

In a televised interview, Dr Jagdish Telangrao Sahu, a member of a high-level government committee responsible for framing rules for tunnel design, construction and maintenance, emphasised the importance of appropriate safety provisions, such as escape tunnels during all phases of a tunnel project, for both the workers excavating them and the eventual end-users. 

According to media reports, Bernard Gruppe, a German-Austrian engineering consultancy that provided design services to Hyderabad-based Navayuga Engineering, the construction company that holds the contract for the tunnel construction project, said in August that since “the start of tunnel driving, the geological conditions have proved to be more challenging than predicted in the tender document”.

A leading geologist, Professor CP Rajendran, stated that in regions like the northern Himalayas, where is a potentially higher risk of seismic activity like earthquakes, it is vital that large-scale construction projects do not impose excessive forces on the terrain as the projects may prove unsustainable in the long term. Another geologist argued that potentially haphazard and irresponsible construction in the Himalayan hills is likely to create an imbalance in the landscape, leading to further problems.

Although plans are now underway to resume construction of the tunnel, with an emphasis on additional safety measures, a team of experts from the central government that was due to arrive at the site on 30 November to review the safety of the tunnel structure before work recommences did not arrive. Uttarakhand government officials said there was no information about when the team might show up.

Earlier, V K Singh, Union minister of state for road transport and highways, said that a high-powered committee of experts would carry out a “security audit” of the project, without specifying
a date.

Meanwhile, after undergoing a 48-hour medical observation, all the 41 workers were discharged from hospital in Rishikesh. The hospital administration confirmed that all the workers had been cleared as “physically fit”, and their mental wellbeing was also being monitored.