Thanks to L&T, India’s maiden Bullet Train Corridor is speeding towards completion, writes Bappaditya Paul

 

CONTEXT: India took a big leap in 1853 when the country’s first railway line opened between Bombay and Thane, marking a watershed moment in its transportation history. Since then, numerous railway lines have been constructed across India, and the expansion continues.

 

Fast-forward 173 years to 2026, India will witness another watershed moment when a 50-km priority stretch of the Mumbai–Ahmedabad High Speed Rail Corridor – aka the country’s first Bullet Train Corridor – is thrown open.

 

The Corridor is 508 km long: 156 km in Maharashtra, 4 km in Dadra & Nagar Haveli and 348 km in Gujarat. It will take off at Mumbai’s prime business district, the Bandra-Kurla Complex (BKC), and culminate at Sabarmati in Ahmedabad, Gujarat.

 

There will be 12 stations along the route – BKC, Thane, Virar, Boisar, Vapi, Billimora, Surat, Bharuch, Vadodara, Anand, Ahmedabad and Sabarmati. The stretch between BKC and Thane (21 km) will be underground, including 7 km passing under the Thane Creek. The remaining stretch –  from  Thane to Sabarmati – will be elevated and will feature 7 mountain-tunnels.

 

The Bullet Train is designed to reach a speed of 320 kmph. With stops at all stations, the journey from BKC to Sabarmati will take about 2.58 hours; with stops at select stations, the travel time will be reduced to 2.07 hours.

 

The National High Speed Rail Corporation Ltd (NHSRCL) – a Government of India enterprise – is the implementing agency for this biggest infrastructure project undertaken in India. The project utilises the Japanese Shinkansen technology.

 

NHSRCL has awarded contracts for various components of the project to multiple entities, including L&T. The contracts were awarded at different points in time over the past few years, and the construction commenced in December 2020.

 

Of the 508 km Bullet Train Corridor, L&T alone is constructing as much as 468.24 km – that is, the stretch from Thane to Ahmedabad. That’s an impressive 92%.

 

Out of the 12 stations, nine – Thane, Virar, Boisar, Vapi, Bilimora, Surat, Bharuch, Vadodara and Anand – are also in L&T’s scope, and so are seven depots – Boisar, Vapi, Surat, Bharuch, Vadodara, Anand and Sabarmati.

 

Additionally, L&T has also been awarded the contract for laying 115 km tracks from Vadodara to Sabarmati, and for the electrification of the entire 508 km route.

 

Three L&T verticals – Heavy Civil Infrastructure, Transportation Infrastructure, and Buildings & Factories are involved in the execution of this monumental project.

 

 

It’s 8.30 pm and raindrops are falling gently over Zaroli, a forested village straddling the Maharashtra-Gujarat border. The downpour, coupled with an all-encompassing dusk, has lent the village a more remote look than it actually is.

 

There isn’t a soul out on the narrow motorable road that cuts through the village and terminates on the foothills of a mountain. Our cab stopped on the foothills.

 

With Mohanbabu S, a Digital Officer with L&T’s Heavy Civil Infrastructure vertical, leading the way, we trudged up the muddy mountain slope while shielding ourselves with an umbrella.

 

Up on the mountain, the ambience is dramatically different! It’s a beehive of activity inside a tunnel 350 metres long and 12.6 metres in diameter that has been bored through the mountain.

 

A group of L&T workmen and engineers, toiling under blazing halogen lights, are diligently casting the tunnel walls to secure them against future rockfalls. The scene buzzes with energy, reminiscent of a bustling peak-hour shopfloor!

 

“Rain or sunshine, day or dusk, our work never stops. We operate in shifts around the clock to complete this tunnel through which the Bullet Train would pass,” says Patitpaban Panda, as he guides the workmen in setting up the formwork for concrete casting. With decades of experience in tunnel construction, Panda embodies L&T’s expertise in driving the project.

 

The tunnel at Zaroli is situated 156 km from the Bullet Train Corridor’s starting point in Mumbai. L&T has bored the tunnel by undertaking controlled blasts and is now focused on giving it finishing touches.

 

In all, there are 7 mountain tunnels along the 468.24 km stretch that L&T is executing. Barring this one in Gujarat’s Valsad district, the remaining 6 are in Palghar district of Maharashtra.

 

In addition to the tunnels, L&T’s stretch also involves construction of 25 major and minor river bridges, notably the ones spanning the treacherous Narmada River in Gujarat’s Bharuch and Tapi River in Surat.

 

Recognising the challenges and the tight deadlines associated with this critical infrastructure project of national importance, L&T management strategically handpicked seasoned engineering leaders from across the conglomerate and entrusted them the task of spearheading this landmark project.

 

For instance, G Vinod of Heavy Civil Infrastructure, the Task Force Leader (TFL) overseeing construction of as much as 237 km, is a veteran with over three decades of experience in metro rail construction. He was brought in from the ongoing metro rail project in Mauritius that L&T has been executing in phases.

 

Navneet Kaul, known for his proactive approach, is another key resource working shoulder-to-shoulder with G Vinod as the Head of Technical Services.

 

Also, round the leadership team, there is another dynamic TFL in Arvind Ramkrishna Nerurkar who is responsible for 135.45 km, while the ever-meticulous M Ramesh is the TFL overseeing another 87.5 km.

 

Each Task Force Leader is supported by multiple Project Directors and Project Managers, who themselves are accomplished engineers with proven track record spanning over 20 years.

 

In a nutshell, L&T has literally mobilised a regiment of engineering commanders to home in on the Bullet Train Corridor.

 

And ask them about the biggest challenge in this project, and all of them respond in unison: “To envision and dare accomplishing a project of such mammoth scale in just about five years.”

 

“If you look at the Delhi Metro, the 350-odd km network has been constructed across 25 years. That’s an average 14 km per year. Here, we are constructing almost 10 km every month,” they say. This comparison to Delhi Metro is particularly relevant because, it too has a mix of underground and elevated routes, albeit with a maximum designed speed of 135 kmph as compared to the Bullet Train’s impressive 320 kmph.

 

 

 

To realise this monumental dream of the Bullet Train Corridor, L&T has devised several innovations – focusing on machines, materials, and methods – hitherto unheard of in India.

 

Before commencing the construction, L&T needed to conduct a physical survey of the Bullet Train alignment to map topographical variations and identify physical hindrances, if any. Conducting a manual survey even by deploying a large team of technicians to the field would have taken about 90 days.

 
To expedite the process, what L&T did is, it opted for an innovative Light Detection & Ranging (LiDAR) using helicopters and, completed the survey of 118.55 sq km in just 15 days.

 

In a LiDAR survey, GPS (Global Positioning System), INS (Inertial Navigation System) and camera are mounted on the bottom of a helicopter. As the helicopter flies, a laser emits light pulses towards the ground and a sensor detects the return of these pulses, to calculate the ‘time of flight’. The camera automatically keeps on capturing photographs.

 

The combination of laser, GPS, flight parameters data and the photographs generates an accurate survey data. The data, in this case, was used to prepare a detailed design of the Bullet Train alignment and to identify the right-of-way requirements for project affected plots/ structures, etc.

 

Notably, L&T employed its own Group Company, LTIMindtree, to conduct the LiDAR survey – undertaken for the first time for a railway project in India.

 

The next stage in the project involved understanding the nature of the soil strata along the Bullet Train Corridor. The mandate was to dig over 2,454 borewells along the alignment and test, in just 12 months, around 1 lakh soil samples collected from them.

 

“But the problem was that the cumulative capacity of all accredited soil testing facilities in India was insufficient. So, what we did was, set up our own temporary GeoTech Lab at Surat to accomplish the job,” says Tiruvuri Srm Srinivas, a General Manager with L&T’s Heavy Civil Infrastructure, responsible for project coordination.
 
Spread over 58,000 sq ft area and equipped with 474 automated machines, it was Asia’s largest GeoTech Lab which operated from June 2021 to March 2024. The lab was manned by 190-odd technicians supervised by 20 geotechnical experts, and it set a record by completing 94,000-odd running meters of geotechnical investigation in just a year.

 

At a specific location in Vadodara city, the Bullet Train Corridor crosses over the Ahmedabad-Vadodara Expressway. For this, L&T was required to make pile foundations in the middle of the ever-busy highway for constructing the piers.

 

Conventional pile foundations require larger working space to perform static load test on a group of piles and for constructing the pile cap. But given the space constraints on the arterial highway, L&T made use of a Japanese method called Shinso Pile, which does not require a pile cap and hence needs much less working space.

 

“Shinso Pile is a unique method  that we have implemented for the first time in India with highest quality and safety standards,” says M Ramesh of L&T’s Transportation Infrastructure vertical, who is overseeing the construction of the Bullet Train stretch from Vadodara to Ahmedabad.
 
Another innovation devised to expedite the Bullet Train project is the adoption of Full Span Launching Method (FSLM) for viaduct construction, instead of the conventional segmental construction.

 

A first-of-its-kind approach in India, in FSLM, the entire 40-metre-long span of a viaduct is precast in a yard, transported to the actual site using a Straddle Carrier and then placed over the piers with the help of a Girder Transporter, Bridge Gantry and Launching Girder.

 

L&T has set up yards at every few kilometers along the Bullet Train alignment to precast the viaducts required for the stretch it is constructing.

 

Establishing the casting yards adjoining the alignment was a must for implementing the full-span construction. Special efforts went into identifying the plots at desired locations, bringing multiple owners on one platform, convincing reluctant parties to lease out their land and finally formalising the lease agreements.

 

It was a humongous task involving around 1,000 acres spread over 20 locations, and this laid the foundation for FSLM implementation.

 

“By opting for Full Span Launching, we have been able to expedite the construction by 8-10 times – and that’s huge for a project where every minute counts,” says G Vinod.

 

L&T has also developed in-house most of the strategic equipment being used in the construction, track laying, and allied jobs. These include the Straddle Carrier, Launching Girder, Track-slab Layer, Rail Feeder Car, CAM injection car, etc.

 
Seismic Stoppers and Seismic Dampers are mechanical devices that negate damages to a bridge during extreme conditions, such as an earthquake, by dissipating the kinetic energy of seismic waves that penetrate a structure. They are installed in between a pier and a viaduct. To ensure safety, NHSRCL is also installing 28 seismometers along the Bullet Train Corridor.

 

“The Corridor is being designed to withstand high seismic waves. We were supposed to import the Seismic Stoppers and Seismic Dampers from Japan. Since that was time consuming, we got them manufactured in-house by L&T’s Heavy Engineering vertical at Hazira in Gujarat,” says Navneet Kaul, while rushing for a review meeting with senior NHSRCL officials.

 

It goes without saying that real-time round-the-clock monitoring is vital when one is constructing such a mammoth and monumental project against a tight deadline. But on commencing the work, L&T discovered that there are many pockets along the Bullet Train alignment that have either very poor or no internet connectivity at all.

 

“We reached out to all the major mobile telcos, but they declined to put up the required  communication infrastructure unless a certain number of subscribers was guaranteed. So, we set up our own Point-to-Point or P2P Network over a publicly available frequency band,” explains Mohanbabu S.

 

To establish the P2P Network, L&T’s project teams set up 33 towers of 30 metres height and 700 CCTV cameras in the yards, crushers, site offices and along the alignment across a 324.5 km stretch. This has brought about a 1,000-acre area under 24x7 live monitoring – accessible to Project Directors/Project Managers and at the central control rooms that L&T has set up in Surat and Vadodara.

 

 

 

At a precast yard in Navsari, Gujarat, Arya Lakshmi is busy supervising the casting of Noise Barriers and Cable Ducts for the Bullet Train Corridor. Hailing from Kerala, she joined L&T as a Graduate Engineer Trainee (GET) last year and now supervises 400-odd workmen engaged in precast operations.

 

“NHSRCL has mandated the installation of 2.4-metre-high concrete noise barriers on both sides of the Bullet Train Corridor to mitigate the noise that trains moving at 320 kmph are likely to generate. To expedite the process, we are pre-casting the noise barriers at the yards and then transporting them for installation,” Lakshmi explains.

 

As an excellent example of women empowerment, the noise barrier production at L&T’s Karjan yard in Vadodara district is supervised entirely by a team of women engineers who joined L&T as GETs – either last or this year.

 

“Not all young engineers get an opportunity to work in a landmark project like this. We are fortunate,” says Nihala Azad, the factory in-charge who leads a team of nine women.

In contrast to the messy, open-air construction that we are used to seeing, it’s amazing to witness how several lakhs of noise barriers and cable ducts are being precast in a largely mechanised shopfloor-like set-up – be it at the precast yard at Navsari, Karjan or Nadiad (near Anand).

 

Even more fascinating is the Precast Factory that L&T has established near Anand in Gujarat for casting the track slabs.

 

Barring the preparation of the reinforcement cage by workmen, all other tasks – concrete pouring, curing, watering and shipment – are mechanised and require little manual intervention.

 

“This is a facility of which we are very proud” says an ever-amiable Akula S Phanendra Kumar of L&T’s Transportation Infrastructure vertical. “Even officials of the Japan International Cooperation Agency (which is funding the Bullet Train project) were impressed.”

 

Kumar is a Project Director overseeing the laying of 115 km of the Bullet Train tracks – from Vadodara to Sabarmati – which is in L&T’s scope. This involves casting the track bed over the viaducts, placing track slabs over it, and then laying the rails, thus accomplishing the ballastless standard gauge track that NHSRCL has selected.
 

 

 

The Vishwamitri River made headlines during the recent floods in Gujarat, after crocodiles from its overflowing channel forayed into Vadodara city. The same river has posed an unforeseen challenge for the Bullet Train Corridor.

 

In its original plan, NHSRCL provided for a minor bridge over the Vishwamitri in Vadodara because it runs through the city like a narrow canal. However, during monsoons in the last few years, the river has been overflowing, and this has necessitated reworking the bridge design altogether.

 

L&T is constructing a major bridge for the Bullet Train over the Narmada River in Bharuch. It’s a 1.2 km-long bridge, and to erect the piers, as many as 25 well-foundations are required, mostly in the river itself. The well-foundations will reach depths of up to 77 metres – taller than the Qutub Minar!

 

Due to excessive rainfall upstream, in September 2023, a huge volume of water was discharged overnight from  the  Narmada Dam. This washed away a 600-metre temporary access bridge (TAB) that L&T had constructed over the river to facilitate construction of the well-foundations.

 

“We were informed about the discharge the previous evening and hence were able to at least move out several costly equipment just in time. But the damage to the TAB significantly affected our operations,” says Project Director VBSPK Chakravarthy of L&T’s Heavy Civil Infrastructure.

 

The soil strata of Narmada River at the site also varies widely and can be deceptive. As a result, the project team had to customise the designs of each of the well-foundations and take additional measures that were not originally planned for.

 

In addition to such challenges, the Bullet Train project poses a few more dares that evoke more amusement than concern.
 
Similar to the recent floods, Gujarat experienced a deluge in July 2022. Karjan, a small town about 38 km from Vadodara city and 106 km off the Shoolpaneshwar Wildlife Sanctuary, was among the places affected. L&T has a project office at Karjan for the Bullet Train Corridor.

 

Waters from the overflowing Vishwamitri River, infamous for being infested with crocodiles, inundated the nullahs and crop fields of Karjan.

 

On one of those flooded mornings, weathering the rains, C Sivakumar, Project Director with L&T’s Heavy Civil Infrastructure, reached the Karjan project office – only to encounter what he had never imagined! A crocodile was resting right at the reception lobby!
 
“To us, that was more amusing than scary. Colleagues joked that the croc came to mark its attendance on our facial attendance system,” says Sivakumar, bursting into laughter.

 

While forest officials took away the magnificent reptile, L&T subsequently hired two wildlife rescuers to cater to the project jurisdiction overseen by the Karjan office. To date, they have rescued 15 crocodiles, 2 leopards and 55 snakes from the project alignment and its vicinity.

 

 

 

L&T has deployed around 31,350 workmen  and  3,350  staff  in the Bullet Train project – a workforce that surpasses the overall employee strength of many companies in India.

 

The outcome – as of this September, L&T has completed an impressive 212 km of the Bullet Train Corridor out the 468.24 km that it is responsible for. If you are travelling on the Mumbai-Ahmedabad Highway, you can catch a glimpse of the completed stretches running parallel to or crossing over the road from Navsari onwards.

 

Besides this, L&T’s Transportation Infrastructure vertical has not only imported the entire consignment of specially-made rails and fasteners from Japan, but it has also started laying the rails on a stretch close to Vadodara city.

 

As regards the 7 stations in L&T’s scope, work is at an advanced stage for Anand, Bharuch, Surat, Vapi and Bilimora. While the structural work has already been completed, L&T’s Buildings & Factories vertical is now carrying out the remainder of the tasks in fast-track mode.

 

Each of the Bullet Train stations manifests a specific theme that NHSRCL has chosen. For instance, the theme for Anand station is milk drops; the theme for Surat station is diamonds.

 

L&T’s target is to hand over the majority portion of the Bullet Train Corridor under its scope, including the stations, by December 2025.

 

“In fact, in March this year, we handed over a 32-km stretch (on the Surat- Bilimora section) to another agency which is responsible for laying the tracks there,” says Project Director V V Ramana Murty of L&T’s Heavy Civil Infrastructure. Surat-Bilimora is the priority stretch that NHSRCL plans to throw open in 2026.

 

India’s biggest-ever infrastructure project has already built itself a head of steam and powering it forward is a suite of tech-driven solutions that the execution teams have adopted. This exemplifies L&T’s commitment to innovation and excellence in critical infrastructure development.

 

While we are enmeshed in chasing the travails of daily life, the train tracks of India’s future are shaping up – faster than we think, and L&T is making that possible.