Namma Metro In Bengaluru Puts A Spoke In The Infrastructure Wheel

On Jan. 10, a metro pillar collapsed in Bengaluru’s HBR Layout killing a mother and her toddler. At 10:45 a.m., a preliminary report of the police suggested that the reinforcement cage of the metro pier, which was under-construction, buckled. 

As Bengaluru was grappling with questions on safety of 15 million residents with Namma Metro standing tall as a critical mobility pillar, a part of Brigade Road caved in, injuring a biker on the afternoon of Jan. 12.

In the case of the metro pillar collapse, fingers pointed to breakage of the supporting wire failing to hold the pillar in place. Bengaluru Metro Rail Corp. Ltd. blamed a private firm Nagarjuna Construction Co.—in charge of the metro construction—for the tragedy.

The 3-metre-deep sinkhole on Brigade Road appeared close to a 2.762-km metro line, which is being constructed right under. This time, the BMRCL said that water leakage from an underground pipeline caused the sinkhole, and blamed Bengaluru Water Supply and Sewerage Board. 

On Jan. 17, another sinkhole appeared on Mahalakshmi Layout main road near the Sapthagiri Convention Centre.

“We never compromise on safety and quality. We use high-end materials—be it cement or steel. There is no compromise. We believe in delivering consistent quality,” said Anjum Parvez, managing director at BMRCL. 

However, this incident has been a wake-up call for Namma Metro, which has completed over 10 years of service in the city, starting with the first phase in 2007 between Baiyyappanahalli and Mahatma Gandhi Road.

“We are determined to find the exact cause of the pillar collapse and provide additional safety standards. In fact, we have suspended work on piers above 12 metres on this corridor till we come up with updated safety measures,” Parvez said. 

Some pillars of the metro line are as high as 15m-22m on this corridor. The pillar that collapsed was 18m tall.

The engineers from both BMRCL as well as the contractor check the work at every stage and work on the next stage is carried out only after approval, a BMRCL staff said, speaking on condition of anonymity.

“We have not only constituted an internal committee to inquire into this incident, but have also asked the Indian Institute of Science to conduct a detailed probe and submit a report,” said Yashavant Chavan, spokesperson of BMRCL. 

That apart, a show-cause notice has been issued to NCC, and the response is awaited, continued Chavan. 

Karnataka Home Minister Araga Jnanendra named the accused persons listed in the FIR. NCC is named A1. NCC officials named A2, A3, A4, A5 and A6 are Junior Engineer Prabhakar, Director Chaitanya, Special Project Manager Mathai, Project Manager Vikas Singh and Supervisor Lakshmipathi. A7 and A8 are BMRCL officials—Deputy Chief Engineer Venkatesh Shetty and Executive Engineer Bendekari.  

Media was quick to question why the chief engineers of BMRCL weren’t named in the FIR. “It is the responsibility of the entire organisation called BMRCL. One must remember that at the time of the incident, site engineers were on the spot taking care of the project. Let us wait till the inquiry report is out,” said Chavan. 

Deputy Commissioner of Police (East) Bheemashankar S Guled requested a team of professors from IIT-Hyderabad to probe the incident.

According to police persons in the know, who spoke on condition of anonymity, BMRCL has earlier roped in IISc experts to conduct studies for various projects of theirs. They decided to seek IIT-Hyderabad’s help to make sure we have an unbiased report, a person mentioned above said.

A team of professors from the institute inspected the spot on Jan. 13, noted down the details, and visited other construction sites of Namma Metro. They took measurements and collected samples for further investigation. The police confirmed that action will be taken once the report is submitted, which is expected in a week.

On the same day, the Karnataka High Court instructed the Registrar to take up this case suo moto and file a writ petition based on media reports.

It is difficult to pinpoint the exact reason though the BMRCL has earlier worked with cages that were heavier and taller, according to a person with knowledge of the matter, who spoke on condition of anonymity. 

The reinforcement cage is supported by metal ropes, also called guy wires. While tying the guy wires to support the cage weighing 30-40 tonnes, one of them reportedly gave way, and the whole structure made of iron bars fell over, according to a BMRCL staff, who is aware of the matter.

Professor JM Chandra Kishen from the department of civil engineering at IISc has examined the materials and investigated the accident site. He has also gathered information from the labourers and the site engineers.

“We are talking about the reinforcement cage that has collapsed. One needs to understand that it is a pillar only after it is concreted. Now, this structure is 18m in height, which is akin to a six-storeyed building. Now, you can imagine the weight of this structure. That’s why you will need a supporting structure in the form of guy wires," said Prof. Kishen.

"Now, these guy wires are tied at different heights and the other end is tied to a concrete block at the bottom. Here, there is space restriction in the form of roads and barricades. Thus, the height and geometry of the guy wires play an important role.”

The professor has collected earlier pictures of the structure to make a comparative study. As far as the materials are concerned, there has been no problem, he said, based on his study. 

“There is a process called shuttering that is done where a steel box is placed and concreted to support the reinforcement cage. The time taken between placing the reinforcement cage and shuttering should also be probed,” said Prof. Kishen, insisting on training programmes that need to be held regularly for the engineers to maintain safety measures.

The IISc report will be submitted to the BMRCL by Jan. 21. 

According to media reports, a similar incident was witnessed in 2009 where a reinforcement cage fell through injuring two metro workers. “This shows absolute disregard for human lives. Such mishaps can be attributed to timeline issues and lack of accountability,” said Civic Evangelist V Ravichandar.

In October 2020, metro tunneling reportedly caused a part of Sultanji Gunta Road near Bamboo Bazaar to cave in. Similarly in 2021, a portion of Tannery Road caved in for the same reason. In 2021 again, several labourers had a close shave when a heavy crane collapsed from a height of 40 feet. They were working on the stretch between Silk Board and KR Puram. 

The Karnataka State Contractors' Association recently alleged that they are forced to pay bribes to ministers and BJP MLAs. 

BMRCL maintained that tenders are awarded to companies that follow the Corporation's safety guide. “When a contractor is awarded a project, they start work and leave it incomplete for there is no timeline maintained. It’s almost like the contractor has staked a claim on the project and there is no turning back. Moreover, with these bribe allegations doing the rounds, the authorities are perhaps unable to pull up these contractors,” said Ravichandar.

Karnataka Chief Minister Basavaraj Bommai earlier announced that the airport line would be ready by “December 2023”. The accident took place on the 38.44-km KR Puram-Airport metro line under Phase 2B.

If the report finds NCC guilty, BMRCL will be under pressure to find a new contractor and maintain the promised deadline. “The solution lies in demanding timely reports and penalising them if deadlines aren’t maintained,” said Ravichandar.

When a contract has been awarded to a company, they can be fined Rs 5 lakh for a fatal incident and Rs 10 lakh for the second incident.

Can a company like NCC get away with meagre fines?

NCC is a Hyderabad-based private company known for its housing and development projects across India. BMRCL has awarded contracts worth Rs 2,170 crore to this company. 

According to BMRCL, in 2021, NCC Ltd. bagged Metro Rail contracts worth Rs 2,170 crore. The construction plan of Phase 2 has been segregated into three packages.

Metro stations Kasturi Nagar, Horamavu, HRBR Layout, Kalyan Nagar, HBR, Nagawara, Veerannapalya, and Kempapura fall in the first package. Five metro stations: Hebbal, Kodigehalli, Jakkur Cross, Yelahanka, and Bagalur come second. And the third includes Bettahalasuru and Doddajala.

NCC Urban, a subsidiary of NCC Ltd. has announced an annual turnover of over Rs 12,000 crore on its website.

NCC has remained tightlipped, and has refused to comment despite several attempts.

The presence of water at the sinkhole gave rise to many theories. One blamed the metro tunneling to have given rise to pressure and soil movement. Another is the possibility of a damaged water pipeline. 

As far as the sinkhole on Brigade Road is concerned, BMRCL washed its hands of it. “Metro tunneling is done at a depth of 35 feet after completing a survey analysing the strength of the area. It is done through hard rock and it would never touch the soil,” said Parvez.

With 7.5 metres of granite rock below the road surface, the tunnel boring machine passed through 10.5 metres below without applying pressure, according to a BMRCL staff, who spoke on condition of anonymity. 

Assistant Chief Engineer of BWSSB, Kumar Naik confirmed the presence of an old pipeline bypassing the location of the sinkhole by at least 100 metres.

“The pipeline is around 25 years old. But there is no damage. If there was water leaking through the pipe, we would have known this quite some time ago. We would have received complaints from several households too,” he said.

Soil testing done below the road surface pointed to 5 metres of slightly loose soil and the next 3 metres of hard soil. A sanitary pipe that’s not connected to the sewer, could also cause this, said a BWSSB staff, who spoke on condition of anonymity.

While the blame game continues, workers have closed the sinkhole with concrete and vehicle movement has resumed.

The 2.762-km metro line from Rashtriya Military School (Vellara Junction) to Shivajinagar runs underground. This stretch connects with the 21.386-km line from Kalena Agrahara on Bannerghatta Road to Nagawara.

BMRCL uses the services of L&T Ltd. as the contractor, which has deployed two TBMs—TBM Avni from MG Road to Vellara Junction and TBM Lavi from MG Road to Vellara Junction. Out of 1,134 metres that is supposed to be tunneled, the TBMs completed 599 metres, as of November 2022.