The poor engineering, rush and construction materials used in the Vivekananda Road flyover project are being blamed for the Thursday's tragedy that killed 24 people even as the death toll is feared to go up.
The construction of the flyover which first began in 2009, during CPM regime, has missed nine deadlines so far. However, last November Chief Minister Mamata Banerjee committed herself to opening of the long-delayed flyover by February 2016, which clearly did not happen.
Seemingly under the obligation to make good on its word, the Trinamool Congress government expedited the construction process to throw open the flyover for commuters before elections.
A portion of the flyover came down crashing on hundreds of pedestrians and commuters on Thursday in the busy Burrabazar area, just hours after workers had finished concretising the ill-fated portion.
"There can be many reasons for the collapse of a under construction flyover. It seems there may be some problems related to stability. There may be insufficient steel girders used or faulty placement of steel girder could have led to this collapse," Arup Guha Niyogi, a professor at Jadavpur University's civil engineering department, said.
Niyogi who specialises in structural and bridge engineering, also said there might be some defects in design and construction.
"Since the concretisation was done yesterday (Wednesday), the concrete remains in a weak state in which it has weight but has not acted as the load-bearing structure," he said.
The delay in project is also being blamed as another contributing factor to the tragedy.
Shocked at the incident, Indian Institute of Technology-Kharagpur (IIT-Kgp) architecture faculty Joy Sen, who is "very familiar" with the heavily-congested area, said such large-scale projects are executed in phases and if time is not taken into consideration, then it becomes risky.
"Phasing of construction and time and use of materials are interlocked. If these things are not done on time, then construction like these which are exposed to weather becomes very risky.
"They have a time schedule and you cannot delay with these projects. You need proper planning and you can't play with human lives," Sen, a professor and head of architecture & regional planning department at Ranbir and Chitra Gupta School of Infrastructure Design and Management, IIT-Kgp said.
'Act of God'
The Hyderabad-based contractor, IVRCL is now under a high-level investigation ordered by the West Bengal government. A case against the contractor has been made under sections 304, 308 and 407 of the Indian Penal Code and a local office of the company has been sealed.
A spokesperson of the construction company in question drew flak after he blamed 'God' for the tragedy.
"It is nothing but God's act," said Panduranga Rao of .
"IVRCL grieves the loss of precious lives and injuries to people and will cooperate with the authorities in investigating this accident," the IVRCL said in another statement.
“The Vivekananada Flyover project in Kolkata under execution by IVRCLJ has suffered an accident caused by an under construction section falling down,” it said.
"All necessary process and quality steps have been taken as per standard operating procedure and after obtaining all clearances. The collapsed section is the 60th," it said adding that in the Vivekananda Flyover project 59 sections with a total length of about 0.9 km have been completed so far.
Meanwhile, IVRCLJ, which has operations across the country, has a very troubled track record. The Andhra government in 2009 was considering blacklisting the said company based on the recommendations made by the state labour department. The Uttar Pradesh Jal Nigam, in 2011, blacklisted IVRCLJ along with another company for using sub-standard materials in drinking water and sewage projects.
The then CPM government in 2008 awarded the contract to IVRCLJ to construct the 150-meter stretch Vivekananda Road flyover at a cost of Rs 164 crore, which was sanctioned under the JNNURM scheme.
Toll likely to go up
About 88 people have been injured in the incident, with many in critical conduction at hospitals. The rescue operation involving five columns of Army personnel (about 300 in number) along with NDRF, state disaster management, city police and fire brigade personnel is underway.
Authorities fear that the death toll is likely to climb up as many are still suspected to be trapped under debris.
West Bengal Governor K. N .Tripathi, who visited the spot, sought a report of the incident from the state government.
The government, meanwhile, has announced an ex-gratia compensation of Rs 5 lakh to families of dead and Rs 2 lakh to gravely injured people and Rs 1 lakh for those who suffered minor injuries.
(With input from Agencies)