In Bad Shape: Bridge collapses can be easily prevented in India

Observing that “prima facie the municipality has defaulted which led to the unfortunate incident,” the division bench of Chief Justice Aravind Kumar and Justice A J Shastri directed the state to “secure” all files on contracts and agreements related to the bridge and file it before the Registry in a sealed cover by November 17.

.To be sure, there has been a significant drop in the number of bridges collapses in recent years. Yet, India needs to do a lot more to prevent them.

According to data compiled by the National Crime Records Bureau (NCRB), the number of such incidents fell from an average of 45 in 2012 and 2013 to eight in 2021.

The latest Accidental Deaths & Suicides in India report says eight accidental bridge collapses occurred in 2021, compared to nine in 2020.

While the number of such cases recorded each year has varied, the number of such incidents has declined considerably.

Higher than the global average 

Even so, the average number of bridge collapses in India is still a lot higher than the global average, especially considering the number of deaths caused by such incidents.

According to a 2020 study titled Analysis of bridge failures in India from 1977 to 2017, published in the international journal Structure and Infrastructure Engineering, as many as 2,130 bridges -- excluding culverts and pedestrian bridges -- have failed to be of use or collapsed during various phases of construction in the past four decades.

The report also mentions that bridges in India have an average life span of 35 years compared to the global average of 50 years.

India also reported a 25 percent higher mortality rate when compared to most other large countries with more than 10,000 bridges. A 25 percent higher mortality rate means that every bridge collapse in India has a 25 percent higher chance of reporting a loss of life when compared to other countries. China was second on the list.

Moneycontrol has also compiled a list of 12 bridge collapses in India in the last year, based on reports in various news publications from across the country.

This year alone, there have been several bridge collapses, including that of the Dudhsagar Waterfall Bridge in Goa, the Chakki Bridge in Himachal Pradesh, and Sukthwa River Bridge in Madhya Pradesh.

The reasons ranged from poor design and construction material to rushed timelines and lack of maintenance, plus a selection procedure under which a company that submits the lowest bid is declared the winning bidder.

This part of Moneycontrol’s In Bad Shape series looks at some of the reasons behind these incidents.

According to the Indian Bridge Management System (IBMS) report, the country has 172,517 major and minor bridges and culverts on national highways.

Of these, 134,229 are culverts, 32,806 are minor bridges, 3,647 major bridges and 1,835 are extra-long bridges. Around 30 percent of the culverts, 12-15 percent of minor bridges, 8-10 percent major bridges and 5 percent of the extra-long bridges are in “poor condition,” the report said.

What needs to be done? 

Structural engineers Moneycontrol spoke to said that almost 99 percent of these collapses occur due to failures in the construction process.

“The industry is not geared to deal with infrastructure growth at such a fast pace,” one engineer said.

Every structure has a service life. If designed properly and constructed with the specified materials and procedure, a structure should be able to serve its design life. Generally, bridges should last 99 years, buildings 60 years and boundary walls 10 years, say infrastructure experts.

Bridge collapses generally occur on account of scaffolding failure or due to girders shifting from their support base or because poor-quality construction materials were used.

Another reason is the absence of qualified engineers at construction sites, which are mostly in Tier 2 and Tier 3 towns. Supervision of these projects by well-trained personnel is lacking. In short, a lack of proper implementation and monitoring of these projects is held up as the primary reason behind the collapses.

“Some bridges are being constructed in remote areas and there is an acute shortage of experienced and skilled manpower, especially in Tier 2 and Tier 3 cities. There is also no proper manpower available to carry out a regular structural audit of these infrastructure projects,” said Abhay Gupta, structural engineer and owner of Skeleton Consultants Private Limited.

Digitisation, structural monitoring 

Efforts should focus on digitisation of the construction industry, said Gupta. “This means that there should be a greater application of digital platforms such as drone technology, which can be used to monitor inaccessible areas and those pictures can be analysed in laboratories. The pictures can indicate the intensity of cracks and even monitor repairs from the ground,” he said.

Regular structural monitoring of public infrastructure and assessment of residual service life is critical. This means that if a structure is designed for 99 years, it should be checked after 40 years to see if it has a sufficient residual life or if it needs to be replaced, explained Gupta.

The Morbi incident in Gujarat clearly showed the involvement of incompetent personnel in the renovation of old infrastructure. In this case, the municipality was given the task of managing a bridge, something in which it had no expertise.

The local administration should have appointed a consultant who had the expertise to supervise the quality of construction. Small firms winning bids and undertaking complex engineering tasks that require highly skilled manpower can prove problematic,  experts say.

“When small firms participate in such bids, construction quality is bound to be compromised. The contractor selected will have to deliver the project as per the schedule and the rush to complete these projects leads to complications,” said another infrastructure expert, who did not wish to be named. “It starts with the pre-qualification process not being stringent enough and leads to fly-by-night operators entering the highway market. The lowest bidder mechanism ensures that quality and safety get thrown out of the window.”

What is NHAI doing? 

Officials say that the National Highways Authority of India (NHAI) is working on a comprehensive bridge maintenance policy, which may be launched next year.

The policy will include standards of maintenance, lighting, painting, and construction of bridges across India. The new policy will hold construction companies accountable for any wear and tear in bridges and even roads.

Installation of rumble strips, signage boards, and preventing wrong-side driving on one-way bridges are some of the measures that have been planned to improve safety on bridges.

The Authority is currently carrying out audits across 13 states including Bihar, Uttar Pradesh, Karnataka, Maharashtra, Madhya Pradesh, West Bengal, Kerala and Tamil Nadu.

The NHAI plans to put in place a comprehensive plan by next year based on the audits. It is also working with international organisations to address problems related to bridge construction and maintenance in India and has sent teams to Singapore, the Netherlands, and Germany.

Officials say the Authority has also begun working with states sharing borders with Delhi to install strong crash barriers by replacing old railings at all bridges on national highways.

The project will be launched across the country if the pilot to prevent vehicles from rolling over the barrier and plunging is successful.

In the case of collisions, scientifically proven crash barriers with special designs will help in preventing the fall of speeding vehicles, preventing the loss of lives, they said.