Experts say lightning strike ‘highly unlikely’ to have caused Genoa bridge disaster as state of emergency is announced.

Rome, Italy – As the search for survivors in Genoa continues, questions are being raised about whether the collapse of the Morandi bridge – one of the main arteries into the city – could have been prevented.

On August 14, at around 12pm local time (10:00 GMT), the central section of the bridge gave way as Italy experienced a gust of bad weather. So far, 39 people have been confirmed dead, while 12 of the wounded are in critical condition.

On Wednesday, Prime Minister Giuseppe Conte declared a 12-month state of emergency for the northwestern city of Genoa and promised five million euros ($5.7m) to the rescue efforts.

Hundreds of people have been evacuated from homes located near the two remaining sections of the bridge for fear they too would collapse. The bridge is to be demolished and an investigation has been opened against unknown persons as the causes of the collapse are yet to be established.

The 1,182-metre structure, known as Italy’s “Brooklyn Bridge”, was designed by the architect Riccardo Morandi. It was inaugurated in 1967 and went through major reinforcement work in the 1990s.

Transport minister Danilo Toninelli and co-deputy Prime Minister Luigi di Maio called for managers of Autostrade per l’italia – which runs Italy’s toll highways network and is part of the company Atlantia – to resign. Toninelli also threatened to revoke the company’s managing license.

“It is the company that holds the license who is responsible for maintenance and safety. If a bridge like this one collapsed it means this maintenance hasn’t been carried out,” Toninelli said.

{articleGUID}

Autostrade per l’italia said that routine reinforcement work had been ongoing involving the bridge’s foundations. The structure was being “constantly monitored with highly specialised technology,” a statement said.

“The bridge is subject to constant monitoring, even beyond the quarterly inspections prescribed by law,” said Stefano Marigliani, director of the Genoa section of the network, in a radio interview. “It was absolutely monitored, we didn’t have any reason for concern.”

“We have heard a number of hypotheses, not least this exceptional event of the lightning. We will have to assess what could have happened,” Marigliani continued.

Italian news agency Ansa quoted a bystander, Pietro M, as saying he saw “lightning strike the bridge” just before the collapse.

A structure at risk

Experts told Al Jazeera that the possibility that lightning caused the collapse couldn’t be written off, but was highly unlikely.

“For a collapse of this type, the most likely hypothesis is that one of the stay-cables, those inclined elements linking the pillar’s summit to the horizontal structure, gave in,” Gianni Royer Carfagni, who teaches a course in bridge construction at Parma University’s engineering and architecture department, told Al Jazeera. “The failure of one of the stays can produce a domino effect.”

Daniele Zonta, a civil and environmental engineering professor at the University of Strathclyde, Scotland, also said that the deterioration of the bridge’s concrete tendons had long been a cause for concern and study.

“Its state of deterioration was notorious, to the point that the bridge is typically used as a handbook example in Italian structural engineering classes,” Zonta said. “Exactly for this reason, the bridge was supposedly well maintained and continuously supervised.”

Experts say the bridge needed constant maintenance works almost since it was first constructed [Stefano Rellandini/Reuters]

Ansa cited a 2011 report by Autostrade per l’italia as saying the bridge had been suffering from decay due to high traffic.

Two years ago, Italian structural engineer and lecturer at Genoa University, Antonio Brencich had warned in an interview with an engineering website that the bridge’s design was problematic.

“Ever since the first decades [of its lifespan], the bridge has been subject to major maintenance works,” he said, “with continuous costs from which we can foresee that in a few years, maintenance costs will have exceeded reconstruction costs.”

Il Sore 24 Ore, Italy’s financial newspaper, reported that Autostrade per l’italia had launched a 20,000-euro ($22,770) call for tenders in April 2018 for “structural retrofitting” of the bridge, which would have included work on the collapsed section.

“Stays on the eastern span of the bridge had been remade, with huge costs,” said Royer Carfagni, the Parma University lecturer, “But it was thought that the problem was not critical on the western span, which is the one that collapsed.”

A decade of discussions

But the state of the bridge had been under discussion for more than a decade.

According to newspaper reports dating back to 2006, the government and highways company had considered demolishing and rebuilding the structure as part of a project to build the “gronda” highway bypass.

Planners wanted to alleviate traffic on the Morandi viaduct, which saw 25 million vehicles transit through it each year – almost one a second.

However, the project was highly contested and a public debate took place in 12 meetings between February and April 2009.

Five options to ease traffic were presented to citizens, but grassroots committees opposed them over concerns about costs as well as the impact on the environment and local residents.

{articleGUID}

The debate continued and in December 2012, it was brought up in a public hearing of the Genoa City Council.

Giovanni Calvini, the local president of the Confindustria, the general confederation of Italian industry, said in interview earlier that month: “When, in 10 years, the Morandi bridge will collapse, and all of us will have to be stuck in traffic for hours, we will remember the names of those who now say ‘no’ [to the expansion].”

Councillor Paolo Putti of the now-governing Five Star Movement criticised Calvini’s comment.

In an April 2013 press release, a Five Star Movement citizen’s committee, which was among those against the work, referred to the potential collapse of the Morandi bridge as a “fairy tale”. A screenshot of the page, which now appears to have been removed, was widely shared online since the collapse.

“If Autostrade per l’italia [at the time] said everything was in order, that is a problem,” said Luigi di Maio, head of the Five Star Movement and Italy’s co-deputy prime minister, in an interview with Italian newspaper La Repubblica on Thursday. “Let’s avoid playing with this event in order to blame the Five Star Movement.”

The gronda highway bypass was eventually approved by Italy’s former transport minister in September 2017.

Five collapsed bridges in five years

The Morandi bridge collapse is the latest in a series of similar incidents – at least five in the past five years.

On April 18, 2017, a viaduct collapsed along a bypass road near Fossano in the northwestern region of Piedmont, narrowly missing a police car under the bridge. The bridge had been built in the 1990s by a government-owned company.

Another bridge came down on the A14 highway near Ancona on March 9, 2017, a stretch of road also controlled by Autostrade per l’italia. Two people were killed and another two injured.

Firefighters and rescue workers are still clearing the rubble from Tuesday’s collapse [Stefano Rellandini/Reuters]

On October 29, 2016, an overpass bridge fell on a motorway in Annone Brianza, in the northern region of Lombardy, just as a truck was crossing it, killing one and injuring five.

While on October 22, 2013, a bridge collapsed during heavy rains in Liguria, the same region that hosted the Morandi bridge, killing two.

Royer Carfagni said these collapses had different structural causes but were “still linked to the fact that construction was made using old design techniques, and to the possibility of corrosion problems.”

“We need to find out how extensive inspections were. If just superficial, then the maintenance would be superficial as well,” professor Muhammed Basheer, head of the civil engineering school at the University of Leeds in the UK, told Al Jazeera. “The possibility of missing potential causes of deterioration might have contributed to the failure.”