Age: 16 years

Status: A committee of engineers has recommended the flyover’s demolition within five years. The panel has identified structural defects and also pointed out that the flyover does not help ensure smooth flow of traffic. The committee has suggested retrofitting to make the flyover safe for another five years.

Built by: Calcutta Metropolitan Development Authority and Tantia Constructions

A concrete flyover has a life span of at least 50 years and can last longer if properly maintained.

But in Calcutta, a flyover that is less than 20 years old is in such a state that it needs to be pulled down.

Engineers blame the “flawed design” of the Chingrighata flyover, which connects EM Bypass with Sector V and was unveiled in 2004, for its sorry state.

A committee of engineers, which was set up to assess the health of bridges and flyovers in the city following the collapse of the Majerhat flyover in September 2018, has recommended demolition of the Chingrighata flyover.

With some retrofitting, the engineers have suggested, the structure can at best last another five years.

“Two factors were considered by the committee before it concluded that the Chingrighata flyover needed to be pulled d own. Is the flyover’s health good? The answer is ‘no’. Is it serving its purpose by facilitating traffic movement? Again, the answer is ‘no’,” an official of the urban development department said.

The Calcutta Metropolitan Development Authority (CMDA), which reports to the urban development department, is the custodian of the flyover.

A CMDA official said a 2.85m-high barrier was placed right where the flyover starts on the Bypass to ensure only cars and light goods vehicles could use the structure.

“During the health assessment, the committee raised the question whether a flyover that was barely 16 years old should be out of bounds for heavy vehicles such as buses. If buses are not allowed to ply on it, the flyover’s utility comes into question,” the official said.

Several Calcutta flyovers in their teens, 20s and early 30s are in poor condition. A few need retrofitting and health checks have detected serious ailments in some.

Cracks have appeared on piers of the Sealdah flyover and weeds have penetrated deep into the concrete of Bijon Setu. A flank of the EM Bypass-VIP Road flyover had collapsed in 2013 and a crack was spotted in one of the piers last year.

A source, who is privy to the recommendation of the committee of engineers, said: “The report says the (Chingrighata) flyover is structurally weak because of its flawed design. It also says there are problems with the geometrics of the structure. Heavy vehicles find it difficult to manoeuvre the sharp curves of the bridge. If heavy vehicles are allowed on the flyover, they might hit the crash barriers near the sharp curves or even topple over the barriers,” the source said.

“All these factors went against the flyover,” the CMDA official said.

But pulling down the flyover immediately would throw traffic in the area haywire, a reason why the committee suggested retrofitting of the structure to increase its lifespan by five years.

“The committee has recommended demolition within five years. Retrofitting will be done to ensure the flyover remains safe till then,” the CMDA official said.

The CMDA is planning to complete a flyover connecting EM Bypass with New Town. One of its ramps will descend on Sector V.

“The new flyover will benefit commuters headed to Sector V as well as New Town. We will try to ready the flyover before the Chingrighata flyover is demolished,” the official said.