Design flaw on Mumbai Metro 7A could cost Rs 260 crore, delay airport link

A height clearance lapse on Mumbai Metro Line 7A has put a completed viaduct stretch under scrutiny near the airport. If no relaxation is granted, the Mumbai Metropolitan Region Development Authority may have to rebuild nearly a kilometre at a heavy cost.

In Short

• Nearly 1 km viaduct near Airport Colony may need demolition and rebuild
• MMRDA blames consultant for not factoring height in design
• Delay likely as MMRDA awaits Airports Authority's final report

A design and planning lapse on Mumbai Metro Line 7A could leave the Mumbai Metropolitan Region Development Authority (MMRDA) facing a Rs 250-260 crore loss, with nearly a kilometre of an already constructed viaduct potentially needing to be demolished and rebuilt.

The problem has emerged near the Airport Colony station in Vile Parle East, where the elevated metro infrastructure falls within the critical air funnel of Chhatrapati Shivaji Maharaj International Airport.

The viaduct and its overhead electrification (OHE) system are now facing scrutiny over their height.

According to the MMRDA, the additional height required for the OHE system was not adequately accounted for during the design and planning stage.

As a result, the infrastructure is understood to be around 2.5 metres above the clearance permitted under aviation restrictions.

The issue was detected when work was already at an advanced stage in 2025. Construction on the affected stretch has remained halted since then, while the MMRDA has sought a relaxation from the Airports Authority of India (AAI).

However, if the requested relaxation is not granted, the authority could be forced to dismantle and reconstruct nearly a kilometre of the elevated viaduct.

Simply lowering the existing structure may not be feasible because it could interfere with the gradients required for safe metro operations.

In a statement, the MMRDA placed responsibility for the lapse on its general consultant, the Systra-CEG-SMCIPL consortium, saying it was tasked with coordinating design and statutory requirements, including aviation-related restrictions.

“The additional height required for the OHE system was not adequately highlighted and factored in by the Consultant at the appropriate stage of design and planning,” said Basavaraj MB, Director, Metro Projects.

The MMRDA said it is currently pursuing the matter with the AAI and awaiting its final technical report on the applicable height clearances and possible modifications.

A comprehensive technical assessment will be undertaken once the report is received, it said.

The potential setback comes as Metro 7A itself has already faced delays.

The 3.4-km corridor, planned to connect Andheri East with Mumbai airport and provide connectivity to the underground Metro Line 3, was originally scheduled for completion in 2021.

With the airport link already several years behind schedule, any decision to rebuild the affected viaduct could mean another delay—and a potentially hefty bill for infrastructure that has already been constructed.

- Ends