The dispute over whether to have an elevated Metro station at the airport or an underground one has resurfaced, putting a question mark on the plan to provide seamless connectivity to fliers.

The stalemate between the airport and Metro Railway authorities on the type of airport station on the proposed Noapara-Barasat Metro link had apparently been resolved six months ago.

“The Metro authorities had then agreed to build the airport station underground but they now want to revise the plan. They want elevated tracks around the airport,” said V.N. Agrawal, chairman, Airports Authority of India (AAI).

“We have to incur extra expenditure of around Rs 500 crore to Rs 550 crore if the station is underground. We will take the station underground only if there is no alternative,” said P.B. Murthy, general manager, Metro Railway, Calcutta.

“For the extra funds, we will have to approach the Railway Board,” he added.

Applying for funds to the Railway Board could delay the project by months. If the board declines to provide funds, the project itself might be in jeopardy.

The Metro authorities told senior AAI officials that they wanted to change the plan at a meeting in Delhi a fortnight ago.

The new integrated terminal building at the airport is set to open by June.

AAI officials said they did not have any problem with the tracks being elevated on the airport premises. “Our objection is to the elevated tracks at the entry and exit points, which is what the Metro authorities want,” said Agrawal.

“The elevated tracks are likely to be within the approach funnel of the runway, which can jeopardise flight movement,” said a senior airport official.

The approach funnel is the area in and around the airport where construction cannot be allowed for the safety of flights.

When the Rs 2,900 crore, 18km Metro link was conceived, the authorities had planned to use Eastern Railway’s existing suburban track to the airport and build a parallel track for double-line operation. It was later decided that the tracks would go underground around 2km from the airport and the station would also be underground.

“If there are no technical difficulties in the revised plan, we can allow them to build an elevated station. Whether underground or elevated, the station will be opposite the existing domestic terminal building,” said an airport official.

Airport authorities plan to install walkalators and elevators for the convenience of fliers. The proposed station will be connected with the integrated terminal’s Level 1 basement by a walkalator. If the plan translates into reality, passengers will need less than 10 minutes to reach the check-in counters from the airport station.

Another Metro link to the airport from Garia, a Rs 3,951 crore project, is being built. The tracks are supposed to be underground.