The State Council for Assessment and Acceptance of Construction Works has raised technical warnings over some bidding packages for the Hanoi metro project.

The 12.5km route is planned to run from the Nhon area, in Tu Liem District, to the Hanoi Station in Dong Da District.

A metro line in Hanoi

However, according to the council, the design of the overground section running from Nhon to the Daewoo Hotel, (in Bidding Package No. 1) will not only be an alleviation to the city's traffic problem, but would also be unsustainable.

“In order to protect the integrity of the urban space all lines should be built underground," the council insisted. They cited the 1995 earthquake in Kobe, Japan as a warning for careful design. Since Hanoi sits upon a fault line that is susceptible to earthquakes measuring up to 7 on the Richter Scale, the station linking Nhon and Hanoi may be vulnerable, they said.

Bid No. 2, proposes to narrow neighboring streets to build stations S6 and S7, which might pose additional street traffic problems. According to this plan, pedestrians would have to pass through the terminals in order to cross the street. They added that the climate of Hanoi is not conducive to the proposed stations.

Out of nine bidding packages, 1, 2, 4 and 5 have already been approved.

The council has asked that the investors review and revise their designs, especially those problems related to seismic issues.

The Nhon-Hanoi Station metro project, with a total investment of VND18.4 trillion (USD876.2 million), was begun in 2010 and was slated for operation in 2016.

According to the current plans for transportation development into 2020, a master plan through 2030 and a vision towards 2050, Hanoi should have eight operational rail lines.