Rail operator MTR Corp reveals 64 sites in Hong Kong being monitored for subsidence
Disclosure comes as government announces new monitoring protocol for stations and facilities affected by ground settlement
Hong Kong’s railway operator, the MTR Corporation, on Monday night revealed the location of 64 of its sites it has been monitoring for subsidence – the sinking of the ground surface – with construction work temporarily halted at three of them after either exceeding or nearing the limits for suspension.
The disclosure by the embattled rail giant, reeling from a series of construction scandals, came as the government announced a new monitoring mechanism for stations and facilities affected by subsidence.
In a statement on Monday night, the MTR Corp listed the 64 sites it was monitoring for subsidence, with the West Rail Line having the most, 15.
Also affected were the Kwun Tong, Tsuen Wan, Island, South Island, Tseung Kwan O, Ma On Shan and Tung Chung lines, Airport Express, East Rail Line and Light Rail.
As previously disclosed, two projects were temporarily suspended because ground settlement had exceeded preset limits, including a property development atop Tai Wai station, where 23mm of subsidence was detected, more than the 20mm limit for triggering a halt.
Another property development at Tin Shui Wai Town Lot No 23 near Tin Wing Light Rail stop was also halted after 90mm of subsidence was detected, more than the limit of 80mm.
At the property development Grand Yoho near Yuen Long station, work was also suspended after sinking of 16mm was found although it did not exceed the 20mm limit.
Of the 64 sites, there was ground settlement at 46. Among them, less than 10mm of settlement was seen in 39, and five had between 10mm and 17mm.
Meanwhile, the government said that foundation works causing settlement in nearby structures was not uncommon but that it would adopt a new monitoring mechanism.
Under the Buildings Ordinance, private developments are required to obtain consent from the Buildings Department and notify it before commencing construction.
With the new mechanism, the department would notify both the Electrical and Mechanical Services Department and the corporation when granting a private project consent to start work within a railway protection area to give the MTR time to formulate plans to monitor operations, a government spokesman said.
In individual cases, if it came to the MTR’s knowledge from other sources that private works had commenced within railway protection areas, it would notify both departments to enhance communication. If subsidence of more than 20mm was detected, the two departments would assess the safety of the sites and inform the public within 48 hours.
The government said that even if subsidence reached the limit of a site, it would not necessarily mean the railway facilities had become unsafe.
The corporation has been beset by scandal following recent revelations about shoddy work and alleged cover-ups during construction at three stations along the HK$97.1 billion (US$12.4 billion) Sha Tin-Central link.