MTR Halts Unapproved Tung Chung West Column Repairs as Government Sets November 16 Report Deadline

Column repairs stopped as investigation widens

Hong Kong's Highways Department has required MTR to submit a detailed investigation report by November 16, 2026, after the railway operator discovered unapproved repairs to concrete columns at the Tung Chung West Station construction site. The department says the Tung Chung Line Extension's target of opening in 2029 remains unchanged.

MTR said a routine inspection in October found that material had been used to fill the upper ends of some columns on the platform level without its prior approval. It immediately ordered the main contractor, the Bouygues-Dragages joint venture, to stop the repair process and began examining columns and construction procedures across both the platform and concourse levels.

The operator says the situation does not involve structural safety. Its investigation follows allegations that about 30 columns on the concourse level have gaps of roughly 20 to 30 centimetres between their concrete tops and the underside of the floor above, with steel reinforcement exposed.

MTR's confirmation concerns unapproved repairs on the platform level, while the allegations about roughly 30 columns concern the concourse. The operator has not confirmed that number or directly answered whether the concourse columns were poured short of the floor above. The investigation therefore covers both where problems occurred and how work was carried out.

What the reported gaps look like

Photographs described in the reporting show four columns about eight to nine metres tall, each with a cross section of roughly half a metre by half a metre. Two appear to have concrete reaching the top, while the other two show spaces beneath the floor above.

The concourse reportedly contains about 60 columns, with approximately 30 said to show similar gaps. On those figures, the allegation concerns about half the columns on that level. MTR has described the confirmed discovery as involving some platform columns, without publishing a total.

Steel bars are reportedly visible within the gaps. These bars are reinforcement, the steel placed inside concrete to help the finished structure carry forces. The concern raised by the photographs is whether each column has been completed so that it can carry the weight assigned to it in the design.

The distinction between unfinished construction and completed work is central to the investigation. MTR said it found the unapproved filling process while inspecting work that was still unfinished. Its subsequent review extends to completed columns and the procedures used to build them.

What happened between October and November 16?

MTR's inspection and the government's response took place over several weeks. The Highways Department received formal notification on November 2, then conducted site checks and met the operator before setting the deadline for a detailed report.

• 2023: Construction of Tung Chung West Station began.
• October 2026: MTR discovered unapproved filling repairs during a routine inspection of unfinished work.
• October 2026: The Highways Department separately inspected concourse areas, mainly examining columns where concrete pouring had not yet begun.
• November 2: MTR notified the Highways Department of column construction quality problems and attempted repairs using an unapproved method.
• November 3 and 4: Highways Department personnel visited the site to check the situation.
• November 6: The department met MTR to discuss the incident and investigation progress.
• November 16: MTR must submit its detailed investigation report, two weeks after notification.

The department has also instructed MTR to press the contractor to prepare a detailed repair plan and carry out the necessary work at its own expense. It wants measures to protect the wider construction schedule while bringing the work up to the required standard.

Why the connection above a column matters

Ho Wing-ip, a senior electrical and building services engineer, explained that a column's ability to support the structure depends on how its concrete and reinforcement connect with the floor slab above. A slab is the broad structural layer that forms a floor.

Concrete is particularly useful for resisting compression, the squeezing force created by weight pressing down. If its top stops short of the slab, the intended route for carrying that weight through the column may be incomplete. Ho estimated that, where only reinforcement reaches the slab, the column's bearing capacity could fall below 10% of its design capacity.

Ho said that if the reinforcement also fails to engage the slab, the column would be unable to perform its designed supporting function. His assessment depended on the actual condition of the connection, the number of affected columns and the weight already built above them.

Ho explained that uncertainty in comments translated from Cantonese:

Without the total weight of the building above the floor slab, and without knowing how many columns lack concrete, an accurate figure cannot be given. I personally think it should not involve an engineering danger.

MTR's stated position is that structural safety is not involved. Ho likewise said the stage reached by construction above the columns matters when assessing immediate danger. The investigation will need to examine the physical condition of the columns alongside the loads they currently carry.

Investigators must trace drawings and site decisions

Ho identified several possible explanations that investigators should examine: dimensions missing from design drawings, dimensions misunderstood or shortened during construction, or some work being carried out using an older drawing. He presented these as possibilities requiring investigation.

His suggested checks reach beyond measuring the visible gap. Investigators would need to compare the intended dimensions with what was built, identify the drawings used and establish which workers and supervisors were responsible for each stage.

MTR is reviewing construction procedures as well as the columns themselves. That puts two issues within the investigation: how the original work was carried out, and how a subsequent attempt to fill the column tops proceeded without the required approval.

The operator says it has strict quality assurance procedures for railway projects. The Highways Department has separately committed to reviewing site supervision and quality acceptance processes, including how construction is checked before it is accepted.

What must happen before repairs can restart?

The Bouygues-Dragages joint venture must give MTR a comprehensive report and propose corrective work. The stopped process can resume only after the plan receives MTR's approval and every other approval required for that work.

MTR says all corrective work must meet the relevant statutory requirements before final acceptance. The contractor will bear the associated costs. The Highways Department has also called for repairs to proceed promptly once the necessary arrangements are in place.

Ho said filling the gaps with concrete and then measuring the columns' hardness could provide a remedy. He also raised the need to check whether newly placed concrete would achieve the strength required by the design. His suggestion remains subject to the investigation and an approved repair method.

MTR has not announced a date for restarting the stopped repairs or published the final engineering solution. The stop instruction applies to the relevant repair process. The operator's description does not announce a shutdown of the entire station construction project.

Who is responsible for checking the work?

MTR is developing the Tung Chung Line Extension under an ownership model, making it responsible for the project's design, construction, operation and maintenance. Under the project agreement, its construction responsibilities include engineering management and site supervision.

The Highways Department monitors progress, safety and quality through site visits and checks of key construction processes. It says it uses a risk based approach, directing inspection attention according to the risks associated with particular work.

The department's previous October inspection at Tung Chung West covered concourse areas and mainly involved columns where concrete pouring had not started. The construction stage examined during that visit matters because the current allegations concern gaps left after concrete had been poured.

The department says it will review supervision and acceptance procedures and stay in close contact with the Buildings Department and other relevant bodies over the repairs. MTR must manage the contractor's response while the government follows up on compliance, quality and structural safety.

Does the incident change the opening timetable?

The Highways Department says the Tung Chung Line Extension is still targeted to open in 2029. The project has a budget of about HK$19.5 billion, and the main structure of Tung Chung West Station is scheduled for completion in the first half of 2027.

The station is being built using a method that proceeds from upper structural levels downwards. Construction began in 2023. The department has asked MTR to take measures so that investigation and repair work do not disrupt the extension's wider programme.

The November 16 report is the next stated deadline. It should provide the department with a detailed account of the incident, while the contractor's repair proposal must pass the required approval process before the stopped work resumes.

For future passengers, the announced opening target remains the same. For the construction team, the immediate task is more specific: establish the extent and cause of the column problems, agree a compliant repair method, complete the work at the contractor's expense and obtain acceptance.

Key Points

• MTR stopped unapproved filling repairs at the tops of some platform columns at Tung Chung West Station.
• About 30 of roughly 60 concourse columns reportedly have gaps of 20 to 30 centimetres; MTR has not confirmed that total.
• MTR says the situation does not involve structural safety.
• The Highways Department requires a detailed investigation report by November 16, 2026.
• The contractor must pay for corrective work and secure the required approvals before the stopped repairs resume.
• The Tung Chung Line Extension's target opening year remains 2029.