Thomson Road building next to upcoming North-South Corridor tunnel to be demolished for safety reasons

The safety concerns came to light after LTA conducted detailed tests to check the strength of the building's concrete. ST PHOTO: YONG LI XUAN

SINGAPORE - A four-storey building in Thomson Road will be demolished to allow excavation works for an upcoming North-South Corridor (NSC) tunnel just metres away to begin safely.

This is after the authorities found that the 57-year-old mixed-use building at 68 to 74 Thomson Road was not strong enough to withstand excavation works.

Instead, the building and the 776 sq m plot of freehold land it sits on was acquired by the Singapore Land Authority (SLA) on Friday (April 16).

The owners of the 12 residential units and four commercial units on the ground floor will have to return their units to the SLA by the end of July and the building will be demolished by the end of this year.

Of the 16 units in the building, 14 had been leased out to tenants.

The unit owners will be compensated based on the market value at the time of the acquisition. SLA and the Land Transport Authority (LTA) said they will work closely with the owners and assist them through the acquisition process.

According to a joint statement by SLA, LTA and the Building and Construction Authority (BCA), the building's foundation required strengthening, but its concrete strength was not strong enough to allow for this.

LTA-appointed engineers had done an impact assessment last year ahead of NSC excavation works, and found that the building's foundation was not uniform.

This was because part of the building was propped up with piles following the demolition of an adjacent building in 1994.

The engineers found that the foundation needed to be strengthened so it could withstand the impact of the NSC tunnel excavation works.

To ensure safety during the foundation strengthening works, all of the building's occupants were moved out in February and had found alternative places to live and do business.

LTA then conducted further tests, which involved taking core samples from the building's concrete, for due diligence. Such tests are invasive and could only have been done once the building was vacated, the authorities said.

The tests found that the concrete was weaker than expected and it would be risky to carry out the foundation strengthening works.

BCA had also conducted an independent inspection of the building in February and agreed with the assessment that while the building was safe if there were no major construction works in the vicinity, it would be impractical and risky to carry out the strengthening works.

The building, which previously housed shops such as a Tanjong Rhu Pau outlet and Animal Infirmary, a veterinary clinic, is the only building near the 21.5km NSC that has been assessed as requiring foundation strengthening works.

The authorities said the acquisition and demolition of the Thomson Road building will not have an impact on the construction timeline of the NSC.

Previously slated to be completed in 2026, work on the NSC has been delayed by a year until 2027 due to Covid-19.

Construction of the corridor, which will connect towns in the northern region to the city, began in 2018 after the first civil contract was awarded in 2017 for a stretch between Novena Rise and Toa Payoh Rise.

Since then, all 14 civil contracts for the construction of the corridor's tunnels and viaducts have been awarded, with the final batch awarded in late 2019.

The corridor was originally intended to be a vehicular expressway but was later reconfigured to include dedicated bus lanes, cycling trunk routes and pedestrian paths, making it Singapore's first integrated transport corridor.

When it is completed, bus journeys from towns in the north such as Woodlands, Sembawang and Ang Mo Kio to the city could be 10 to 15 minutes shorter.

The corridor, which will run almost parallel to the Central Expressway (CTE), will also alleviate traffic on the CTE and major arterial roads such as Thomson Road and Marymount Road.

Meanwhile, the corridor's cycling trunk routes and pedestrian paths will link up with the Park Connector Network and local cycling paths within HDB towns along the entire corridor.

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