Construction firm, 6 people charged over Tanjong Katong sinkhole incident in 2025

A construction company and six people linked to the firm’s project have been charged in court over the Tanjong Katong Road sinkhole incident in 2025 which led to a driver suffering injuries when her car plunged into the pit.

Ohin Construction and the six individuals were hauled to court on June 11. They were handed various charges, mostly under the Workplace Safety and Health Act and Building Control Act.

According to court documents, Ohin Construction was to conduct ground support and stabilisation specialist building works at the site but had failed to ensure that the works were carried out in accordance with approved structural plans.

The licensed specialist builder had allegedly constructed 27 jet grout piles with smaller diameters than stipulated in the plans, and allegedly failed to carry out tests for penetration and strength.

Jet grouting, which is often used for bracing walls during excavations, involves using a high velocity jet of fluids to cut the soil and mix this with a self-hardening grout to form columns.

There were also issues with the reinforced concrete caisson rings used in the project.

Caisson rings are concrete structures that provide structural support for deep excavations. They are installed progressively as excavation deepens to prevent soil collapse.

According to court documents, Ohin Construction created openings in a caisson ring and horizontal grouting works at another ring that were not approved. One of the rings was allegedly cast in a non-circular shape instead of a uniformly circular one.

The court heard that Ohin Construction has been provisionally liquidated. A representative for the liquidators was present in court.

The individuals charged in court over the incident included Ohin Construction’s managing director Ivan Ong Khiaw Yang, 64, project director Raajkumar Nadarajan, 58, and project manager Sellappan Saravanakumar, 35.

Kee Chen Siang, 39, and Yau Tze Yin, 49, identified as “qualified persons”, and resident engineer Senthilnathan Mathyalakan, 56, were also charged.

Their alleged offences involved unauthorised and non-compliant works, licensing and supervisory failures, testing and monitoring lapses, and the failure to notify authorities of the road depression that had occurred before the sinkhole formed.

The cases will be heard again in court in July.

The large sinkhole in Tanjong Katong Road South had appeared suddenly at about 5.50pm on July 26, 2025, as two lanes of the road collapsed into a large pit.

A woman was taken to hospital after the car she was driving fell into the sinkhole that formed at the junction of Tanjong Katong Road and Mountbatten Road, adjacent to a PUB worksite.

Videos posted online showed a black car falling into the sinkhole when the ground suddenly gave way under the vehicle.

The woman was rescued by construction workers who pulled her out of the hole.

At a briefing the day after the incident, PUB, Singapore’s national water agency, said a caisson ring had shown signs of failure around the same time the sinkhole formed.

The structure was located at an adjacent PUB worksite, where a 16m-deep shaft was being constructed to connect three existing sewer lines.

The shaft would have allowed Ohin Construction to access the underground sewer lines.

Engineers from the Building and Construction Authority (BCA) later conducted checks on the nearby One Amber condominium and the landed houses across the road.

The assessments confirmed that the buildings were not affected by the incident.

The Ministry of Sustainability and the Environment had said it would convene an internal panel to investigate the cause of the sinkhole.

Meanwhile, the Ministry of Manpower, Land Transport Authority and BCA said in a joint statement that they have completed their respective investigations, adding that conditional warnings have been given to PUB and Surbana Jurong Consultants under the Building Control Act.

Works for the project remain halted.

“For works to resume, the new project parties to be appointed by PUB will have to submit new structural plans, which will be subjected to comprehensive safety assessments and approval by the BCA Commissioner of Building Control,” the agencies added.

Source: The Straits Times © SPH Media Limited. Permission required for reproduction.

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