Singapore to conduct safety review of sewer projects after sinkhole incident

Singapore, July 28 (IANS) Singapore will be calling a safety time-out to review and ensure the safety of similar sewer construction works across the country, following a sinkhole incident near a sewer site, the national water agency, the Public Utilities Board (PUB) said on Monday.

The incident, which occurred on Saturday afternoon along Tanjong Katong Road South in southeastern Singapore, caused a vehicle to fall into the sinkhole. The driver was brought to safety with the assistance of workers on site and was later sent to the hospital for medical attention.

According to reports citing PUB officials, a “concrete component in the shaft failed at around 5.50 pm”, around the same time a car plunged into the road after the collapse.

Shortly after, a disruption to the water supply in the area was reported, affecting 18 households. Preliminary findings suggest that the water mains may have been damaged due to ground movement associated with the sinkhole. The affected pipes were isolated, and a full water supply was restored by early Sunday morning.

The sinkhole formed adjacent to an active PUB construction site where sewer-laying works are ongoing. The works involve constructing a 16-metre-deep shaft to connect three existing sewer lines. On Saturday afternoon, a caisson ring in the shaft was found to have failed, coinciding with the formation of the sinkhole on the nearby road, Xinhua news agency reported.

It is not yet clear if the caisson ring failure and the sinkhole are directly related. The cause of the failure is still under investigation, and a ground-penetrating radar scan and analysis is being conducted to assess the surrounding area.

The sinkhole has since been filled with liquefied stabilised soil to further stabilise the ground, after which road reinstatement works will begin. Recovery efforts are being coordinated under the oversight of the Building and Construction Authority, the Land Transport Authority, and the PUB.

--IANS

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