PUB moves to test ground stability at Tanjong Katong sinkhole after filling cavity

The sinkhole appeared on Saturday next to a PUB worksite along Tanjong Katong Road South where sewer-laying works were being done.

A 16m-deep shaft connecting three sewer lines was being constructed at the site.

A concrete component in the shaft, called a caisson ring, failed at around 5.50pm on Saturday, PUB earlier said.

Around the same time, two lanes of the road collapsed, and a car fell into the sinkhole. The driver was rescued by migrant workers and taken conscious to the hospital.

Earlier on Monday, the BCA said that backfilling of the sinkhole and shaft had been completed, which stabilised the site.

Buildings adjacent to the sinkhole remained safe, it said.

BCA also said it would start an independent investigation to identify the root causes of the incident, which could take months.

PUB previously said it would call a time-out to review and ensure the safety of similar sewer construction works.