4 days ago
Tanjong Katong sinkhole: Singapore's national water agency orders review of similar sewer works across city-state
SINGAPORE, July 28 — Singapore's national water agency PUB said yesterday it will call for a time-out to review the safety of ongoing sewer works similar to those near the sinkhole that opened up along Tanjong Katong Road on Saturday.
According to Channel News Asia, the sinkhole, about two to three metres deep and as wide as two lanes, appeared adjacent to an active PUB worksite involving the construction of a 16-metre-deep shaft linking three sewer lines.
PUB said a 'concrete component in the shaft failed at around 5.50pm', around the same time a car plunged into the road after the collapse.
The agency identified the failed part as a caisson ring, describing it as 'a watertight retaining structure that allows water to be pumped out, keeping the work area dry.'
'The shaft has been backfilled to stabilise the surrounding ground,' it said.
As a precaution, PUB said, 'The agency will call for a time-out to review and ensure the safety of similar sewer construction works across Singapore.'
The sinkhole was later filled with liquefied stabilised soil, with reinstatement works expected to begin after the area is fully stabilised.
The Land Transport Authority said Tanjong Katong Road South, between Mountbatten Road and the East Coast Parkway (ECP), will remain closed until further notice.
Bus services 36 and 48 have been diverted.
PUB said the driver who fell into the sinkhole managed to climb out of her vehicle and was rescued by construction workers within five minutes.
She was taken conscious to Raffles Hospital.
PUB noted: 'The damage to the water pipes had contributed to the filling of water in the sinkhole. This ceased once the mains were shut off.'
The agency said it began pumping water out of the sinkhole at 9.45am Sunday and completed the task by 1.20pm.
The car was retrieved at 2pm the same day.
PUB also reported water supply disruptions affecting 18 households in the area from around 6pm Saturday.
'Preliminary findings suggest that the water mains may have been damaged as a result of ground movement associated with the sinkhole,' it said.
Water supply was fully restored by 2.30am on Sunday after the affected pipes were isolated.
PUB said it is working closely with the Building and Construction Authority (BCA) and the LTA on repair works and investigations into the incident.
The agency also confirmed a ground-penetrating radar scan was conducted and is still being analysed.
In its latest update yesterday morning, PUB added: 'Engineers from BCA have checked and affirmed that nearby structures, including One Amber condominium and the landed homes across the road, are not affected by the incident.'
Motorists and commuters have been advised to plan ahead and expect delays during weekday peak hours.
