SINGAPORE — Sato Kogyo, the construction firm whose unauthorised work on the public drainage system contributed to flash floods along Upper Thomson Road on Christmas Eve last year, has changed drain covers to open ones to facilitate the flow of water and has used sandbags to prevent water from flowing into shophouses.

Providing an update after a flash flood struck the area on Thursday (Jan 19), national water agency PUB and the Land Transport Authority said the measures were “temporary improvement works to increase the drainage capacity in the area” since the Dec 24 incident. The sandbags are placed at the edge of the five-foot ways that front the shops along Upper Thomson Road.

Earlier this week, PUB announced that it had discovered unauthorised work on the public drainage system by Sato Kogyo, which is the LTA’s contractor for the Upper Thomson MRT Station project.

Sato Kogyo had constructed an under-sized temporary diversion drain within its worksite, and had not informed PUB before it started the work. The contractor had also altered the public drainage system across Upper Thomson Road, near Lorong Mega, without PUB’s approval and faces sanctions under the Sewerage and Drainage Act.

As intense rain fell over central Singapore on Thursday, a flash flood occurred at the junction of Upper Thomson Road and Jalan Lembah Thomson for about 20 minutes, from 3.44pm to 4.05pm. The Government agencies said 59.2mm of rainfall was recorded at Lower Peirce Reservoir from 3.10pm to 4pm.

But unlike the knee-deep waters on Dec 24 that damaged the equipment of shops such as The Roti Prata House, shophouses nearby were not affected this time.

The LTA said it has instructed Sato Kogyo to speed up the completion of canal-widening along Jalan Keli. Once it is completed early in the third quarter of this year, the area will have better protection against floods.

PUB advised the public to be cautious as flash floods may occur in the event of heavy storms. The public may also report flash floods or check on the flood situation via PUB’s Facebook page, its call centre (1800 2255 782) or its MyWaters mobile app.