The leftmost lane of Farrer Underpass and a section of a slip road from Holland Road to Farrer Road have been fully reopened, more than three months after tunnelling works caused part of Farrer Road to cave in.
According to a tweet by the Land Transport Authority last Friday (March 3), works at Farrer Road to strengthen and stabilise the affected area have been completed.
On Nov 15, 2022, a machine involved in excavating a tunnel for national water agency PUB's Deep Tunnel Sewerage System (DTSS) Phase 2 was undergoing maintenance when the ground in front of it destabilised, the Building and Construction Authority (BCA) said in an update in January.
This caused a sinkhole to form on the slip road leading from Holland Road to Farrer Road. No one was injured, but the slip road was closed to traffic for about a week.
A short section of Farrer Road after the slip road was closed to facilitate grouting and strengthening works, BCA added. In grouting, a mixture of materials such as sand, water and cement is pumped into the ground or structures to stabilise them.
A section of the leftmost lane of Farrer Underpass was also closed to ensure vehicles coming out of the slip road can merge safely into Farrer Road.
BCA said in a statement on Sunday that it is investigating whether there have been any contraventions of the Building Control Act and Regulations and will consider the appropriate enforcement action after investigations have been completed.
The stop-work order for the DTSS2 tunnelling works is still in force, and the works will be allowed to resume after additional measures are put in place to ensure safety, said the authority.
The DTSS project is undertaken by Japanese construction firm Nishimatsu.
This is not the first time tunnelling work has caused such an incident in the area.
In 2008, tunnelling for the MRT Circle Line caused a cave-in in the vicinity. An eight metres by seven metres stretch of Cornwall Gardens in Holland Village — barely 200 metres from the damaged Farrer Road — sank into a three metres deep crater.
This article was first published in The Straits Times. Permission required for reproduction.
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