TWO soil depressions and a sinkhole, discovered in Jalan Bukit Bintang has resulted in the closure of a 500m stretch of the road between Chulan Square and Menara Worldwide until further notice.
The first depression was discovered at 9am during underground tunnelling works for the Klang Valley Mass Rapid Transit (KVMRT) project on Wednesday and immediate repairs were undertaken by the contractor MMC Gamuda KVMRT (T) Sdn Bhd.
MRT Corp Strategic Communications and Public Relations director Amir Mahmood Razak said grouting (cement) was pumped into the first depression underneath the pedestrian walkway to strengthen the loose soil.
A new minor depression was discovered about 1m away from the first on Thursday and similar rectification work is being carried out there as well.
Additionally, a sinkhole, measuring 10m in length, 3.5m wide and about 2m deep, appeared in the same location as the two earlier soil depressions at 10.42pm on Thursday night.
MRT Corp and MMC Gamuda engineers have begun backfilling the sinkhole, to be followed by compaction grouting and road repairs.
During the closure, a traffic contra-flow has been implemented whereby traffic from Bukit Bintang heading to Jalan Tun Razak is being directed to two lanes on the other side of the road.
Two remaining lanes are still open to Bukit Bintang-bound traffic.
Alternatively, road users from Bukit Bintang to Jalan Tun Razak can turn into Jalan Imbi at Chulan Square, then turn left into Jalan Inai, another left into Jalan Kampung and rejoin Jalan Bukit Bintang at the traffic lights opposite Bangunan Yayasan Tun Razak, to turn right into Jalan Tun Razak.
Motorists can also go straight along Jalan Inai and reach Jalan Tun Razak directly near the Indonesian Embassy building.
A third alternative is to go along Jalan Imbi, turn left at the SMART tunnel entrance road, and proceed to the Kampung Pandan roundabout, where motorists can access Jalan Tun Razak.
Access to both Bangunan LTAT and Menara Worldwide is affected, as tenants and visitors to the former can access the building’s basement parking, but the slip road to rejoin Jalan Bukit Bintang will be closed.
Tenants and visitors to Menara Worldwide will need to follow the contra lanes along Jalan Bukit Bintang and turn left at the end of the road divider.
According to Amir Mahmood, the depressions and sinkholes were caused by the Kuala Lumpur limestone formation.
“This geological formation is extremely challenging to tunnel through because there is the possibility of voids, cavities and other irregular rock formations,” said Amir Mahmood.
He added that to mitigate such risks, the company had conducted prior soil investigations, surface-monitoring and was using a specialised tunnel boring machine for limestone formations.
Both traffic police and MMC Gamuda’s Emergency Response Team will be on the ground to help direct traffic during the closure.