Following the completion of the underpass tunnel through the KL-Seremban Highway near Sungai Besi, construction of the MRT Sungai Buloh-Serdang-Putrajaya (SSP) Line is now over 70% done.

MRT Corp SSP Line project director Datuk Amiruddin Ma’aris said the breakthrough, which took place last Saturday, marked the completion of excavation works for the second of two tunnels, located between 4.7m and 5m beneath the busy highway. The first tunnel breakthrough happened on February 25, Bernama reported.

“The success of the V204 underpass construction shows the strong commitment of MRT Corp as project owner, the construction team from MMC Gamuda KVMRT as the turnkey contractor and WCT Bhd as the work package contractor to deliver the project according to schedule,” he said in a statement.

Located between the Taman Naga Emas and Sungai Besi stations, the pair of tunnels have a diameter of 5.8m and are 60 metres in length. Construction was done using a combination of methods, such as micro-tunnelling using mini-sized 0.8 diameter tunnel boring machines, and pipe-jacking to construct an arch for excavation to be carried out. Construction started in March 2019, and throughout the period, the very busy expressway above remained open to traffic.

Amiruddin said that phase one of the MRT SSP Line between the Kwasa Damansara and Kampung Batu stations should be operational by the middle of 2021, with the rest of the line scheduled to open by 2022.