soil surrounding the station site via jet grouting. Sheet piles were installed around the site, and tests were conducted to determine the amount of saltwater and groundwater at the site. The contractor initially considered rerouting the drainage system that channelled water to the sea but that was financially unfeasible. Instead, the culverts that crossed the site were cut open and diverted into temporary steel culverts or pipes that did not obstruct the works. Due to the limited space, two of the World Trade Centre's exhibition halls were demolished to facilitate construction works. Concurrently, the Telok Blangah Road was being upgraded with a new vehicular overpass being constructed. Hence, the LTA's road and rail project teams had to coordinate to maximise the efficiency of both projects. The rail project team had constructed 10 viaduct foundations for the road section that crosses the station site. At the same time, the contractor had to maintain the traffic flow in the area – not just for visitors to the World Trade Centre, but to prevent delays and disruptions to port operations nearby. The traffic was diverted to temporary steel decking that ran over the construction site. The roads were diverted at least 30 times for the station's construction. The contractors (Shimira Corporation, Koh Brothers, Dillingham Construction International) for the of tunnelling works between this station and the adjacent Outram Park station had to monitor for any ground movement for the shophouses and ensure operations for the Malaysian rail service was not affected. A dual-mode tunnel boring machine was used to deal with the varying soil conditions along the tunnel route. HarbourFront station opened on 20 June 2003 with the rest of the NEL stations. In October 2012, the LTA announced that the NEL overrun tunnel would be extended by . Completed at the end of 2014 at a cost of S$8.2 million (US$ million), the extension is to facilitate quicker turnarounds for southbound trains. As part of a joint emergency preparedness exercise by the LTA and train operators SBS Transit and SMRT, security screenings were held at the station on 2 August 2019. The screening machines deployed for the exercise include mass screening devices and X-Ray machines to check for possible threat items like firearms. Such exercises were conducted to test established response protocols and maintain vigilance for quicker and more effective responses during emergencies and heightened security situations. Circle line In 2001, Yeo