The project involves improvement of existing trapezoid drain (top width 10m – 11m) reconstructed to U-drain (top width 11.45m – 14.31m). The depth of the constructed drain was deeper by 1.0-1.5m from existing 3.5m depth. Reconstruction of the existing Twin Cell culvert near Swiss Club Road to Triple Cell Culvert. Supplementary Box culverts 3.4m(W) and 6.6m(W) on both side of an existing twin cell culvert across Bukit Timah Road. The total length of drain improvement works is more than 600m. The construction works commenced on November 2010 and the project was Substantially Completed on March 2013.

We carried out all the permanent works civil structure design and obtained all the necessary approvals from all authorities before commencement of construction. There is limited working space constraints along Bukit Timah Road and trees along Dunearn. Loading/Unloading of work material and soil involved temporary closure of one lane of Bukit Timah Road and Dunearn Road. Construction of Triple Cell Culvert and Two Supplementary Cell Culvert across major road involved traffic diversion and lane-for-lane replacement to maintain existing road capacity. We prepared and obtained approval for the notional traffic diversion scheme for contractors reference. Construction carried out in stages according to approved Traffic Control Plan. Next stage allowed to proceed only after previous stage completed. Numerous services such as telecoms, potable water, electrical power, power gas mains etc required to be diverted first before carrying out the drain improvement works. The project requires extensive coordination and submissions to authorities and services agencies.