As the first common services tunnel in Southeast Asia, Marina Bay CST is a modern infrastructure project consisting of an underground network of tunnels. CST houses all the cable and pipeline systems for electricity, water, energy, and telecommunications to distribute to all the development areas in Marina Bay.

The URA has been designated as the CST authority responsible for managing the CST Act for the Marina Bay CST area since January 7, 2021. Before undertaking any engineering works in the Marina Bay CST protected area or placing any utility infrastructure facilities within the CST area, written approval from the URA is required.

CST was also constructed at a time when other major infrastructure works, such as the Mass Rapid Transit (MRT) tunnels, sewers, and underground pedestrian networks, were underway. At its deepest point, CST had to pass under train tunnels at a depth of 30 meters (equivalent to a 10-story building underground), posing challenges for temporary retaining works.

Construction was carried out in phases to integrate with the overall planning and development of Marina Bay. With utility pipes and cables housed within a concrete tunnel, service reliability is enhanced as pipes and cables can be regularly inspected and maintained. The tunnel allows for the installation of new services to meet future demands. It is spacious enough for people to walk through, maximizing the use of underground space and saving ground-level space – approximately 1.6 hectares, equivalent to two soccer fields, in Marina Bay alone.