Used water superhighway for the next 100 years

A superhighway for used water management, the Deep Tunnel Sewerage System (DTSS) is an efficient and cost-efficient solution conceived by PUB to meet Singapore’s long-term needs for used water collection, treatment, reclamation and disposal.


The concept of the DTSS is to use deep tunnel sewers to convey used water by gravity to centralised water reclamation plants (WRPs) located at the coastal areas. The used water is then treated and further purified into ultra-clean, high-grade reclaimed water called NEWater, or discharged to the sea through the outfalls.

The development of DTSS is a key part of our long-term used water system which comprises a network of link sewers leading to two major tunnels criss-crossing Singapore with three large WRPs at the northern (Kranji), eastern (Changi) and western (Tuas) ends of Singapore, as well as outfall pipes.

Click here to see how DTSS works.


International Recognition

Crowned ‘Water Project of the Year’ at the Global Water Awards 2009 in Zurich, Switzerland on 28 April 2009, the DTSS was selected as the water project with the most significant contribution to water technology and environmental protection. The annual Global Water Awards is widely recognised as one of the most prestigious symbols of achievement in the global water industry.

Last updated on 7 Jan 2015