Construction begins on $4.8bn underground tunnels for used water in Singapore
November 22, 2017 – The Singapore’s Public Utilities Board (PUB) has broken ground on the second phase of the deep tunnel sewerage system (DTSS) to transport used water, freeing up land above for redevelopment. The second phase, which will measure 100km in length, will entail an investment of SGD6.5bn ($4.8bn).
According to the plan, 19 tunnel boring machines will be deployed to dig at depths of between 35m to 55m below ground and under the sea to build 40km of deep tunnels and 10km of link sewers. The remaining 50km of link sewers will be constructed using a micro-tunnelling method called pipe jacking.
Upon completion in 2025, the tunnel will transport used water to water reclamation plants and free up approximately 83 hectares of land.
The second phase of the DTSS will serve the western part of Singapore, including the downtown area and upcoming major developments such as Tengah Town and Jurong Lake District. Starting from Keppel Road, the tunnel will run mostly under the Ayer Rajah Expressway and will cross undersea at Tuas Bay, and end at the upcoming Tuas Water Reclamation Plant, where a new NEWater factory will be constructed. DTSS will carry all of the island’s used water to water reclamation plants in Changi, Kranji and Tuas, where it will be treated and purified to produce NEWater, or will be discharged into the sea.