PUB starts second phase of DTSS with S$2.3b of work contracted out

SINGAPORE'S national water agency PUB has begun the second phase of the Deep Tunnel Sewerage System (DTSS) with five contracts worth a total of S$2.3 billion already contracted out.

The PUB held a groundbreaking ceremony - witnessed by Minister for the Environment and Water Resources, Masagos Zulkifli, to mark the start of construction works for the enhanced conveyance system. The ceremony was held at the site of phase two's first tunnelling shaft at Penjuru Road.

Ed Zublin, Leighton Contractors, Nishimatsu Construction, Shanghai Tunnel Engineering Co (Singapore) and a joint-venture between Penta-Ocean Construction and Koh Brothers, have already been contracted to work on about 50 kilometres of tunnels for phase two.

The second phase - which is expected to be completed in 2025 - will see the extension of the deep tunnel system to cover the western part of Singapore, including the downtown area and major upcoming developments such as Tengah Town and Jurong Lake District.

The tunnels in phase two will connect to existing tunnels from the first phase - which serve the eastern part of Singapore and the public sewer network - to create an integrated system, the PUB said in a release on Monday.

"The 100-kilometre used water conveyance network for DTSS phase two will run largely under the Ayer Rajah Expressway (AYE), crossing undersea at Tuas Bay and ending at deep inlet shafts within the future Tuas Water Reclamation Plant," the PUB said.

"With the DTSS, used water will be conveyed from the DTSS to three centralised water reclamation plants - Changi, Tuas and Kranji - for treatment, before it undergoes further purification to produce NEWater, or discharged into the sea," the agency added.

Yong Wei Hin, PUB's director of DTSS phase two, said: "The DTSS is a more cost-effective and sustainable way of meeting Singapore's used water needs and securing NEWater supply for the future than simply renewing and expanding the existing conventional used water infrastructure. PUB will continue to harness advanced technologies to enhance Singapore's used water management system and ensure its water sustainability for the future."

Once it is fully completed, the DTSS will result in a 50 per cent reduction in land taken up by used water infrastructure, from 300 hectares in the 1990s to 150 hectares in the long term.