SINGAPORE – Three contractors have been appointed by Singapore national water agency PUB to design and build the first batch of 30 km of deep tunnels and link sewers for the Deep Tunnel SewerageSystem (DTSS) Phase 2.
The three successful companies include Ed Zublin AG (Singapore Branch), Penta-Ocean Construction Co., Ltd. and Koh Brothers Building & Civil Engineering Contractor (Pte.) Ltd. Joint Venture, and Leighton Contractors (Asia) Limited (Singapore Branch) –
These are part of a network of 40 km of deep tunnels and 60 km of link sewers for DTSS Phase 2 which will be built using the tunnelling method. The subsequent contracts to build the rest of the deep tunnels and link sewers will be awarded from 2018.
The contractors were appointed following a pre-qualification and tender exercise in mid-2016, with the three contracts valued at a total of S$1.51 billion.
Over the next seven years, they will develop the detailed design and construct some 30 km of deep tunnels and link sewers as well as the associated ancillary structures.
This network of 100 km of deep tunnels and link sewers will connect to the Tuas Water Reclamation Plant, which is expected to be completed in 2025. By then, the whole of Singapore will be served by the DTSS.
Used water will be conveyed from the DTSS via gravity to three centralised water reclamation plants for treatment, before it undergoes further purification to produce NEWater, or discharged into the sea.
A joint venture between consultancies Black & Veatch and AECOM are leading the DTSS Phase 2.
Mr Yong Wei Hin, Director of DTSS Phase 2 at PUB, said: “The deep tunnels are an integral part of the DTSS, conveying every drop of used water for treatment and channelling it for further reclamation into NEWater. As the backbone of NEWater production, the DTSS ensures the sustainability and resilience of the used water network to facilitate large-scale water recycling in Singapore, and contributes to the goal of increasing the overall water recycling rate from 40% to up to 55% of total water demand in the long term.”