TUAS 3 Desalination Plant


HSL Constructor Pte Ltd was awarded the D&C contract for the TUAS 3 desalination plant by the Singapore National Water Agency, PUB. This would be Singapore’s third desalination plant and boost the country’s desalination capacity to a drinking water production capacity of 136,000 m3/day, making it one of the largest reverse osmosis desalination plants in the region. It would also help meet up to 30 per cent of Singapore’s current water demand.


Jacobs was nominated by PUB as the engineering firm to supervise the complete project and Tedagua (ACS Group) was appointed as a key engineering subcontractor by HSL to undertake works including the process, electrical and instrumentation packages. SPIN AU was awarded the design of the Control System by Tedagua.


This engineering work included the Control System Architecture, fieldbus calculations, the electrical design of all control cubicles and the production of functional control specifications (FCS). The control system was designed using Siemens’ DCS PCS7 in high availability configuration so that all control system networks and equipment could accept multiple points of failure.


Not having had local representation in Singapore at the time, the award to SPIN demonstrates the trust contractors place in our company’s track record delivering controls systems solutions for water infrastructure projects. In particular, our experience and strong knowledge of the desalination process.



Key responsibilities:

  • Develop Functional Specification
  • Design the Control System Architecture based on Redundant PLCs
  • Design of the Ethernet and Fieldbus Networks
  • Development of IO and Instrumentation Lists
  • Electrical Engineering for 50 control cubicles, including detailed electrical drawings, control cubicle layout, cable and equipment list and field equipment detailed connection
  • Connections to vendors packages control systems.


The Control System Platform:

  • Siemens PCS7 DCS