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Sydney Desalination Plant – Guaranteeing water security for Sydney


In June 2014, Veolia worked with John Holland in a joint venture (Blue Water) to design and build Sydney’s Desalination Plant on behalf of Sydney Water. Veolia is now operating and maintaining the plant and intake/outlet structures under a 20 year contract.

Sydney Desalination Plant
 

THE CHALLENGE

The city of Sydney is solely reliant on surrounding dams and rain for its drinking water. With Sydney’s growing population and uncertain rainfall predictions due to climate change, the New South Wales Government recognised the need for a new, non-rainfall dependent source of water to secure the city’s water supplies for the future.

The Government announced the decision to proceed with the desalination plant in February 2007 when dam levels were at 34.1 per cent and dropping approximately 0.4 per cent per week. If dam levels had continued to decline at this rate, drinking water storage would have been ten per cent by July 2009 creating a risk of Sydney running out of water.
 
 

 

THE SOLUTION

In June 2014, Veolia worked with John Holland in a joint venture (Blue Water) to design and build Sydney’s Desalination Plant on behalf of Sydney Water. Veolia is now operating and maintaining the plant and intake/outlet structures under a 20 year contract.

Ownership of the plant has recently been transferred to the Ontario Teacher’s Pension Plan (OTPP) and Hastings Fund Management (HFM), who have retained Veolia as the operator of the plant.

On behalf of Sydney Water, the Blue Water Joint Venture (Veolia and John Holland) constructed the plant which Veolia is now operating and maintaining. The scope of this project included:
  • 250 megalitres per day seawater reverse osmosis desalination plant
  • 2 x 2.5 kilometre tunnels
  • Intake and outlet risers (located approximately 200 – 300 metres offshore).

The plant is located on a 45 hectare site at Kurnell and includes a 15 hectare environmental conservation area.

The plant can supply an average of 250 megalitres of safe drinking water a day. This is the equivalent of approximately 15 per cent of Sydney’s water supply. Essentially, seawater is treated using reverse osmosis which pushes seawater through membranes where salt and any other impurities are removed, producing freshwater.

The plant is currently in water security mode. Care and maintenance operations will continue until dam levels fall below 70%, when the restart process will begin. The plant will then continue to produce drinking water until dam levels rise above 80%.

CONVERTING SEAWATER INTO HIGH QUALITY DRINKING WATER
  1. Seawater is drawn via an underground and undersea tunnel
  2. Pre-treatment filters remove smaller particles
  3. Filtered seawater is pumped into the reverse osmosis building
  4. Waste from the pre-treatment filtration process is either reused or removed for disposal
  5. Seawater is pushed at high pressure through reverse osmosis membranes to remove salt and minerals
  6. Fluoride and minerals are added to the fresh water
  7. Water is stored in the drinking water holding tank and then pumped to the Sydney Water network through a pipeline
  8. Seawater concentrate is returned to the ocean.
 

THE RESULT

  • A key component of Sydney’s water supply security and will help guarantee water supply even in years of drought
  • Can produce an average of 250 million litres per day of high quality drinking water for up to 1 .5 million people
  • Reduces the time the community spends in drought restrictions
  • Reduces the likelihood that there will need to be further investment to augment supply
  • Supports environmental flow regimes
  • Maintenance program optimisation extending the life of plant assets.
 

KEY FIGURES

  • Produce up to 250 million litres per day of high quality drinking water
  • Capacity to provide drinking water to 1.5 million people