Service difficulties
and emergency
service: 13 20 90
Replacement Flows Project
You can email the
Replacement Flows Project
team, call 1800 506 633 or
write to:
Replacement Flows Project
PO Box 653
St Marys NSW 1790
Overview of the scheme.
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Image of St Marys
Recycled Water Plant.
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Hawkesbury-Nepean River
The Replacement Flows Project is Sydney's largest water recycling project. It is a key part of the NSW Government's Metropolitan Water Plan. It plays a critical role in increasing water recycling in the Sydney region to 70 billion litres a year by 2015.
How will the project work?
The Replacement Flows Project is designed to save drinking water and maintain river health. It will provide up to 18 billion litres of highly treated recycled water each year to the Hawkesbury-Nepean River system. This will replace water that is currently released from Warragamba Dam to maintain environmental flows.
Wastewater from St Marys, Penrith and Quakers Hill sewage treatment plants will be treated at a new recycled water plant next to St Marys Sewage Treatment Plant.
Sydney Water has built pipelines to carry treated wastewater and recycled water between the plants. After treatment at St Marys, the highly treated recycled water will be pumped back to Penrith. It will then be released into the Hawkesbury-Nepean River below Penrith Weir.
Sydney Water has upgraded an existing pipeline between Quakers Hill and Seven Hills to carry concentrate waste from the recycled water plant. We have also built a pipeline from Seven Hills to Oatlands to connect with the northern Sydney sewerage system.
We are working with Deerubbin WaterFutures, a consortium of companies consisting of United Group Infrastructure, McConnell Dowell Constructors (Aust) and GE Water and Process Technologies to deliver this major water recycling project.
What is the timetable for the project?
In May 2008, construction of the pipelines and recycled water plant started and now it's nearly complete.
All major construction on the recycled water plant, except for the reverse osmosis membranes, was finished in January 2010. An extensive program of testing will take place over the coming months.
From September 2010 the plant is scheduled to become fully operational.