Lower South Creek

New and upgraded wastewater infrastructure to support an additional half a million people living in Sydney’s North-West by 2040.


  • Sydney, Australia


  • Sydney Water

Project Value

  • AU$400 million

Project Status

  • Due to be completed in December 2018

The Lower South Creek Treatment Program will provide new and upgraded infrastructure to improve quality, capacity and reliability to three Wastewater Treatment Plants (WTPs) – Riverstone, Quakers Hill and St Mary’s – located northwest of Parramatta in Sydney’s rapidly expanding north-western region.


Leading the Way

The program is adopting several innovative process technologies which will be a first for Australia, helping to deliver significant sustainability outcomes, and help pave the way to a more sustainable water services industry. One of these is the transfer of biosolids from Quakers Hill WTP to a regional biosolids hub at St Marys WTP, creating feasibility for a new anaerobic digestion plant with Thermal Hydrolysis Pre-treatment (THP). This will deliver processing efficiencies and allow for co-generation with energy recovery from the biogas produced.


The project is Sydney Water’s first to undertake an independent sustainability certification under the Infrastructure Sustainability Council of Australia’s (ISCA) IS rating tool. It was awarded an Infrastructure Sustainability Design ‘Excellent’ rating – one of the highest ratings ever achieved for an Australian water infrastructure project. Read more about this here.


As part of a Joint Venture and using a Delivery Partner model, WSP is providing program delivery management services, including commercial and design management.


Putting Sustainability at the Forefront

The project will also be Sydney Water’s first to undertake an independent sustainability certification under Infrastructure Sustainability Council of Australia (ISCA) IS Rating tool.