Catering for growth in Sydney’s North West
Veolia recently completed work on Sydney Water’s North West Growth Centre (NWGC) Riverstone Wastewater Package 2. Trenchless Australasia takes a closer look at the project and how the NWGC will service the growing population of Australia’s largest city.
The NWGC package of works commenced in 2006 when the NSW Minister for Planning announced the first release of land in the area.
The land release is collectively known as the First Release Precincts and includes North Kellyville, Alex Avenue, Riverstone, Riverstone West, Colebee and Area 20.
Package 1 of the NWGC, which has now been completed, included the construction of a new drinking reservoir and approximately 23 km of drinking water, recycled water and wastewater pipelines.
In addition to this, new services were provided in the Riverstone and Alex Avenue Precincts including:
- A 40 million litre drinking water reservoir and associated connection work on our land at Cudgegong Road in Rouse Hill
- Drinking water pipelines to service the new precincts
- A wastewater pipeline to service the Alex Avenue precinct.
Sydney Water has a number of water and wastewater infrastructure projects planned as part of the North West Growth Centre (NWGC) package of works, which is designed to cater for projected population growth and new housing developments.
Packages 2 and 3A of the NWGC project commenced in early 2013. Veolia’s work on the NWGC was part of Package 2 and included the installation of three wastewater lead-ins in Riverstone. Totalling 3.1 km, these leads in were:
- Wastewater lead in 1 – 1.4 km, DN375 PP, DN375 GRP, DN375 and DN300 PVCU
- Wastewater lead in 2 – 0.9 km, DN300 GRP and DN300 PVCU
- Wastewater lead in 3 – 0.8 km, DN300 GRP and DN300 PVCU.
Veolia was awarded the contract on 19 October 2015, commenced works on 10 December 2015, and completed the project on 18 July 2016.
The lead ins were constructed using open cut trenching and microtunnelling, with Veolia awarding the microtunnelling subcontract to Pezzimenti Tunnelbore.
Microtunnelling was selected to complete the work as it was determined to be a more accurate and cost-effective method when compared to horizontal directional drilling (HDD) and thrust boring.
The contracted works also covered clearing project corridors; constructing the sewer lead-in main to be connected to the existing maintenance holes on the Chain of Ponds Carrier; constructing all inlets, maintenance holes, vent shafts and other structures associated with the sewer; and constructing the connection to the existing carriers.
Excavating the access shafts and identifying areas to store potential excavation spoil were some of the key challenges of project delivery.
Community consultation was another major consideration, with commercial properties and private houses located very close to the project works.
The project has now been finalised on time, with no major non-conformance. The key to the success of this project was the high level of project management, strong planning skills, and high-level focus on safety performance.
The next stage of the NWGC project includes Packages 3B, 3C, and 3D. Work on these packages commenced in mid-2016 and is expected to be completed by mid-2018.
Vineyard, Riverstone East, Riverstone West, North Kellyville, Box Hill, Box Hill Industrial, Alex Avenue, Schofields and Schofields West Precincts are all included in these packages of works.
For more information visit the Veolia website.
This article was featured in the December edition of Trenchless Australasia. To view the magazine on your PC, Mac, tablet, or mobile device, click here.
If you have a project you would like covered in Trenchless Australasia contact Assistant Editor Nick Lovering at email@example.com