Sydney Water’s $90 million upgrade to the North West Growth Area aims to provide essential water infrastructure that will secure the city’s future housing development.
Sydney’s north-west is becoming an increasingly popular place to live. With the area’s population expected to increase dramatically in the coming years, the New South Wales Government is investing in developing the housing and supporting infrastructure that will support this growth.
The area is expected to have 17,000 homes by mid-2025 and 33,000 homes by 2026. Once fully developed, it is estimated to be home to around 250,000 people.
Sydney Water Senior Project Manager, James Paton, said that the North West Growth Area is an important area for Sydney Water and for Sydney as a whole.
“We’re expecting 150,000 people to come to the area over the next few years and Sydney Water is trying to support that additional growth through the delivery of our drinking water and wastewater projects,” Mr Paton said.
“There’s a number of different upgrades that we’re undertaking. There are new drinking water mains to service Marsden Park and the Marsden Park Industrial Precinct. We’re also extending some existing drinking water mains in the area as well.”
Mr Paton said that there are a number of pressure main works and other modifications being undertaken to improve wastewater services in the Marsden Park, Riverstone, Vineyard and Box Hill areas.
“It’s essentially to enable growth to continue expanding and have reliable water and wastewater services.
“The overall project itself has been going on for a number of years. Through 2021-23 the project went through concept design and detailed design, and now construction has been going since July 2023.
“The drinking water components are 80 per cent complete. The wastewater sections are approximately 70 per cent complete.”
The wastewater works are expected to be completed and operational in 2025.
Better outcomes for all
Mr Paton explained that Sydney Water has a number of internal specialists that help it to deliver positive environmental and community outcomes through the project, from design to construction.
“Our delivery partners also have resources that are specific for enabling positive outcomes.
“With this project, management of the noise impact was one of the higher risk factors for us because we’re going through a number of residential areas and at night too.
“That was one of the big environmental factors that we needed to try and mitigate. Notifications for the community is one thing, and also just trying to implement strategies and mitigation measures so we can actually reduce the noise of our construction.”
Mr Paton said that it was important to consult with the community on these measures.
“We survey the community and get feedback from them such as; when are the best times and days? Do they want us to and work five days a week and complete the project quicker, or would they rather an extra respite day and a four-day week even though the project will take longer?
“That’s the sort of consultation we do with the community. That goes a long way and really helps everyone. We are a part of the community, and we try and work with the community to provide better outcomes for them and for the environment.”
Servicing new developments
Mr Paton said that many of the works being undertaken as part of the project are to amplify existing systems to accommodate for future growth and developments.
“Otherwise, the communities wouldn’t receive the reliable pressure or the water quality that they expect from a high-class water provider such as Sydney Water.”
Mr Paton said that for the majority of cases, open-trench was the most efficient technique and the most commonly used.
“There are obviously exceptions to that. Sometimes we need to use microtunnelling to avoid impacting on the roads, the rail lines, or the developer’s property that we need to go underneath. Depending on the depth of cover, this also minimises disturbances to landowners and their tenants, leading to the best outcome for the project.”
Mr Paton said that microtunnelling is more complex and more technical than open-trenching.
“It does take a little bit longer to undertake and a little bit more time to design.
“On this project, we can construct shafts approximately 10m deep, and then we microtunnel underneath the property, and that essentially removes any impact to the surface other than the construction shafts themselves.
“We really minimise impact to the local businesses in that area, and also to the road and the rails. It’s essential that we work with the service providers such as Sydney Trains and the local council, to make sure we reduce impact to those main thoroughfares.”
Project challenges
Mr Paton said that as with any project the North West water upgrade has faced a number of challenges, the biggest of which was difficulty with pipe alignments and minimising the disruptions caused by the works.
“For example, with a drinking water line, our alignment was through a main road because we needed to avoid and maintain access to all the other services, as well as trying to minimise impact to the bus routes, local traffic and council activities.
“In terms of wastewater challenges, where possible we minimised our long‑term impacts to private properties. To minimise our footprint and easement impacts, we tried to consolidate pipes where possible. That was a benefit of utilising the microtunnelling – we were able to combine a number of pipes within a larger encasing pipe, which really reduced the impact to the land above and future use of the land in the future.
“It’s not always possible, because we’re an essential service and we need to have our assets in the ground – sometimes long before the land is developed – but we really try to work with landowners to try and minimise our impacts when possible, and that was a significant challenge on this project.”
Looking to the future
Mr Paton explained that a number of the works undertaken in this project are designed to become building blocks for future development efforts.
“Some of what we’re doing I would call enabling works for future projects. We’re getting through pinch points, and we’ve brought sections of future projects forward into this project.
“For example, as part of one of our microtunnelling sections we’ve included a future pipe for that section, so we won’t have to re-disturb those areas and have to impact the trains or the roads or the developer’s property.
“By bringing those forward, the future projects can then easily be connected onto the pipe we’ve already done, and they will have a more efficient timeframe and cost moving forward.”
Mr Paton said that Sydney Water values the support of its delivery partners.
“We couldn’t do this without them and they have been critical for getting where we are at the moment and ultimately to finishing these projects.
“They’ve been essential to what we do, to doing it safely and efficiently in both time and cost. It’s really good to have the experts in their field along on the project, we couldn’t do it without them. It’s great to have that support from our delivery partners.”
