Watering the West

Tim Jackson7 January 2015, 12:00 am12 February 2016

The population of Melbourne’s outer-western suburbs has been growing at unprecedented rates for a number of years.

Population growth in the three city councils that will be serviced by the pipeline (Brimbank, Melton and Wyndham) has been increasing as much as 10,000-12,000 people a year in some areas.

With the need to provide essential services to this booming population, construction contractor John Holland began work on the project on behalf of Melbourne Water in November 2014.

The project involves the construction of a new water supply main to transfer water from the St Albans reservoir to the Cowies Hill reservoir in Tarneit, with the watermain 17 km in length and diameters of 750 mm and 1,200 mm.

The pipeline is designed to transfer a maximum of 200 ML/d of water, the equivalent of 80 Olympic-sized swimming pools.

The watermain is expected to service approximately 40,000 homes.

Constructing the pipeline

The watermain is located within an existing power line easement and current and future road reserves.

Construction includes the installation of pipework, made up of a combination of mild steel cement lined pipes and glass-fibre reinforced plastic (GRP) pipe, valves, and connections to the existing main at each end of the project.

Melbourne Water Senior Project Manager Peter Clark said that while the project is running on time, there have been several challenges that he has encountered.

“Rock and underground services have been an ongoing issue for the project. We always knew that hard rock would be present along the majority of the alignment, but the hard basalt “˜floaters’ are being found in areas that we don’t expect them,” said
Mr Clark.

“Constructing a large diameter watermain in an urban growth area, the number of underground services (and some above ground) within road reserves is also creating some complexities for the project. Liaising with VicRoads, Councils and other utilities is a day to day task for the project.”

The project is being constructed in accordance with its approved Construction Environmental Management Plan (CEMP) and Cultural Heritage Management Plan (CHMP).

“The project crosses Kororoit Creek, which has the added constraints of environmental and cultural heritage sensitivities. We are continuing to work with DELWP and the Registered Aboriginal Parties for the Kororoit Creek crossing,” said Mr Clark. “Impacts to Ravenhall Grasslands and heritage dry stone walls are also being avoided or minimised as much as possible.

“Despite the challenges and complexities, the Melbourne Water and John Holland project team need to be complimented on the adaptive construction management approach to the project, which sees it continue towards scheduled completion prior to peak demand expected this coming summer.”

Land management

Assisting Mr Clark and Melbourne Water on the project is site-based Project Manager, Adrian Cullen. Land access and management have been a key focus for Mr Cullen on the project.

“Being in the outer-western suburbs, some of the fastest growing suburbs in Melbourne and Australia, we’re also dealing with residential developers to manage conflicts in future development plans,” said Mr Cullen.

“There are other infrastructure upgrades to services needed for the future as well, such as water, gas, electricity and communications.

“This is in addition to dealing with the sub-divisions. It’s been quite a complex project in that aspect.”

As with most pipeline projects currently under construction across Australia, liaison with landholders and various stakeholders has occurred throughout the project.

“Land access has progressively been going on for over 12 months and there’s been a lot of work done consulting with landowners, Councils and State Government departments as well,” said Mr Cullen.

“Given that a large portion of the watermain is located within road reserves, traffic management and minimising impacts to the community has been a key focus on the project.”

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