Greater Western Water

Overview

Greater Western Water was formed on 1 July 2021 through the merger of City West Water and Western Water. The combined entity now serves over one million people across Melbourne’s western suburbs and surrounding peri-urban and regional communities. It is the newest of the three retail water companies serving metropolitan Melbourne.

History and Formation

City West Water was established in 1995 as part of Melbourne’s water industry restructure, providing services to the inner-west and western suburbs of Melbourne. Western Water operated as a separate regional authority, managing water and sewerage services for communities to the north-west of Melbourne, including Sunbury, Melton, Bacchus Marsh, and surrounding rural areas.

The Victorian Government merged the two utilities in 2021 to create a single entity better positioned to manage the rapid population growth and urban development occurring across Melbourne’s western corridor. The merger was intended to improve service coordination, infrastructure planning, and operational efficiency across a region experiencing some of the fastest growth rates in Australia.

Service Area

Greater Western Water’s service area extends from inner Melbourne suburbs such as Footscray, Williamstown, and Yarraville through to outer growth areas including Melton, Rockbank, and Aintree, and further to regional towns like Gisborne, Romsey, Lancefield, and Bacchus Marsh. The area spans approximately 3,700 square kilometres and covers parts of 11 local government areas.

The western growth corridor is one of the most significant urban expansion areas in Australia, with major new housing estates being developed across suburbs like Tarneit, Truganina, Wyndham Vale, and Rockbank. This growth drives substantial investment in new water and sewerage infrastructure.

Water Supply

Water supplied to the metropolitan portion of the service area comes primarily from Melbourne Water’s wholesale supply, sourced from the city’s protected catchment reservoirs and treated at Melbourne Water’s water treatment plants. The regional portion of the service area draws from a combination of Melbourne Water supply and local sources, including the Merrimu and Rosslynne reservoirs.

Greater Western Water operates several smaller local water treatment plants that serve regional communities outside the Melbourne Water supply network. These facilities treat water from local surface and groundwater sources.

Distribution Network

The combined network includes approximately 7,600 kilometres of water mains and 6,800 kilometres of sewer mains. The system also comprises over 80 reservoirs and tanks, along with numerous pump stations. Managing this network across such a large and varied service area, from dense inner-urban areas to semi-rural towns, presents unique operational challenges.

Water Quality

Greater Western Water monitors water quality throughout its distribution network, ensuring compliance with the Australian Drinking Water Guidelines. For areas supplied from the Melbourne Water system, customers benefit from the high-quality, low-hardness water sourced from protected catchments. Regional areas supplied from local sources may have different water quality profiles, reflecting the characteristics of local catchments and groundwater.

The utility conducts routine testing at customer taps, reservoirs, and throughout the pipe network, monitoring for microbial indicators, disinfectant residuals, turbidity, pH, and chemical parameters. Annual water quality reports are published and accessible to customers.

Recent Projects

As a newly formed entity, Greater Western Water has focused on integrating the operations and systems of its predecessor organisations. Significant capital investment is directed toward trunk water and sewer infrastructure in Melbourne’s western growth areas. The utility has also invested in recycled water schemes, including the Western Irrigation Network, which supplies recycled water to agricultural users. Sustainability initiatives, including energy recovery from wastewater and solar power installations, are part of the organisation’s operational strategy.