At a glance


Western Australia, Australia

Type of project



Western Australian Water Corporation

Contract type

Design and Construct



Providing local communities with a high quality water supply

The Mundaring Water Treatment Plant (MWTP) involved construction of a new water treatment plant, a pump station and various pipelines.

Water from the plant is produced to standards specified by the Water Corporation, who use it for the Goldfields and Agricultural Water Supply Scheme.

The water treatment plant site is located at the Department of Environment and Conservation (DEC) Perth Hills District Office and Depot site, situated off Mundaring Weir Road.

Western Australia’s first public private partnership, ATJV and Helena Water will fund, design, construct and operate the plant for 35 years.

Multiplex’s undertaking included new buildings, treatment systems (pre-treatment, filtration, chloramination, stabilisation and flouridation) plant, equipment and other facilities required to meet water quality requirements.

Multiplex shone in the competitive process put forward by the Water Corporation, thanks to its extensive experience and success in delivering various water infrastructure projects.

  • Design: GHD
  • Architect: Woodheads (GHD)
  • Quantity Surveyor: RBB
  • Process / Mechanical / Electrical Consultant: Acciona
  • Environmental / Geotechnical: Golders

Project in numbers


kilometer pipeline


plant capacity