Tunnel Dewatering Systems: Sydney Metro Northwest

NRT Infrastructure Joint Venture and Transport for New South Wales

Sydney, New South Wales, Australia

Sydney Metro first tunnel track requires approval
Epping to Chatswood Rail Line 33k V Cable cropped
Sydney Metro NW main PS image cropped

Diona installed tunnel dewatering systems as one of many various contracts covering electrical, water and wastewater services for the NRT Infrastructure Joint Venture (NRTI JV) to support the Sydney Metro Northwest (SMN) project, Australia’s largest public transport project.

Diona installed tunnel dewatering systems as one of many various contracts covering electrical, water and wastewater services for the NRT Infrastructure Joint Venture (NRTI JV) to support the Sydney Metro Northwest (SMN) project, Australia’s largest public transport project.

Sydney Metro is a new world-class railway for Sydney. Services started in the city’s north west from Rouse Hill to Chatswood in May 2019 on Australia’s first fully-automated railway, with 13 metro stations and 4,000 new commuter car parking spaces.

A new generation of metro trains runs every four minutes in the peak in each direction. Customers don’t need a timetable, they’ll just turn up and go.

Diona installed tunnel dewatering systems to collect and convey water to the existing Epping to Chatswood Rail Link (ECRL) drainage system for discharge to the Lady Game Drive Water Treatment Facility.

As part of the tunnel works, dewatering systems were required to remove water from the tunnel and ensure there was no future disruption to the rail service.

The system, is made up of sumps at stations and low points of the tunnel, and a pipe network to collect and convey water to the existing ECRL drainage system.


Diona carried out the following installation works:

  • 14 pump installations at various sump pump locations within the tunnel
  • Mechanical requirements – pipework rising mains, valves and fittings
  • Electrical communication requirements – junction box, instrument panels, water level transmitters, valve position indicators, remote I/Os at each sump.