Tunnel Infrastructure WTP by Ryan Davis – Perspective from the Project Manager

December 8, 2020

Another Hydroflux Tunnel infrastructure Water Treatment Plant (WTP) in Sydney has been commissioned and handed over.

The entire Wastewater Treatment Plant

Hydroflux Industrial’s Project Manager Ryan Davis worked closely on this project:

“The effluent water treatment plant is complete, and everyone is really happy with the results. I’d like to thank everyone that was involved in building this high-quality infrastructure project”.

Tunnelling infrastructure is necessary for many Australian cities to meet their future transport needs. During construction, water accumulates within the tunnel from groundwater sources interrupted by the excavations and from the processes of tunnelling itself.

Tunnel effluent primarily consists of groundwater, which contains heavy metals, particularly Iron which can cause discoloration in the receiving water if it is not removed. Other than the Iron ground water can also contain high quantities of natural impurities and in some instances man-made pollutants that are a legacy from past industrial activities at the surface.

This new Sydney infrastructure WTP was designed to treat tunnel effluent which consists of groundwater, wash water and run-off collected in the tunnel drainage system. Tunnel effluent is pumped to the WTP and then treated to the quality required by the Environment Protection Authority before being released into a local waterbody.

The Treatment Process consists of:

  • Inlet water quality monitoring
  • Screening
  • Balancing & Aeration
  • Chemical Pre-Conditioning (pH correction & coagulation)
  • Solids removal via Dissolved Air Flotation using a Hydroflux HyDAF
  • Advanced Multimedia Filtration
  • Outlet water quality monitoring

The residuals produced are dewatered to a dry and spadable cake via a HUBER QPRESS.

The Multimedia Filtration set-up.

After the raw tunnel effluent has been aerated in the balance tank the iron precipitates, discolouring the water brown. After further chemical pre-conditioning (pH correction and coagulation) and solids removal via Dissolved Air Floatation (DAF) the effluent has much of the brown colour removed. After dissolved metal precipitation and advanced Multimedia Filtration the water quality is suitable for discharge to the adjoining waterway.

Photo showing (left) raw effluent, (middle) post primary treatment -dissolved air flotation DAF and (right) post -tertiary treatment -multi-media filtration – AMMF.

“This is another example of critical infrastructure provided by Hydroflux to help support communities and drive growth around Australia.” Said Ryan Davis.

Up Next