What is sewer mining?

Sewer mining is the process of extracting, treating and using wastewater before it reaches a wastewater treatment plant. Sewer mining has the potential to recover nutrients and energy.

Water recycled through sewer mining can be used for purposes such as:

  • irrigating sporting fields, golf courses, parks and gardens and
  • in commercial building applications.  

This process typically involves:

  • extracting raw wastewater from the sewer main upstream of a wastewater treatment plant;
  • delivering the extracted raw wastewater to a decentralised treatment facility;
  • treating it to ‘fit for purpose’ quality;
  • delivering recycled water to the end user; and
  • managing residuals.

Water from sewer mining is not suitable for scheme water uses including drinking, cooking, bathing or filling of swimming pools or spas.

There are various types of treatment technologies available for sewer mining, the most common being membrane bio-reactor and multiple water reuse. The level of treatment required for sewer mining schemes is informed by the end use and regulated by the Department of Health (DoH). The Guidelines for the Non-Potable Uses of Recycled Water in Western Australia, available from the Department of Health, provide more information in this regard.

Our involvement in sewer mining schemes

Potential sewer mining operators may receive some early assistance from Water Corporation, to assist with concept evaluation and development, such as:

  • technical characteristics of a wastewater scheme
  • wastewater catchment profile
  • existing and planned recycling commitments; and
  • guidance on the application and assessment process.

We cannot guarantee the quantity or quality of wastewater for a sewer mining scheme. This may be the result of emergencies, unforeseen wastewater flow fluctuations. We may need to interrupt