Improvements to our wastewater network are necessary to keep pace with the needs of Auckland’s growing population and businesses. These projects are focused on ensuring that we have the most efficient system for carrying wastewater for treatment so that it can be returned safely to the environment. This is essential for maintaining public health, reducing the risk of polluted overflows into the environment, and also that we can reuse this precious resource.

In most cases, wastewater projects do no disrupt services to our business or residential customers. However, the works often require excavation to replace or repair pipelines and we work closely with local communities in planning these projects to keep disruption to a minimum.

Sewer separation

Sewer separation is one of our key initiatives and is important in reducing the levels of polluted water entering our harbours. We are currently separating the combined wastewater networks in various areas of the city into separate sewerage and storm-water networks.

For further information visit the Environment and conservation section, or watch our video on Keeping our harbours clean.

Wastewater pipe renewals and rehabilitation

These projects extend the life of existing wastewater systems by replacing and relining them.

Metrowater rehabilitate pipe networks using 'trench-less technology'. We reline the pipes with a resin-impregnated sock and fix the resin and sock in place by pumping hot water through the pipe system being rehabilitated. This means customers are not inconvenienced by open trenches and other associated disruptions such as potential traffic delays and hazards.

CCTV inspections

Metrowater undertakes Closed Circuit Television Inspections of our wastewater networks to ensure that critical pipes are in good working order and to determine which pipes need rehabilitation.

Smoke testing
Smoke testing of wastewater pipes involves using a small machine to blow smoke into your sewer pipe. This smoke is white, cold, non-toxic, non-irritant and completely harmless. It is similar to smoke currently used in theatre productions.

It allows us to see if stormwater can enter your wastewater system. If the system is working properly, the smoke will be released from the terminal vent and other ventilation points located on buildings. However, if the smoke discharges from downpipes, it indicates there is a problem with the system that will need further investigation.