Three Waters



Too often we see network failures like burst pipes and sewage spills – signs our wastewater system is in trouble.

The Government’s reform proposals are designed to ensure our wastewater networks are future-proofed and protect our environment.

Research from the Three Waters Review has revealed our communities are facing rising costs to grow, maintain and upgrade wastewater networks to meet community expectations and environmental standards. The research published below shows that more than half of the wastewater treatment plants in the country need to be reconsented over the next 10 years. These upgrades are expected to be significant and very costly due to increased community and cultural expectations since treatment plants were first consented decades ago.

While these treatment plants are significant and expensive investments for communities, the greatest costs to communities associated with these services lie in the underground pipes, or infrastructure.


A sink filled with used water, brown with soapy bubbles on top.

Wastewater networks pull away used water from our kitchens and bathrooms.

GHD-Boffa Miskell Wastewater Reports

The Department of Internal Affairs commissioned four reports from GHD and Boffa Miskell as part of the Three Waters Review. The reports give a national-level assessment of the state of New Zealand’s local authority wastewater services. Find out more about these reports below.