Regulation of Wellington’s water services
The Commerce Commission has introduced additional economic regulation for Tiaki Wai to improve transparency, accountability, and outcomes for Wellington consumers.
Our role
On 1 July 2026, Tiaki Wai assumed responsibility for delivering water services in the Wellington metropolitan area and became subject to our full economic regulatory regime.
Our focus is protecting the interests of consumers now, and in the long-term. We consider that there are matters that need to be addressed immediately by Tiaki Wai to enable it to restore confidence to Wellingtonians as quickly as possible.
Additional economic regulation for Tiaki Wai
We have made final decisions on additional information disclosure (ID) requirements for Tiaki Wai. These requirements are designed to establish a clear performance baseline. Good decisions depend on good information, and a clear performance baseline helps understand where performance is today and where it needs to improve.
The additional ID requirements build on and accelerate the sector-wide enduring ID regime introduced in 2026. They are intended to provide earlier transparency and further assurance in areas of highest risk. These areas are asset management, delivery, financial sustainability and non-financial performance.
Foundational information disclosure for Wellington Water
In October 2025 Wellington Water began publishing information about aspects of its performance, as specified by us. We monitored that Wellington Water disclosed the specified information and at the required time, analysed the information that is published, and shared some of our insights. The views we formed reinforced early concerns about data quality and other matters directly affecting planning, investment prioritisation and delivery. This led to our consideration of further economic regulation for Tiaki Wai.