Ngā puna wai Water Supply
Greater Wellington’s Water Supply activities achieved 91 percent of their 11 performance measures this year. The 1 measure not achieved came within 2 percent of the target.
What we deliver for the region’s water supply
Water is a fundamental need for our communities, so we will continue supplying a sustainable, clean, and safe drinking water supply. Respecting the environment and tackling climate change are a key consideration in how this is achieved.
Greater Wellington is responsible for collecting, treating and distributing safe and healthy drinking water to Wellington, Hutt, Upper Hutt and Porirua City Councils. This work is carried out for Greater Wellington by Wellington Water Limited (WWL), a joint council-owned water management company. City and district councils are responsible for the distribution for water to households and businesses through their own networks. Providing the bulk water supply to the city councils involves managing a network of infrastructure, ensuring safe, high-quality, secure, and reliable water sources, and that our freshwater is sustainable.
Te Mārua Water Treatment Plant Capacity Upgrade Project
The Te Mārua Water Treatment Plant is a critical infrastructure asset to the region, supplying approximately half of the region’s drinking water supply. To support future growth and reduce the risk of an acute water shortage during summer, upgrades to the Te Mārua Water Treatment Plant have been under construction since February 2023.
Greater Wellington brought forward investment in these upgrades following the heightened risk of an acute water shortage and tighter restrictions in summer 2023/24. This has enabled Wellington Water to complete the first two stages of the upgrades ahead of time, allowing the plant to treat and supply an additional 20 million litres of drinking water per day (MLD). This significantly reduced the risk of tighter water restrictions in the 2024/25 summer.
Works completed in June 2025 increased the Plant’s capacity from 80 MLD before the project to 120 MLD over a day, with instantaneous flows up to 140 MLD. This enables the Plant to supply more water to meet peak daily demand.
Local Water Done Well
Greater Wellington councillors have unanimously confirmed their commitment to proceeding with a combined regional approach to developing a water services delivery plan with mana whenua and participating city councils.
In 2024 the Government introduced the Local Government (Water Services Preliminary Arrangements) Act 2024, which established the Local Water Done Well framework. The framework is designed to address long-standing challenges in water infrastructure management and delivery across the country.
Council formally agreed to jointly establish and co-own a new waters services Council-controlled organisation (CCO) for three waters, together with Wellington City Council, Porirua City Council, Hutt City Council and Upper Hutt City Council and mana whenua partners Ngāti Toa Rangatira and Taranaki Whānui ki Te Upoko o Te Ika.
The intention is to transfer Greater Wellington’s assets, debt, liabilities and services in relation to bulk water supply to the new jointly owned CCO on or by transition after 1 July 2026.