Our Freshwater 2026 shows how central groundwater is to daily life, supplying drinking water to nearly half of New Zealanders and around 80 percent of everyday flow in many rivers.
The report by the Ministry for the Environment and Stats NZ is the latest in the national environmental reporting series produced under the Environmental Reporting Act 2015. The last freshwater report was released in 2023.
Our Freshwater 2026 shows how land use, climate change and more frequent extreme weather events are combining to put pressure on freshwater. The impacts of this are visible across rivers, lakes, wetlands and estuaries, and in the water many communities rely on every day.
"Freshwater doesn’t operate in separate parts – it’s one connected system. Groundwater is the part we don’t see that links the whole system together," said Dr Alison Collins, Chief Departmental Science Adviser, Ministry for the Environment.
"Many rivers depend on groundwater to keep flowing day-to-day. But while it supplies rivers continuously, groundwater responds slowly to change. It behaves a bit like a long-term savings account – the system holds onto what goes in. Pollution that reaches groundwater can take years to decades to flush out. That’s why early, targeted action matters."
What happens on land leaves a lasting imprint. Nutrients, sediment and contaminants from farming, urban life, existing urban landscapes, and other land uses can wash into waterways – and can also seep into groundwater.
This is visible in national monitoring. Between 2019 and 2024, E. coli was detected at least once in 45 percent of 998 monitored groundwater sites highlighting how easily contaminants can move from the land into groundwater stores.
The report shows why storms can be problematic for freshwater. Extreme rainfall events can pick up and carry pollution and sediment, moving a lot of it very quickly.
"Climate change is intensifying pressure on an already stressed system," Dr Collins said.
"More intense storms, longer dry spells and hotter temperatures make freshwater less stable and less predictable."
"Targeted land actions such as better nutrient management, fencing waterways and riparian planting reduce contaminant loads – especially during storms," Dr Collins said.
"In our towns and cities, councils are using nature-based solutions to slow down stormwater – rain gardens, swales and wetlands help the water soak in, filter harmful chemicals and germs, and lower the risk of pipes overflowing."
"Scaling up what works is how we protect freshwater, communities and taonga species."
Our Freshwater 2026 includes new updates to national freshwater indicators and strengthens the evidence on groundwater connections, extreme events and long-term system risk.
Our Freshwater 2026 is the Ministry for the Environment and Stats NZ’s latest synthesis of freshwater health and trends across Aotearoa New Zealand. It reports on 15 national indicators; all but three are updated since Our Freshwater 2023.
The report places stronger emphasis on:
Key findings include:
Practical actions people can take, include: