Conservationists alarmed by new report into New Zealand's freshwater

Conservation advocates say a new report confirms the country's freshwater is at breaking point.

The Ministry for the Environment and StatsNZ's Our Freshwater 2026 report highlighted the worsening quality of groundwater, rivers and lakes, including increasing levels of nitrates, E.coli levels breaching the legal limit, and nearly half of the country's river network being unsafe for swimming.

Around half (45 percent) of the 998 groundwater monitoring sites tested had E. coli concentrations above the legal limit for drinking water on at least one occasion between 2019 and 2024, and modelling estimated 44 percent of New Zealand's total river length was unsuitable for activities like swimming due to faecal contamination.

Among other indicators painting a worrying picture the report said glaciers, which acted as major freshwater reservoirs for rivers and groundwater, were rapidly retreating - decreasing 42 percent between 2005 and 2023. Invasive species were having a direct impact on native ecosystems and even hydroelectric power generation. Wetlands continued to be lost or degraded, despite only 10 percent of historical wetland areas remaining.

Other issues exacerbated by climate change included rising sea levels risking saltwater contamination of coastal groundwater, increased extreme rainfall amplifying run off and erosion, landslides sending more sediment into streams and rivers, and increased droughts predicted for the country's north, the report said.

Forest and Bird spokesperson Nicky Snoyink said the environment needed action, not another report tracking declining water quality.

"We've seen report after report that highlights this stuff - this one sheets home that our freshwater is at breaking point."

Ministry for the Environment chief departmental science adviser Dr Alison Collins said the report underscored the importance of freshwater and the interconnected nature of ground and surface water.

The report was not intended to provide policy advice, but to supply independent evidence to support decision-making, showing where pressures were building and where progress was occurring, she said.

Over the longer term, nitrogen was one of the biggest pressures, Collins said.

Nitrogen worsened at about 53 percent of lake sites, while nitrogen in groundwater worsened at 39 percent of sites.

Rivers showed a more mixed trend, with nitrogen very likely worsening at 31 percent of monitored river sites and very likely improving at 30 percent between 2005 and 2024, Collins said.

Another concern was ecosystem health, with 54 percent of river length showing moderate or severe organic pollution and 63 percent of our lakes in poor or very poor health.

In the short term, the ministry was concerned about E.coli, cryptosporidium, and other bacteria and pathogens that could cause gastrointestinal illnesses, she said.

While the report pointed to pressures from land use, it was not just the farming sector that was responsible, Collins said.

"In Canterbury, for example, urbanisation around Rolleston and Prebbleton and Lincoln has meant there's more impermeable surfaces which increase runoff, and more stormwater and wastewater pressure," she said.

The report identified critical knowledge gaps, including a lack of data on how much water was being taken from rivers and lakes, when and for what purpose.

The information was available on how much water was consented for, but not how much was actually used.

"It would be helpful if we knew more - it would give us a much better understanding of risks and low flow in the system," Collins said.

Other areas where information was lacking included on emerging contaminants like pharmaceuticals, stimulants, PFAS (per- and polyfluoroalkyl substances, dubbed forever chemicals for their persistence in the environment and human body) and microplastics.

"Evidence gaps include pathways from land to freshwater, long-term impacts on ecosystems and drinking water, the scale of pesticide residues following heavy rainfall and sowing and interactions with antimicrobial resistance," the report stated.

University of Waikato associate professor Nicholas Ling said the report had some positive signs, but they were few and far between.

Climate change was taking a toll in longer dry spells and more frequent heavy rainfall, but also in increased bacteria and harmful algae, that reproduced far faster with each degree of increased temperature, he said.

Ling said he wanted to see improved co-ordination between those caring for water.

"There are so many agencies that have jurisdiction in freshwater from the Ministry of the Environment, the EPA [Environmental Protection Authority], regional councils and DOC [Department of Conservation] and Fish and Game - there's a whole lot of organisations, but there's no co-ordinated effort."

It was entirely possible to turn things around, and other countries who had experienced similar declines were making huge gains in their freshwater quality, he said.

"In places like the UK, otters have returned to every county and there's loads of fish species you can catch in the Thames now.

"They've made these striking improvements in freshwater quality, which demonstrates it is possible to reverse the decline, but we're not seeing that in this country despite our clean green image."

While not everyone was as concerned as they should be at the rate of indigenous freshwater fish threatened with extinction - 89 percent, among the highest in the world - freshwater quality affected everyone, Ling said.

"It's our drinking water, it's our recreational activities. Two-thirds of our lakes are unsafe to recreate in now because their water quality is poor, almost half of our rivers are unsafe to swim in.

"A lot of our drinking water comes from rivers or lakes or groundwater and that's declining - that's a real threat to both our economy and to people's health," Ling said.

New Zealand had experienced high levels of land use intensification, such as increased use of fertilisers and irrigation, increased stocking rates and soil draining, which had also led to increased fertiliser run off and contaminants leaching into waterways, the report found.

Irrigated land had increased by 99 percent between 2002 and 2022 while land used for dairy farming had almost tripled over the same period.

The number of dairy cattle increased 71 percent from 3.4 million to 5.9 million between 1990 and 2023, peaking at 6.7 million in 2014.

Primary food production accounted for 74 percent of allocated freshwater use. Between 2018 to 2022, the dairy industry used about 2.5 billion cubic metres of surface water a year, around 93 percent for irrigation, the report said.

Green Party environment spokesperson Lan Pham said she hoped the report served as a wake-up call for the government.

"They cannot continue this slash and burn approach when it comes to environmental protection, because if they do the environmental outcomes - like we've seen in this report - are not going to lie.

"Things are just going to get worse, and unfortunately, it will be Kiwis who pick up the cost of that."

She said the figures on the country's unsafe rivers, or groundwater that was unsafe to drink were "entirely unacceptable."

And she warned moves to fold the Ministry for the Environment into a new mega ministry would see even fewer protections for water.

"The Ministry for the Environment has been around for 40 years now and that's because Kiwis decided the environment was so important that they wanted a dedicated ministry.

"Eroding that and all the removals of freshwater protection the government is doing is simply going to make the situation worse rather than better."

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