Breathe easier, but be careful where you drink from: the state of the environment

The latest update on New Zealand's environment shows people can breathe a little easier, but a substantial proportion of groundwater is failing drinking standards.

The country's top environment official said the report shows "very real risks to people" from problems such as unsafe drinking water and worsened floods from climate change.

But Secretary for the Environment James Palmer said Our Environment 2025 also shows people can fix environmental degradation.

"Our choices matter," Palmer said.

"Overall we are seeing a mixed bag, and while there are considerable causes for concern, the data does suggest there is cause for optimism because some of the things we've been doing to reduce our impact are really starting to bear fruit.

"We are seeing improvements in coastal and estuarine water quality, we are seeing reduced air pollution and we are seeing those greenhouse gases starting to come down."

The report is the most comprehensive update on New Zealand's environment, pulling together three years' worth of six-monthly updates by the Ministry for the Environment and Stats NZ on air, atmosphere and climate, freshwater, land, and marine areas.

One of the areas of concern was biodiversity, with many species in serious trouble.

Greenpeace Aotearoa executive director Russel Norman said the report documented the rapid and dramatic decline of nature.

"There is only a single species of indigenous bat that is NOT at risk of extinction; only a single species of frog NOT at risk of extinction; just 22% of birds are safe from extinction; over 2,000kg of protected corals pulled up by commercial fishing nets. And on and on the list goes," he said.

"We are in a biodiversity crash dive."

Palmer said although the stocktake showed the country had "started to turn the corner in meaningful ways", some indicators were worrying.

"There is cause for ongoing attention and concern," he said.

"We are continuing to see decline of many of our indigenous plant and animal species.

"I think what we see there is the vulnerability of our indigenous ecosystems to the pressures of human occupation and I think in that area we should remain concerned about whether we are doing enough, and it is in those areas that there is considerable room for improvement.

"We do have severe issues as a country with invasive predators and weed species."

He singled out wild pine for its rapid spread. "That is one invasive plant species that is marching across our landscape, and there are others."

On the good side, lung-damaging traffic pollution has been improving in most cities as a result of cleaner cars and people switching from wood and coal to electric household heaters and heat pumps, thanks to rising government standards on tailpipe emissions and consumer choices.

Both the population and the economy have been able to grow while shrinking greenhouse gas emissions, which have begun to fall in all sectors of the economy.

Waste to landfill has reduced, while remaining high by OECD standards.

The report highlights examples of community planting and restoration efforts - from central Auckland to remote Tairawhiti - that have reduced flood risks from heavy rain and protected the water in streams, rivers and coasts from pollution.

Major lowlights included the ongoing decline of native species, the spread of pests including wilding pine and unsafe levels of contamination in some groundwater used for drinking water.

It said a significant proportion of groundwater has accumulated excess nitrate due to human activities and even some deep aquifers (deeper than 30m) were not safe for supplying drinking water unless the water had been treated for nitrate. Excess nitrate is typically a result of intensive farming above ground. It can build up over time in underground water supplies, so it can keep increasing even when activities above ground are creating less.

Bacteria was also at problem levels in some places. Forty-six percent of the country's 1007 groundwater monitoring sites tested failed to meet the drinking water standard for E. coli on at least one occasion between 2019 and 2024.

Meanwhile, Palmer said the impacts of climate change were quickly becoming real.

"Between 1909 and the present, average annual temperatures in New Zealand have increased by 1.26 degrees Celsius, so we are seeing the effect of climate change on temperatures, but we also see it in the frequency and intensity of severe weather, whether that be droughts or extreme rainfall events.

"We are well and truly now seeing the impacts of climate change, and there will be long lag periods, so we have this change in climate with us at least for the foreseeable future and it will take an enormous amount of global effort to reduce that."

Here's some of what the report said about drinking water, air pollution, fisheries, landfill waste and more:

Waste

The good:

• Waste to landfill per capita dropped 11 percent in the last few years.

The bad:

• Newly-included data show New Zealanders sent a lot of waste to municipal landfills each year between 2021 and 2023, compared with other similar countries.

Pests

The bad:

• The total cost of introduced pests to New Zealand was estimated at $9.2 billion in 2019/20, including primary sector losses of $4.3 billion.
• The area covered by wilding pines was estimated to be growing at 90,000ha per annum.

Air quality

The good:

• New Zealand has good air quality compared to most OECD countries.
• New evidence shows motor vehicle engine and fuel improvements continue to reduce air pollution.
• That's despite New Zealanders collectively traveling more kilometres each year, a growing vehicle fleet and steady growth in the proportion of diesel vehicles.
• The number of electric vehicles has also grown, nearly doubling from 2022 to 2024, contributing to cleaner air.
• New data show burning wood and coal for home heating (a major source of air pollution) continues to decline in favour of heat pumps and electric heaters.
• Average readings of nitrogen dioxide - a dangerous air pollutant - were improving at 99 of 114 sites in the decade to 2023.

The bad:

• Nitrogen dioxide concentrations from road traffic were still going over safe breathing levels, as were some other air pollutants.
• In 2019, human-made air pollution was a factor in 3239 premature deaths, 13,237 hospitalizations and 12,653 cases of childhood asthma.

Fish and oceans

The good:

• Water around coasts and estuaries was getting less polluted by nitrogen and phosphorous (which is found in fertilisers used in agriculture) in more places than water was getting more polluted.
• It's a similar story for disease-causing bacteria. Faecal coliform levels were improving at 50 percent of coastal and estuary sites and worsening at 24 percent.
• The area of sea floor bottom-trawled each year is decreasing.

The bad:

• New evidence shows marine heatwaves have become more frequent, more intense and longer lasting in some parts of the ocean and this is expected to get worse.
• Sea level rise is accelerating around New Zealand and the oceans are getting warmer and more acidic.
• Recreational fisheries declined between 2017/18 and 2022/23, particularly in the north of the country.
• More species of native marine mammals are decreasing in population than increasing.

The mixed:

• Most native marine bird species (82 of 90) are threatened with extinction or at risk of becoming threatened. However, the majority have stable or increasing populations (compared with 27 percent which are decreasing).

Climate

The good:

• 2022 total greenhouse gas emissions were their lowest since 1999, but still higher than 1990.

All sectors (except Tokelau, which New Zealand includes in its count) reduced emissions between 2021 and 2022.

• Extreme wind seems to be decreasing across most of New Zealand.

The bad:

• Updates to climate monitoring showed the south of New Zealand is becoming wetter, and the north and east are becoming drier - meaning already wet or dry places are tending to get wetter or drier.
• New evidence confirms extreme weather events are becoming more frequent and severe due to climate change from human activities.
• The country's annual average temperature increased 1.26 degrees Celsius between 1909 and 2022, and eight of the 10 warmest years on record happened between 2013 and 2022.
• New Zealand has high emissions per capita by OECD standards because high per capita farming emissions are not offset by high renewable energy generation, said the ministry's Chief Science Advisor, Dr Alison Collins.
• We are starting to see multiple severe weather events happening at the same time or in the same place, or both, like the atmospheric river that delivered record rainfall to Auckland in January 2023, which was closely followed by Cyclone Gabrielle in February 2023.
• The estimated damage to the food and fibre sector alone from Cyclone Gabrielle was between $700 million and $1.1 billion in recovery costs.

Lakes and rivers

The mixed:

- A new model for lake water quality confirms that almost half of the country's lakes are in poor health. However, unlike the previous model, it predicts that most of the remaining lakes are in good health, rather than average.

The bad:

• Models estimated 45 percent of the country's total river length was not suitable for swimming because of the Campylobacter infection risk.
• In 2023 there were 388 cases of campylobacteriosis, 135 of giardiasis, 106 of cryptosporidiosis, 102 of salmonellosis and 138 of Escherichia coli infection where the sick person reported contact with rivers, lakes or the sea.

Drinking Water

The good:

• Groundwaters in most parts of the country comply with drinking water standards.

The bad:

• A significant proportion of groundwater has accumulated excess nitrate.
• Twelve percent of groundwater sites monitored failed to meet drinking standard for nitrate on at least one occasion between 2019 and 2024.
• Forty-six percent of groundwater sites monitored failed to meet the drinking water standard for E. coli on at least one occasion.
• Even some deep aquifers (30m plus) have been contaminated with bacteria.
• Of the 11,026 (pre-treated) samples from water supply bores tested for E. coli, six percent failed to meet the drinking water standard.
• Thirty-three percent of the 326 water samples from springs also failed the drinking water standard.
• The country has had at least 49 drinking water illness outbreaks since 1980, including the 2016 campylobacteriosis outbreak in Havelock North, which made an estimated 6000-8000 people ill, hospitalised 42 people, and led to at least four deaths.

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