Freshwater in farming regions is high in faecal bacteria, an independent report by the Ministry for the Environment has revealed.
Polluted waterways, greenhouse gas emissions and urban growth and pollution have been highlighted in the Environment Aotearoa 2019 report, which also says there's been a lack of data collection.
Is our water clean enough?
Scott Larned, chief freshwater scientist at the National Institute of Water and Atmospheric Research (NIWA), says water quality in New Zealand is a major problem.
"At many of these sites some variables are at desirable levels or improving," but only slowly, "while others are simultaneously at undesirable levels or degrading."
Rivers, lakes and groundwater in farming areas have highly elevated levels of nitrogen, phosphorus, fine sediment and faecal bacteria, compared to levels in native-forest areas, the report says. And many urban streams have been contaminated with heavy metals.
This is backed by NIWA research showing high nitrogen concentrations and levels of faecal bacteria occur at coastal sites where rivers spill into tidal estuaries.
"The same national scale pattern has been reported for more than 20 years, which indicates that the Government's current reforms of the way we manage our freshwaters needs to be bold if they are to meet New Zealanders' expectations," Dr Larned said.
"Coastal water quality monitoring is a recent initiative for most councils and data are scarce, but results to date indicate that nitrogen and faecal bacteria concentrations are elevated in coastal waters near river mouths."
A nationwide poll conducted in December for Fish and Game found 80 percent of New Zealanders want stricter rules to protect our rivers, lakes and waterways from pollution.
NIWA chief scientist for coasts and oceans Dr Barb Hayden said it was good the report linked the terrestrial, freshwater and marine domains because they are "intrinsically connected".
"This is particularly true in estuaries and near-shore coastal environments, which provide food, nurseries for fish, and cultural and recreational benefits to us all."
Biodiversity and climate change
The lack of data around biodiversity is a concern, the report says, with only about 20 percent of our species identified and documented.
"There's an urgent need to document what exists, particularly in the case of insects, microplants such as liverworts, lichens and mosses, and marine life," Ken Hughey, chief science advisor at the Department of Conservation, said.
He said these species are important because they "underpin what makes New Zealand's biodiversity so special, alongside charismatic megafauna like the Maui dolphin and kākāpō".
Dr Hughey said getting data on the remaining 80 percent of New Zealand species - some of which are "lower-profile" - will "give us a much better idea of strategies to protect our biodiversity".
And on climate change, the main issues raised in the report were around how biodiversity is being affected and how natural resources should be managed.
Ecosystems and climate change researcher Anne-Gaelle Ausseil from Manaaki Whenua Landcare Research said gaps in the data "show how much more progress is still needed" in that area.
Dr Ausseil, who was part of the senior science team for the report, said stronger collaborations with the Intergovernmental Panel on Climate Change (IPCC) and other global initiatives "should ensure positive outcomes for both biodiversity and climate".
Minister for Climate Change James Shaw said the report underlines the importance of the Government's plan of action around climate change.
"The introduction of climate change legislation, establishing an independent climate change commission to guide emissions reductions, and the just transition to a low emissions economy are vital, as the evidence in this report shows."
The Ministry for the Environment has appointed an expert panel to assess climate change amid Greenpeace claims New Zealand's emission levels are "disturbing".