Environment Minister is given proposal for tougher water quality standards

Environment Minister David Parker will consider tougher water quality standards which have been proposed to replace the standards National introduced last year, Radio NZ reported today.

The previous government was widely criticised for introducing standards for swimming which did not actually measure the health of lakes and rivers.

Mr Parker has been presented with the proposed National Policy Statement for freshwater management which was written by Fish and Game with input from Forest and Bird, the Environmental Defence Society and Greenpeace.

A key difference between the two sets of standards is that the proposed Freshwater National Policy Statement would account for the health of ecosystems, setting a bottom line which enables people to swim and collect food from rivers and lakes without getting sick.

Research from freshwater scientist Mike Joy was used for the proposal, which he said sets standards requiring measurements of more components of the water to give a much broader picture of what is happening in a catchment.

“What we had before was a National Policy Statement that talked all about ecosystem health, but then had no measures of ecosystem health and no requirement for meeting levels of ecosystem health,” he said.

The previous standards were introduced by former Environment Minister Nick Smith, who dismissed criticism of them as “junk science”.

But Dr Joy told Radio NZ those standards could not even achieve their own stated aims, and if the proposed measures were put in place there would be action on improving water quality.

Mr Parker declined to be interviewed on the matter, saying he had received various views on national water standards and would consider them.

But he said a report from the Land and Water Forum last week proved consensus could not be reached on different measures of water quality and the mandate now passed back to central government to tackle.

Source: Radio New Zealand



Land and Water Commission is proposed in response Govt’s request for advice

The Land and Water Forum has responded to a request from the Government for advice on preventing further decline in freshwater quality, managing sediment and controlling discharges of nitrogen to water.

The chair of the Land and Water Forum, Dr Hugh Logan, says New Zealand has made progress with water management reforms over the last five years bu further improvements are needed to halt decline.

“Local authorities and courts have been left to interpret and implement the emerging framework without any effective oversight, which has resulted in slowed and inconsistent implementation,” he said.

“More should be done, and a concerted effort at national level will be required to push forward robust and coordinated change in both urban and rural water management.”

The report makes a set of key recommendations.

* The Government should identify at-risk waterways and ensure plans are in place to halt further decline in quality. Action should be taken where nothing is happening.

* Loopholes in the Resource Management Act and National Policy Statement for Freshwater Management that make it possible for decline to continue should be closed and stronger measures taken to protect wetlands and outstanding waterbodies.

* Good Management Practice should be a national requirement for all, including for those managing urban waterways. A range of risky land practices should be controlled by national environmental standards. The “billion trees” programme holds great promise to improve water quality, including the prevention of erosion, and sediment entering waterways. There are many effective soil conservation and erosion control programmes already. The challenge is to scale them up and give them the resourcing, capability and regulatory backing to make them more effective.

* Stronger measures should be taken to address urban impacts on water quality, including regulating to prevent loss of streams and water pollution that can arise from urban building activity, vehicles, earthworks and sediment, and creating standard consent requirements for stormwater and wastewater management to ensure consistency around the country.

* Strong government leadership should be accompanied by a new Land and Water Commission to provide the coordination, resourcing and capability needed to make change.

The Forum has also suggested a staged process for addressing the allocation of nitrogen discharges. This involves limits on nitrogen in waterbodies and a short-term interim national framework allowing for transition from present practices.

This short-term approach would focus on over-allocated or at-risk catchments, manage down high dischargers and allow some flexibility for low dischargers, all with an overall environmental limit for the affected catchment.

Differing views on this are expressed in the report.

In the long term, iwi rights and interests should be addressed and the tools and system adapted to ensure land is used according to its ability to absorb any nutrient discharges coupled with the sensitivity of discharge in associated waterbodies, Dr Logan said.

“Our message to government is that councils and sector groups need strong central government leadership to address the complex issue of water quality, but what we have recommended will be a significant step forward in holding the line.”

The report is available HERE.

The Land and Water Forum represents more than 50 stakeholders consisting of industry groups, electricity generators, environmental and recreational NGOs, iwi, scientists, and other organisations with a stake in freshwater and land management. They are joined by central and local government active observers in developing a common direction through collaboration for freshwater management in New Zealand and provide advice to the Government.

Source: Land and Water Forum


Meeting the challenge of how NZ can reduce its agricultural emissions

The Royal Society of New Zealand, which is featuring its Annual Collection of Reviews on its website, this week is highlighting an article by Professor Hong Di FRSNZ and reviewing the potential of inhibiting ammonia oxidisers to significantly reduce nitrogen leaching and emissions in grazing pastures.

In the review article, ‘Ammonia oxidisers and their inhibition to reduce nitrogen losses in grazed grassland: a review‘, Professors Hong Di and Keith Cameron, from Lincoln University’s Centre for Soil and Environmental Research, discuss evidence from the laboratory, and in the field that demonstrates the efficacy of using nitrification inhibitors on pastures to reduce nitrogen leaching and emissions, as well as the roles played by different ammonia oxidisers.

The post says:

Nitrous oxide is a potent greenhouse gas with a long-term global warming potential 265–298 times that of carbon dioxide. The dominant source of nitrogen leaching and emissions is through animal excrement, with urine making up about 80% of the nitrogen released back into the pasture. About 70-80% of the nitrogen ingested by the animals is returned to the soil.

In New Zealand our dominant land use is pastoral agriculture. Animals graze the land throughout the year and a large chunk of our economy is built upon the agricultural industry. Accordingly, as New Zealand works towards becoming a low-emissions economy by 2050, finding effective ways to mitigate our agricultural emissions is a significant goal for society to work towards.

A single urination from a cow produces a nitrate deposit well beyond what can be utilised by plants. This surplus is prone to leaching after it is converted to nitrates, or lost as nitrous oxide gas. Most of the nitrate in animal urine is urea, which is swiftly converted to ammonia when deposited in the soil.

When the urea in the urine hits the surface of the ground, it becomes ammonium (NH4+) and is adsorbed into negatively charged soil cation surfaces, meaning there is minimal leaching in soils with good cation exchange capacity. However, in the soil the ammonium is oxidised quickly and a process known as nitrification occurs. As nitrate is an anion, it is not retained by the negatively charged soil particles, this means when drainage occurs it is leached out of the soil into groundwater or surface waters and will contribute to water contamination. Nitrous oxide is also produced as a byproduct through the denitrification process that occurs alongside the leaching.

If a nitrification inhibitor (NI) is applied to the soil to inhibit ammonia oxidation (the first step of the nitrification process), this can lower the concentrations of NO3 and nitrous oxide emissions caused by nitrification and denitrification.

Significant advances have been made in understanding the role of different ammonia oxidisers, including ammonia oxidising bacteria (AOB) and ammonia oxidising archaea (AOA). Archaea organisms are a relatively recent addition to our understanding of life on earth, and were discovered in the 1970s.

For well over a century it was believed that the nitrification process was mostly carried out by a bacteria called chemolithoautotrophic ammonia oxidising bacteria (meaning a type of microbe that utilises chemicals from the soil—in this case from ammonia, to make food for themselves).

But the discovery that archaea have the gene (amoA) to produce an important enzyme for oxidising ammonia (ammonia monooxygenase) has suggesed archaea may have more of an important role in nitrification than previously thought.

Populations of archaea carrying the ammonia oxidising gene were found to be much more abundant than the AOB in a range of soils, which suggested the archaea play a greater role in the oxidisation of ammonia than AOB. However, recent research targeting the amoA gene have shown that the abundance and activity of AOA and AOB fluctuate depending on the soil and environmental conditions.

Professor Di and his team conducted a study of intensively grazed New Zealand dairy pastures. They collected evidence that AOB grew significantly in number and activity in response to cattle urine, whereas the AOA did not appear to increase upon coming into contact with the urine.

Di’s research team also found that the AOB was significantly inhibited by applying a nitrate inhibitor called dicyandimide (DCD). In his review article Professor Di suggests that AOB and AOA prefer different soil and nitrogen conditions to grow and thrive in, with AOB playing a dominant role in grazed grassland and AOA in soils which are highly acidic or low in nitrate.

The nitrate inhibitor DCD is not currently in commercial use in New Zealand but has proven to effective in reducing nitrate leaching by 44–77% in a variety of rainfall conditions. DCD is awaiting the establishment of a standard for food by the UN Food and Agriculture association before it can be put into commercial use for New Zealand farmers.

The low toxicity of DCD make it an appealing environmental technology, which also has economic benefits of increasing nitrogen use efficiency and pasture dry matter yield. The review article suggests that future research should be investigated to deepen our understanding of the amoA gene, search for potential new nitrate inhibitors, and further understanding of how pasture responds.

Professor Hong Di is Professor of Soil and Environmental Science at Lincoln University and was made a Fellow of Royal Society Te Apārangi in 2016. His major research areas include nitrous oxide emissions, nitrate leaching and relationships with soil microbial communities in agroecosystems.

The review article ‘Ammonia oxidisers and their inhibition to reduce nitrogen losses in grazed grassland: a review’ has been published in Ngā Kete and is available free-to-access for a limited time at Taylor and Francis Online.

Source: Royal Society of New Zealand



Water quality framework needs improvement says LGNZ

Local Government New Zealand has released a discussion paper, Water 2050: Quality – Review of the framework for water quality,  which identifies three key issues for New Zealand’s framework for water quality and points to opportunities for change that could be a focus under the Government’s Three Waters Review.

LGNZ’s review of the regulatory framework considers how New Zealanders can better meet the quality of freshwater through environmental standards and protect the quality of their drinking water through specific health-related standards.

“The key finding from our review is that the regulatory framework for fresh water and drinking water does not take into account adequately the costs for communities to meet these standards,” says LGNZ President Dave Cull.

“There also needs to be better understanding of the costs and associated funding to meet these. Councils have competing priorities on water quality standards and we need to work with central government to agree what the priorities are that need to be addressed.”

The paper identifies five key opportunities for change that could result in better drinking and freshwater quality.

“If new standards for water quality are set we need to understand the costs, how we fund these and whether communities can afford them on their own,” Mr Cull says.

“We need to partner to meet these quality and funding challenges so we are all part of a single system, while also recognising our respective roles and responsibilities.”

The paper was launched at the LGNZ Water Summit, where national and international speakers are exploring issues around drinking water regulation, funding for three waters infrastructure, alternative options for the delivery of water services and challenges in freshwater management.

The paper is the second from LGNZ’s Water 2050 project which seeks to develop an integrated water policy framework.

It will be followed by a discussion paper on Cost and Funding, which considers funding options for water infrastructure and an issues paper on water infrastructure that will focus on the costs and investment challenges of rising standards, impacts of climate change and new regulation.

Source: Local Government New Zealand

ESR scientists look into mānuka’s potential for cleansing waterways

Scientists are testing whether mānuka trees and woodchips can help clean the country’s waterways,  Jerome Cvitanovich​ reports on Stuff.

Mr Cvitanovich​, a writer at ESR, says that while important and complex public debates are being had about the state of our fresh water, scientists have been working behind the scenes on a range of practical solutions to improve water quality.

A field trial under way in the North Island is using mānuka trees to intercept and clean farm runoff.

The report quotes Dr Maria Gutierrez-Gines, a scientist at ESR, who says the anti-microbial properties of mānuka honey are already well established.  But laboratory tests show that the root system of the trees also can reduce pathogens and nitrates.

“In the laboratory based tests E. coli died off much faster under mānuka than pasture, and significantly reduced the leaching of nitrate when they were compared with both pasture and pine trees. We think it can also influence run-off from farms.”

The ESR-led Centre for Integrated Biowaste Research is now running field trials looking at mānuka’s potential for reducing nutrients, sediments and pathogens from entering waterways in the Waikato farm catchment.

A trial at Lake Waikare is being run in partnership with local iwi, Canterbury University, EcoQuest, the Waikato River Authority and the Waikato Regional Council. The lake is the largest of system of shallow lakes in the lower Waikato catchment and has extremely poor water quality.

Planting started last year in a four-hectare block near the lake that had been donated by local landowners – the Nikau Farm Trust. Dr Gutiérrez-Gines says preliminary results following the community planting of over 40,000 trees already shows an encouraging increase in soil biodiversity.

The trial has funding for five years and researchers will be measuring the quantity and quality of the run-off as it passes through the biological barrier created by the trees.

Removing nitrate in groundwater is also a focus for ESR’s groundwater scientists who are looking at solutions to reduce nitrate levels accumulating in gravel aquifer systems.

One project is examining whether wood chip bioreactors are a viable method for reducing nitrate loads in farm drainage water and filtering nitrate from contaminated groundwater.

The woodchips remove nitrate in water by providing a carbon food source for bacteria, which convert nitrates to nitrogen gas.

Senior ESR groundwater scientist Dr Lee Burbery​ says gravel aquifers have no natural ability to reduce nitrate. He says that while bioreactors are already being used to treat land drainage in countries like the US, and are being used to treat industrial wastewater in New Zealand, it is not known how they might perform in the New Zealand agricultural landscape.

Dr Burbery says a woodchip bioreactor is being installed on an artificial farm drain at a site near Geraldine, South Canterbury, Scientists at ESR are also finalising the design of a woodchip “wall” that they will be trialling in the Silverstream catchment, north of Christchurch.

The wall involves the “strategic placement of a woodchip mixture below the water table to intercept the flow of shallow groundwater tainted with nitrate. The woodchip acts as a porous reactive medium, passively removing nitrate from groundwater filtering through it.”

There has already been some experimental work on this type of woodchip walls in New Zealand but this is the first time they will be trialled in a gravel aquifer.

Burbery says a lot of research has been done to understand the groundwater flow-paths at the experimental site, to help with the design of the wall.

Mr Cvitanovich​ references this published research on mānuka’s role in mitigating nitrates and pathogens





Another paper reviews denitrifying bioreactors


Source: Stuff


Victoria University research tackles nitrate pollution in waterways

Research carried out at Victoria University of Wellington has made big strides in tackling New Zealand’s serious nitrate pollution problem.

PhD student Putri Fraser, together with researchers from the University’s School of Chemical and Physical Sciences, have combined iron and natural silicates to create a safer, easier method of removing nitrate pollution from waterways.

Nitrate pollution destroys river habitats and aquatic life.

“Previous research shows that nano-sized iron can remove pollutants from soil and waterways, but it’s not a perfect solution,” Putri says.

“The iron is magnetic, so these nano-sized particles can clump up, reducing their reactivity and also making them difficult to work with. This clumping can also occur if they are ingested by fish, potentially harming wildlife.”

Putri needed to find a way of making the nano-sized iron less likely to clump but still maintain its reactivity towards pollutants.

She tested several different products, but the solution came in the form of a microsilicate product she first encountered while working as a Summer Research Scholar at Callaghan Innovation in 2012.

“This microsilicate product is cheap to produce and is a by-product of thermal power generation,” Putri says. “My supervisor (Dr Robin Fulton from Victoria University’s School of Chemical and Physical Sciences) and I thought it was very fitting to use another waste product to deal with nitrate waste.”

Putri says they were able to coat the microsilicate with the nano-sized iron, effectively increasing the size of the nano-iron while maintaining its reactivity.

“Coating the silicate with the iron makes it easier to distribute the iron in a solution, so the soil gets better coverage,” Putri says.

“Also, as the silicate-coated nanoparticles cannot clump, we don’t have to worry about any potential negative interactions with fish.

Dr Fulton says Putri’s research is significant.

“Not only has she made new materials for removing nitrate from waterways, she has also discovered that the ability of the nano-sized iron to remove nitrates is strongly influenced by the minerals around it.

“This discovery has implications for determining the best strategies for using nano-sized iron to address many environmental pollution issues.”

The next step is to see if this method can help with other pollutants.

“Along with a research team at the School of Chemical and Physical Sciences, I’m going to try different metals and coatings to see if there is a more effective combination, and also to see it’s possible to remove other pollutants from the soil using this method,” Putri says.

Putri will graduate with a PhD in Chemistry at Victoria University’s May graduation next week.

Source: Victoria University of Wellington

New technology aims to slash dairy effluent and farmers’ use of fresh water

Lincoln University has teamed up with the fertiliser co-operative, Ravensdown, to develop a breakthrough technology that could dramatically improve the dairy sector’s water efficiency and reduce the risks associated with dairy effluent.

The new system, known as ClearTech, was developed from research by Lincoln University Soil Science Professors Keith Cameron and Hong Di. It represents a $1.5 million investment by Ravensdown.

The technology aims to save billions of litres of freshwater a year by making existing effluent storage go further, with farmers able to separate effluent from dairy shed runoff and reuse the water. The leftover waste can then be turned into nutrient fertiliser for paddocks.

Professor Keith Cameron says the ClearTech pilot project was producing 10,000 litres of recyclable water per milking.

“That’s 20,000 litres a day of water saved, which means we don’t have to use freshwater, and it’s 20 thousand less litres of effluent that get produced,” he said.

The pilot project is installed at the Lincoln University Demonstration Farm (LUDF) and undergoing rigorous testing in a real-world environment to give farmers a preview of the technology.

It was unveiled at a LUDF Farm Focus Day on 3 May by Agriculture Minister Damian O’Connor and representatives from Lincoln University and Ravensdown. A group of 350 dairy farmers attended the event.

The system is installed between the dairy shed and effluent pond and works by binding effluent particles together to settle them out from the water.

The effluent circulating in the ClearTech system is automatically monitored and treated and the separation process kills up to 99% of micro-organisms, such as E. coli, while reducing odour.

Professor Hong Di said similar technology was being used for treating drinking water.

“We’ve taken the same principle and applied it to dairy farm effluent.”

The technology will be commercially available later this year, once testing has been completed.

Ravensdown Effluent Technology Manager Jaime Thompson said the project showed exciting potential to transform “green water” so it could be confidently reused as yard wash.

“About a quarter of a dairy shed’s fresh water use is on yard washing, so the potential benefits to New Zealand are enormous.

“ClearTech will look to save 42 billion litres of freshwater a year – the equivalent of 17,000 Olympic-sized swimming pools.”

She said 70 per cent of dairy farmers’ environmental spending was dedicated to effluent management, so ClearTech would help them to save money and meet their compliance obligations.

Professor Cameron also highlighted a positive initial response to the technology from dairy industry stakeholders.

“We’re really encouraged to see their willingness and desire to collaborate as we engage with them in the development of ClearTech,” he said.

Source: Lincoln University