Destroying vegetation along fences and roads could worsen our extinction crisis — yet the NSW government just allowed it


Shutterstock

Euan Ritchie, Deakin University; Ben Moore, Western Sydney University; Jen Martin, The University of Melbourne; Mark Hall, Western Sydney University; Megan C Evans, UNSW, and Ross Crates, Australian National UniversityWhat do koalas, barking owls, greater gliders, southern rainbow skinks, native bees, and regent honeyeaters all have in common? Like many native species, they can all be found in vegetation along fences and roadsides outside formal conservation areas.

They may be relatively small, but these patches and strips conserve critical remnant habitat and have disproportionate conservation value worldwide. They represent the last vestiges of once-expansive tracts of woodland and forests, long lost to the chainsaw or plough.

And yet, the NSW government last week made it legal for rural landholders to clear vegetation on their properties, up to 25 metres from their property boundaries, without approval. This radical measure is proposed to protect people and properties from fires, despite the lack of such an explicit recommendation from federal and state-based inquiries into the devastating 2019-20 bushfires.

This is poor environmental policy that lacks apparent consideration or justification of its potentially substantial ecological costs. It also gravely undermines the NSW government’s recent announcement of a plan for “zero extinction” within the state’s national parks, as the success of protected reserves for conservation is greatly enhanced by connection with surrounding “off-reserve” habitat.

Small breaks in habitat can have big impacts

A 25m firebreak might sound innocuous, but when multiplied by the length of property boundaries in NSW, the scale of potential clearing and impacts is alarming, and could run into the hundreds of thousands of kilometres.

Some plants, animals and fungi live in these strips of vegetation permanently. Others use them to travel between larger habitat patches. And for migratory species, the vegetation provides crucial refuelling stops on long distance journeys.

For example, the roadside area in Victoria’s Strathbogie Ranges shown below is home to nine species of tree-dwelling native mammals: two species of brushtail possums, three species of gliders (including threatened greater gliders), common ringtail possums, koalas, brush-tailed phascogales, and agile antenchinus (small marsupials).

Roadside and fenceline vegetation is often the only substantial remnant vegetation remaining in agricultural landscapes. This section, in northeast Victoria’s Strathbogie Ranges, running north to south from the intersection, is home to high arboreal mammal diversity, including the threatened greater glider.
Google Earth

Many of these species depend on tree hollows that can take a hundred years to form. If destroyed, they are effectively irreplaceable.

Creating breaks in largely continuous vegetation, or further fragmenting already disjointed vegetation, will not only directly destroy habitat, but can severely lower the quality of adjoining habitat.

This is because firebreaks of 25m (or 50m where neighbouring landholders both clear) could prevent the movement and dispersal of many plant and animal species, including critical pollinators such as native bees.

An entire suite of woodland birds, including the critically endangered regent honeyeater, are threatened because they depend on thin strips of vegetation communities that often occur inside fence-lines on private land.

Ecologically-sensitive fence replacement in regent honeyeater breeding habitat.
Ross Crates

For instance, scientific monitoring has shown five pairs of regent honeyeaters (50% of all birds located so far this season) are nesting or foraging within 25m of a single fence-line in the upper Hunter Valley. This highlights just how big an impact the loss of one small, private location could have on a species already on the brink of extinction.




Read more:
Only the lonely: an endangered bird is forgetting its song as the species dies out


But it’s not just regent honeyeaters. The management plan for the vulnerable glossy black cockatoo makes specific recommendation that vegetation corridors be maintained, as they’re essential for the cockatoos to travel between suitable large patches.

Native bee conservation also relies on the protection of remnant habitat adjoining fields. Continued removal of habitat on private land will hinder chances of conserving these species.

Glossy black cockatoos rely on remnant patches of vegetation.
Shutterstock

Disastrous clearing laws

The new clearing code does have some regulations in place, albeit meagre. For example, on the Rural Fire Service website, it says the code allows “clearing only in identified areas, such as areas which are zoned as Rural, and which are considered bush fire prone”. And according to the RFS boundary clearing tool landowners aren’t allowed to clear vegetation near watercourses (riparian vegetation).

Even before introducing this new code, NSW’s clearing laws were an environmental disaster. In 2019, The NSW Audit Office found:

clearing of native vegetation on rural land is not effectively regulated [and] action is rarely taken against landholders who unlawfully clear native vegetation.

The data back this up. In 2019, over 54,500 hectares were cleared in NSW. Of this, 74% was “unexplained”, which means the clearing was either lawful (but didn’t require state government approval), unlawful or not fully compliant with approvals.

Landholders need to show they’ve complied with clearing laws only after they’ve already cleared the land. But this is too late for wildlife, including plant species, many of which are threatened.




Read more:
The 50 beautiful Australian plants at greatest risk of extinction — and how to save them


Landholders follow self-assessable codes, but problems with these policies have been identified time and time again — they cumulatively allow a huge amount of clearing, and compliance and enforcement are ineffective.

Vegetation along roadsides and close to fences can be critical habitat for greater gliders.

We also know, thanks to various case studies, the policy of “offsetting” environmental damage by improving biodiversity elsewhere doesn’t work.

So, could the federal environment and biodiversity protection law step in if habitat clearing gets out of hand? Probably not. The problem is these 25m strips are unlikely to be referred in the first place, or be considered a “significant impact” to trigger the federal law.

The code should be amended

Nobody disputes the need to keep people and their assets safe against the risks of fire. The code should be amended to ensure clearing is only permitted where a genuinely clear and measurable fire risk reduction is demonstrated.

Many native bees, like this blue-banded bee (Amegilla sp.), will use the nesting and foraging resources available in remnant vegetation patches.
Michael Duncan

Granting permission to clear considerable amounts of native vegetation, hundreds if not thousands of metres away from homes and key infrastructure in large properties is hard to reconcile, and it seems that no attempt has been made to properly justify this legislation.

We should expect that a comprehensive assessment of the likely impacts of a significant change like this would inform public debate prior to decisions being made. But to our knowledge, no one has analysed, or at least revealed, how much land this rule change will affect, nor exactly what vegetation types and wildlife will likely be most affected.

A potentially devastating environmental precedent is being set, if other regions of Australia were to follow suit. The environment and Australians deserve better.




Read more:
‘Existential threat to our survival’: see the 19 Australian ecosystems already collapsing


Clarification: some text has been added to clarify the land cleared is on the landowner’s property, not outside their property boundaryThe Conversation

Euan Ritchie, Professor in Wildlife Ecology and Conservation, Centre for Integrative Ecology, School of Life & Environmental Sciences, Deakin University; Ben Moore, Senior Lecturer in Ecology, Hawkesbury Institute for the Environment, Western Sydney University; Jen Martin, Leader, Science Communication Teaching Program, The University of Melbourne; Mark Hall, Postdoctoral research fellow, Hawkesbury Institute for the Environment, Western Sydney University; Megan C Evans, Lecturer and ARC DECRA Fellow, UNSW, and Ross Crates, Postdoctoral fellow, Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Bushfire survivors just won a crucial case against the NSW environmental watchdog, putting other states on notice


Shutterstock

Laura Schuijers, The University of MelbourneThis week was another big one in the land of climate litigation.

On Thursday, a New South Wales court compelled the state Environment Protection Authority (EPA) to take stronger action to reduce greenhouse gas emissions. It’s the first time an Australian court has ordered a government organisation to take more meaningful action on climate change.

The case challenging the EPA’s current failures was brought by a group of bushfire-affected Australians. The group’s president said the ruling means those impacted by bushfires can rebuild their homes, lives, and communities, with the confidence the EPA will also work to do its part by addressing emissions.

The group’s courtroom success shows citizens can play an important role in bringing about change. And it continues a recent trend of successful climate cases that have held government and private sector actors to account for their responsibility to help prevent climate-related harms.

Who are the bushfire survivors?

Members of the group, the Bushfire Survivors for Climate Action, identify as survivors, firefighters and local councillors impacted by bushfires and the continued threat of bushfire posed by climate change.

Their stories paint a picture of devastating loss, and fear of what might be to come. One member, who lost her home, tells of harrowing hours looking for friends and family amid a dark, alien moonscape. Another, a volunteer firefighter, describes the smell of charred and burnt flesh and the silence of the incinerated forests that haunted him.

A person stands in a burnt-out home
Fiona Lee, a member of the Bushfire Survivors group, stands in the ruins of her home after a bushfire swept through.
Bushfire Survivors for Climate Action

The group argues that because the NSW EPA is required, by law, to protect the environment through quality objectives, guidelines and policies, these instruments also need to cover greenhouse gas emissions.

Their reasoning is hard to fault: climate change is one of the environment’s most significant threats. In today’s world, you can’t protect the environment without addressing climate change.

To establish this point, the bushfire survivors presented the latest report from the Intergovernmental Panel on Climate Change, which was released while the trial was being heard. The report describes how the temperature rise in Australia could exceed the global average, and predicts increasingly hotter and drier conditions.




Read more:
Climate change has already hit Australia. Unless we act now, a hotter, drier and more dangerous future awaits, IPCC warns


An unperformed duty

The EPA’s statutory duty to protect the environment was already known before the litigation began. That’s because the duty is contained within the EPA’s own legislation.

Bushfire survivors hold signs in front of Parliament House
The Bushfire Survivors brought their case to the NSW Land and Environment Court.
Bushfire Survivors for Climate Action

The EPA protects the environment from other types of pollutants by issuing environment protection licences, monitoring compliance, and imposing fines and clean-up orders. The bushfire survivors were seeking to force the EPA to address greenhouse gas emissions as well.

The EPA unsuccessfully tried to establish it is not required to address any specific environmental problem — i.e. climate change. And it argued that even if it is, it has already done enough.

But the court agreed with the bushfire survivors that the EPA’s instruments already in place aren’t sufficient, leaving the duty “unperformed”.

The court didn’t specify exactly how the EPA should remedy the fact it isn’t adequately addressing climate change, meaning the EPA can decide how it develops its own quality objectives, guidelines and policies, in a way that leads to fewer emissions. It is not the court’s job to make policy.

The EPA might, for example, target the highest-emitting industries and activities, via controls or caps on greenhouse gases.

Importantly, however, the court said the EPA doesn’t have to match its actions with a particular climate scenario, such as a global temperature rise of 1.5℃.

Other states on notice

Although this ruling is specific to NSW, other state environment protection authorities also have legal objectives to protect the environment.

This case may cause other Australian environmental authorities to consider whether their regulatory approaches match what the law requires them to do. This might include a responsibility to protect the environment from climate change.

Another thing we know from the NSW case is that simply having policies and strategies isn’t enough.

The court made it clear aspirational and descriptive plans won’t cut the mustard if there’s nothing to “set any objectives or standards, impose any requirements, or prescribe any action to be taken to ensure the protection of the environment”.

The EPA tried to point to NSW’s Climate Change Framework and Net Zero Plan as a way of showing climate change action. But neither of these was developed by the EPA.

The EPA also presented documents it did develop, including a document about landfill guidelines, a fact sheet on methane, and a regulatory strategy highlighting climate change as a challenge for the EPA.

The court found these weren’t enough to address the threat of climate change and discharge the EPA’s duty, calling the regulatory strategy’s description of climate change “general and trite”.

An Australian first, but not an anomaly

Globally, climate litigation is playing a role in filling gaps in domestic climate governance. Cases in Europe, North and South America, and elsewhere have led to courts pushing governments to do more.




Read more:
In a landmark judgment, the Federal Court found the environment minister has a duty of care to young people


One of the world’s first major successful climate change cases, Massachusetts v EPA, was similar to the bushfire survivors’ case. Back in 2007, the state of Massachusetts, along with other US states, sued the federal US EPA. They were seeking to force regulatory action on greenhouse gas emissions, and a recognition of carbon dioxide as a pollutant under the Clean Air Act.

While the NSW case comes 14 years after the US case, there has been plenty of courtroom action in Australia in the meantime, with cases against the financial sector, government actors, and corporations.

The top of the Santos building in front of a sunny blue sky
The Australasian Centre for Corporate Responsibility just filed a lawsuit against Santos.
Shutterstock

In fact, on the same morning as the bushfire survivors’ case, a lawsuit was filed against oil and gas giant Santos in the Federal Court.

The Australasian Centre for Corporate Responsibility will argue statements made in Santos’s annual report are misleading and deceptive. These statements include that natural gas is a “clean fuel” and that it has a “clear and credible” plan to achieve net-zero emissions by 2040.

Climate change is an inevitable problem, and one that will be costly. Lawsuits seeking to force action now aim to limit how great the costs will be down the track. By targeting those most responsible, they are a means of seeking justice.The Conversation

Laura Schuijers, Research Fellow in Environmental Law, The University of Melbourne

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The Murrumbidgee River’s wet season height has dropped by 30% since the 1990s — and the outlook is bleak


Murrumbidgee River, near Yass.
Nick Pitsas, CSIRO/Wikimedia Commons, CC BY-SA

Milton Speer, University of Technology Sydney and Lance M Leslie, University of Technology SydneyThe Murray-Darling Basin is Australia’s biggest agricultural region, producing almost 40% of the national food supply during the growing season from April to September. It’s filled with criss-crossing rivers, wetlands and lakes farmers rely on for crops, and it’s home to a range of freshwater wildlife, many of which are under threat.

But our new research found climate change since the 1990s has drastically reduced the amount of water available in the southern part of the basin.

The height of the Murrumbidgee River — the third longest in Australia and highly valued for irrigation and hydro-electricity — has dropped by about 30% during the growing season. This is a loss of approximately 300 million litres per day that would normally flow past Wagga Wagga, New South Wales — the same as six days of water use in the City of Melbourne.

The findings follow a major report the Intergovernmental Panel on Climate Change released on Monday, which found much of Australia will become more arid as the world warms. This will bring reduced river flows, mass tree deaths, more droughts and drier soils.

The viability of the basin is at stake. Continued drying and warming in Australia will cause water availability to decline even further, deepening the hurt for communities, businesses, animals and the environment. Any decisions about the competing interests of agriculture and the environment must keep these global warming impacts front of mind.

What we found

The southern Murray-Darling Basin occupies the southern half of NSW and northern Victoria. It receives most of its water from rain in the cooler months that fills dams, with any overflow spilling into the floodplains.

But our research shows rainfall in April to May has significantly decreased which, in turn, has caused the net inflows to the Murrumbidgee River catchment in the southern basin to decrease. This includes in the main dams of Burrinjuck and Blowering in the upper part of the catchment, and downstream river heights.

Murrumbidgee River catchment makes up 8% of the Murray-Darling Basin.
Conquimbo/Wikimedia Commons, CC BY-SA

The Murrumbidgee River catchment is approximately 84,000 square kilometres, or about 8% of the basin. It encompasses a complex series of wetlands and floodplains, and supplies water for homes in many communities, including Wagga Wagga, Griffith and Leeton.

Using statistical analysis and machine learning, we found the Murrumbidgee River dropped from 3.5 metres in 1990 to 2.5 metres in 2019 during the cooler months. When you multiply this by the the length and breadth of the river, which stretches more than 1,400km, this is an enormous volume of water lost.

Given this drop is associated with the wettest months from April to September, the outlook for the warmer months between October and March is dismal. The number of days when the river ceases to flow will certainly increase.

Long, difficult droughts

Dam building and excessive irrigation are often behind decreased river flows across the Murray-Darling Basin. But in this case, we can point to decreased rainfall from climate change as the reason the Murrumbidgee River catchment is losing water.




Read more:
We looked at 35 years of rainfall and learnt how droughts start in the Murray-Darling Basin


The Burrinjuck Dam was completed in 1928 and the Blowering Dam was completed in the 1960s. Until the early 1990s, the Murrumbidgee River used to regularly spill over the banks at Wagga Wagga and also further downstream at Hay, during the cool seasons.

Likewise, we didn’t identify irrigation as a major contributor, because more than 80% of irrigation occurs downstream of Wagga Wagga.

The Murrumbidgee River is over 1,400 kilometres long, and flows past Wagga Wagga.
Shutterstock

Global warming has accelerated in the latter half of last century, and particularly since the 1990s in Australia.

To see its effect in Australia, we need only look to the extended drought conditions since the mid-1990s in the basin, comprising the Millennium Drought (1997-2009) and the 2017-2019 drought. They were extreme, even compared to the historical Federation Drought between 1895 and 1903.

In 2006, the Australian newspaper reported that inflows to the nearby River Murray system between June and November were 610 gigalitres, “just 56 percent of the previously recorded low in 1902” when the Federation Drought was at its worst.

Climate change exacerbates dry years

But climate change doesn’t tell the whole story, there are also other factors at play driving the low rainfall trend in the basin. Namely, natural climate phenomena form over the ocean and bring wetter or drier weather to various parts of Australia.

One of these climate phenomena is the Indian Ocean Dipole (IOD), which brings wetter weather than normal from June to October when in its “negative” phase (in fact, the Bureau of Meteorology recently declared another negative IOD for Australia this year, the first in five years).




Read more:
A wet winter, a soggy spring: what is the negative Indian Ocean Dipole, and why is it so important?


But in the last two decades there have been only two strongly negative-phase Indian Ocean Dipole (IOD) events affecting Australia. The current IOD phase is only moderately negative.

Climate drivers like this are entirely natural and have been occurring for thousands of years, but human-caused climate change exacerbates their influence. Generally, it makes dry seasons drier, and wet seasons wetter.

After years of little rain or snowmelt, evaporation accentuates the lack off run-off.
Shutterstock

In April this year, devastating floods engulfed western Sydney. This resulted in the dams reaching nearly 100% capacity last month. However, the river height at Wagga Wagga is currently around 5.3m and this is still 2m below the minor flood level of 7.3m — too low to overflow into the surrounding floodplain.

And after years of little rain or snowmelt, evaporation accentuates the lack off run-off into dams and streams, because water needs to soak into dry catchments before significant run-off can occur.

Profoundly disturbing implications

The implications of our research are profoundly disturbing, because it means the economic, social and ecological sustainability of the Murrumbidgee River catchment is at stake.

Under climate change, we can expect further drying of wetlands and major losses of wildlife habitat. For example, the mid-Murrumbidgee and the Lowbidgee wetlands are listed as nationally significant, providing critical habitat for threatened frogs, such as the vulnerable southern bell frog.

The southern bell frog is threatened by habitat loss and degradation, barriers to movement, predation, disease and exposure to biocides.
Shutterstock

For farmers and communities, we can expect huge reductions in the amount of water allocated for irrigation. The ability for communities to survive these severe decreases in agricultural productivity will be tested.

The efficiency of farm practices is improving. But because of the continuing threat of drought conditions in a warming climate, there’s an urgent need to plan for further decreases in rainfall, and further unreliability of water supply.

Australia needs a new review of water availability and sustainability in the Murrumbidgee and other river systems in the southern Murray-Darling Basin.




Read more:
Climate change has already hit Australia. Unless we act now, a hotter, drier and more dangerous future awaits, IPCC warns


The Conversation


Milton Speer, Visiting Fellow, School of Mathematical and Physical Sciences, University of Technology Sydney and Lance M Leslie, Professor, School of Mathematical And Physical Sciences, University of Technology Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

We asked landholders how they feel about biodiversity offsets — and the NSW government has a lot to learn


Shutterstock

Roel Plant, University of Technology Sydney and Laure-Elise Ruoso, University of Technology SydneyWhen land is cleared to make room for urban growth, infrastructure, mining, and so on, developers are often required to “offset” their environmental damage by improving biodiversity elsewhere. This could mean, for example, planting trees along a river, or building shelters for animals that lost their habitats.

In New South Wales, one mechanism to fulfil this requirement is the Biodiversity Offsets Scheme, and a NSW parliamentary inquiry into this scheme is currently underway. The inquiry will look into the scheme’s administration, transparency and oversight, and will investigate the ability for private landowners to engage in it.

This is where our research comes in. We interviewed landholders in Greater Metropolitan Sydney during 2019 and 2020 to find out if they can — and want to — participate in biodiversity offsets.

Our findings suggest the NSW government would be wise to open up its offset scheme to make it more equitable, diverse and socially acceptable.

Recent controversies

Australia is considered an international forerunner when it comes to biodiversity offsetting, with all Australian states and territories having some form in place (complemented by federal provisions).

But over the years, biodiversity offset schemes have been marred with controversy, particularly recently.

In April, The Guardian Australia revealed a single company had made more than A$40 million by buying land and then selling offsets on that land to the state and federal governments. The new inquiry is a direct response to this news report.

How landholders come into it

Landholders are essential to making biodiversity offsets successful. They play a pivotal role in how offsetting functions on the ground, and in safeguarding its outcomes.

For example, landholder work could involve removing stock, weed control, pest fauna management, fencing off the site or building nest boxes for birds whose trees were cut down.

To get involved in biodiversity offsetting in NSW, landholders must first enter an agreement with the government to enhance and maintain the biodiversity values of their land, in perpetuity.

They often generate a one-off profit when they enter the agreement, and receive yearly payments from the government to manage their land. These payments are funded by, for instance, developers and mining companies, who have been required under law to offset their developments.




Read more:
Artificial refuges are a popular stopgap for habitat destruction, but the science isn’t up to scratch


But while it’s been shown biodiversity offsets readily meet developers’ needs, the diverse perspectives of landholders remain poorly understood.

This knowledge gap is what inspired us to undertake research with landholders in Greater Sydney. This included conducting interviews with landholders and land managers, both participants and non-participants in the scheme.

Can landholders participate?

Four factors determined whether landholders participated in the scheme: experience, financial and staff resources, access to information and technical support, and property size.

Several participants had a good understanding of the scheme because of prior experience or involvement. Some had access to financial and staff resources (such as lawyers and property managers), while others were given information and technical support.

Having support like this gave them confidence to enter into an agreement and manage the land appropriately. One landholder told us:

I think I knew enough people who’d done it to know that they’d got through all of that [management of the land] without too much concern.

In contrast, landholders unable to participate generally didn’t have experience, resources, support or large properties. They often relied on online information and had a poor understanding of the scheme. They had many concerns, especially financial. One barrier they identified, for example, is the cost of the initial ecological assessment of the land.

A non-participant said:

We don’t want to outline money for something that we don’t really understand or know anything about and might not happen.

Do landholders want to participate?

A variety of ethical, financial, technical and governance-related factors influenced a landholders’ willingness to participate in offsets. Some don’t consider nature as something that can be substituted, and fundamentally disagreed with the very principles of offsets:

We shouldn’t be clearing [t]here and then growing stuff here. We just shouldn’t be clearing there.

Others consider the rules of the scheme not stringent enough to achieve positive ecological outcomes. Some have reservations about their technical ability to do the conservation work, and question the likelihood of “nature complying” with stated ecological outcomes.

Some landholders seek compensation only for their conservation actions — in other words, making a profit isn’t their goal. For others, the prospect of a profit is a determining factor, with some hesitant to participate because it would take away from potentially more lucrative property development options:

I suspect there’ll be rezoning of land and all sorts of things, so if we do [offsetting] we’re going to lose that potential.

And some landholders perceive participation, in perpetuity, interferes with their right to sell their land. They see the scheme as potentially diminishing the land value, or putting unnecessary burden on the next landowner.

Building artificial refuges like nest boxes is a popular offsetting project.
Shutterstock

What needs to change?

These findings tell us two things about the current scheme:

  1. financial and information barriers create unequal opportunities across landholders
  2. the scheme doesn’t cater to diverse conservation perspectives.

The NSW government should loosen up the narrow neo-liberal market principles underpinning the scheme and open it up to a wider range of landholders. As an immediate first step, the government could introduce a more equitable model for sharing the costs of the initial ecological assessment.

It could also open the scheme to a wider range of conservation perspectives.

Offsetting is meant to be used as a last resort, according to globally accepted standards for development projects.




Read more:
Can we really restore or protect natural habitats to ‘offset’ those we destroy?


If developers and the government clearly demonstrate habitat destruction is completely necessary and offsetting really is a last resort, then we expect broader acceptance among landholders. Further research is required to learn how the government could achieve this.

Such reforms would give the scheme a stronger social license to operate and ensure it meets its policy objectives better.

Importantly, opening up the scheme would make it more transparent, so that future excessive profit seeking, with questionable conservation outcomes, can be prevented.The Conversation

Roel Plant, Adjunct Professor, University of Technology Sydney and Laure-Elise Ruoso, Senior Research Consultant, University of Technology Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

A tale of two valleys: Latrobe and Hunter regions both have coal stations, but one has far worse mercury pollution


Shutterstock

Larissa Schneider, Australian National University; Anna Lintern, Monash University; Cameron Holley, UNSW; Darren Sinclair, University of Canberra; Neil Rose, UCL; Ruoyu Sun, and Simon Haberle, Australian National UniversityWe know coal-fired power stations can generate high levels of carbon dioxide, but did you know they can be a major source of mercury emissions as well?

Our new research compared the level of mercury pollution in the Hunter Valley in New South Wales and the Latrobe Valley in Victoria.

And we found power stations in the Latrobe Valley emit around 10 times more mercury than power stations in the Hunter Valley. Indeed, the mercury level in the Latrobe Valley environment is 14 times higher than what’s typically natural for the region.

So why is there such a stark difference between states? Well, it has a lot to do with regulations.

Following a NSW requirement for power stations to install pollution control technology, mercury levels in the environment dropped. In Victoria, on the other hand, coal-fired power stations continue to operate without some of the air pollution controls NSW and other developed countries have mandated.

To minimise the safety risks that come with excessive mercury pollution, coal-fired power stations in all Australian jurisdictions should adopt the best available technologies to reduce mercury emissions.

A dangerous neurotoxin

Mercury is a neurotoxin, which means it can damage the nervous system, brain and other organs when a person or animal is exposed to unsafe levels.

Coal naturally contains mercury. So when power stations burn coal, mercury is released to the atmosphere and is then deposited back onto the Earth’s surface. When a high level of mercury ends up in bodies of water, such as lakes and rivers, it can be transferred to fish and other aquatic organisms, exposing people and larger animals to mercury that feed on these fish.




Read more:
The death of coal-fired power is inevitable — yet the government still has no plan to help its workforce


Mercury does not readily degrade or leave aquatic environments such as lakes and rivers. It’s a persistent toxic element — once present in water, it’s there to stay.

The amount of mercury emitted depends on the type of coal burnt (black or brown) and the type of pollution control devices the power stations use.

The Latrobe Valley stations in Victoria burn brown coal, which has more mercury than the black coal typically found in NSW. Despite this, Victorian regulations have historically not placed specific limits on mercury emissions.

In contrast, NSW power plants are required to use “bag filters”, a technology that’s used to trap mercury (and other) particles before they enter the atmosphere.

While bag filters alone fall short of the world’s best practices, they can still be effective. In fact, after bag filters were retrofitted to Hunter Valley’s Liddell power station in the early 1990s, mercury deposition in the surrounding environment halved.

Mercury deposited in sediments of Lake Glenbawn (left) in the Hunter Valley and Traralgon Railway Reservoir (right) in the Latrobe Valley.

The best available technology to control mercury emissions from coal-fired power plants is a combination of “wet flue-gas desulfurization” (which removes mercury in its gaseous form) and bag filters (which removes mercury bound to particles).

This is what’s been adopted across North America and parts of Europe. It not only filters out mercury, but also removes sulphur dioxide, nitrogen oxides and other toxic air compounds.

Using lake sediments to see into the past

Lake sediments can capture mercury deposited from the atmosphere and from surrounding areas. Sediments that contain this mercury accumulate at the bottom of lakes over time — the deeper the sediment, the further back in time we can analyse.

We took sediment samples from lakes in the Latrobe and Hunter valleys, and dated them back to 1940 to get a historical record of mercury deposition.

This information can help us understand how much naturally occurring mercury there was before coal-fired power stations were built, and therefore show us the impact of burning coal.

A power station by a lake
Lake Narracan: one of the lakes we sampled sediments from, near a coal-fired power station in Latrobe Valley.
Larissa Schneider, Author provided

From these records, we found the adoption of bag filters in the Hunter Valley corresponded with mercury depositions declining in NSW from the 1990s.

In contrast, in Victoria, where there’s been no such requirement, mercury emissions and depositions have continued to increase since Hazelwood power station was completed in 1971.

What do we do about it?

In March, the Victorian government announced changes to the regulatory licence conditions for brown coal-fired power stations. Although mercury emissions allowances have been included for the first time, they’re arguably still too high, and there’s no requirement to install specific pollution control technologies.

There’s a risk this approach won’t reduce mercury emissions from existing levels. Victoria should instead consider more ambitious regulations that encourage the adoption of best practice technology to help protect local communities and the environment.

Coal-fired power station at the end of a road, at night
Loy Yang power station, Victoria’s largest, burns brown coal which contains more mercury.
Shutterstock

Another vital step toward protecting human health and the environment from mercury is for the federal government to ratify the Minamata Convention on Mercury, an international treaty to protect human health and the environment from mercury.

Despite signing the convention in 2013, the Australian government is yet to ratify it, which is required to make it legally binding in Australia.

Ratifying the convention will oblige state and federal governments to develop and implement a strategy to reduce mercury emissions, including from coal-fired power stations across Australia. And this strategy should include rolling out effective technologies — our research shows it can make a big difference.


The authors acknowledge Lauri Myllyvirta from the Centre for Research on Energy and Clean Air for her contributions to this article.




Read more:
Hazelwood power station: from modernist icon to greenhouse pariah


The Conversation


Larissa Schneider, DECRA fellow, Australian National University; Anna Lintern, Lecturer, Monash University; Cameron Holley, Professor, UNSW; Darren Sinclair, Professor, University of Canberra; Neil Rose, Professor of Environmental Pollution and Palaeolimnology, UCL; Ruoyu Sun, Associate Professor, and Simon Haberle, Professor, Australian National University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Beautiful, rare ‘purple cauliflower’ coral off NSW coast may be extinct within 10 years


Author supplied

Meryl Larkin, Southern Cross University; David Harasti, Southern Cross University; Steve Smith, Southern Cross University, and Tom R DavisWhen we think of Australia’s threatened corals, the Great Barrier Reef probably springs to mind. But elsewhere, coral species are also struggling – including a rare type known as “cauliflower soft coral” which is, sadly, on the brink of extinction.

This species, Dendronephthya australis, looks like a purple cauliflower due to its pink-lilac stems and branches, crowned with white polyps.

The coral primarily occurs at only a few sites in Port Stephens, New South Wales, and is a magnet for divers and underwater photographers. But sand movements, boating and fishing have reduced the species’ population dramatically.

Recent flooding in NSW compounded the problem – in fact, it may have reduced the remaining coral population by 90%. Our recent research found cauliflower soft coral may become extinct in the next decade unless we urgently protect and restore it.

An ovulid on a cauliflower coral colony. Such coral may be extinct within a decade.
Author supplied

Lilac underwater gardens

Cauliflower soft corals are predominantly found in estuarine environments on sandy seabeds with high current flow. They rely on tidal currents to transport plankton on which they feed.

The species is most commonly found in the Port Stephens estuary, about 200 kilometres north of Sydney. It’s also found in the Brisbane Water estuary in NSW, and has been found sporadically in other locations south to Jervis Bay.

The coral colonies form aggregations or “gardens”. At Port Stephens, these gardens are the preferred habitat for the endangered White’s seahorse and protected species of pipefish. They also support juvenile Australasian snapper, an important species for commercial and recreational fishers.

In recent months, the cauliflower soft coral has been listed as endangered in NSW and nationally.




Read more:
Marine life is fleeing the equator to cooler waters. History tells us this could trigger a mass extinction event


An alarming decline

Scientists first mapped the distribution of the cauliflower soft coral in 2011. They found none of the biggest colonies in the Port Stephens estuary were protected by “no take” zones – areas where fishing and other extractive activities are banned.

In research in 2016, we found a sharp decline in the extent and distribution of cauliflower soft coral.

Our recent study examined the problem in more detail. It involved mapping the southern shoreline of Port Stephens, using an underwater camera towed by a vessel.

We found the cauliflower soft coral in the Port Stephens estuary has declined by almost 70% over just eight years. It now occurs over 9,300 square metres – down from 28,600 square metres in 2011.

Our subsequent modelling sought to identify what was driving the corals’ decline. We found a correlation between coral loss and sand movements over the last decade.

Human changes to shorelines, such as marina developments, have changed the dynamic of currents across the estuary. For example, previous research found a large influx of sand from the western end of Shoal Bay smothered cauliflower soft coral colonies at two nearby locations. As of 2018, those colonies had disappeared completely.

While diving as part of the project, we identified other causes of damage to the coral. Dropped boat anchors and the installation of moorings had damaged some colonies. Others were injured after becoming entangled in fishing line.

It is possible that disease, and pollution or other water quality issues, may also be contributing to the species’ decline.

Fishing line damaging a colony of cauliflower soft coral in Port Stephens.
Author supplied

Then the floods hit

Some 18 months after our most recent mapping, cauliflower soft corals suffered yet another blow. Major flooding in NSW in March this year caused a massive amount of fresh water to discharge from the Karuah River into the Port Stephens estuary, where sea water is dominant. Fresh water can kill cauliflower soft corals.

Following the floods, we conducted exploratory dives at locations where the cauliflower soft corals had been thriving at Port Stephens. We found much of the coral had disintegrated and disappeared. In fact, we estimated as much as 90% of the remaining cauliflower soft coral population was gone.

We plan to remap the estuary in the coming weeks, and feel confident our initial estimates will be close to the mark. If so, this means less than 5% of the species area mapped in 2011 now remains.

The floods also devastated kelp forests and other canopy-forming habitats in the estuary. Further work by scientists at the NSW Department of Primary Industries is underway to quantify these losses and monitor the recovery.




Read more:
Sydney’s disastrous flood wasn’t unprecedented: we’re about to enter a 50-year period of frequent, major floods


Monitoring of existing cauliflower coral aggregations is ongoing.
Author supplied

Urgent work required

The cauliflower soft coral urgently needs protecting. This will require ongoing, coordinated research and management.

Clearly, action must be taken to reduce threats such as anchoring, fishing, and development that may magnify sand movement.

Best-practice rehabilitation is also needed. This may involve rearing the coral off-site and transplanting it into suitable habitat. Such trials at Port Stephens have shown promising signs.

Human activities are causing species loss at an alarming rate. We must do everything in our power to prevent the extinction of the cauliflower soft coral, and other threatened species, to preserve the balance of nature and its ecosystems.




Read more:
Australia’s threatened species plan sends in the ambulances but ignores glaring dangers


The Conversation


Meryl Larkin, PhD Candidate, Southern Cross University; David Harasti, Adjunct assistant professor, Southern Cross University; Steve Smith, Professor of Marine Science, National Marine Science Centre, Southern Cross University, and Tom R Davis, Research Scientist – Marine Climate Change

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Victoria’s new feral horse plan could actually protect the high country. NSW’s method remains cruel and ineffective


Shutterstock

Don Driscoll, Deakin UniversityFeral horses are a catastrophic problem for the environment, particularly in the high country that crosses the New South Wales and Victoria border. To deal with this growing issue, the Victorian government has released a draft feral horse action plan, which is open for comment until April 23.

It comes after Victoria’s old action plan from 2018 proved ineffective, with feral horse numbers increasing in the most recent counts in 2019. This is similar to New South Wales’ current performance, where feral horses are legally protected and numbers are essentially unmanaged.

This new Victorian plan has flaws, but it’s still likely to perform better than the old plan (and the very low benchmark set by NSW), as it generally aims to deploy evidence-based management of national parks.

As Victoria gets on top of its feral horse problem, NSW will be left further behind with a degrading environment and rising costs of horse management.

The feral horse threat

Feral horses degrade ecosystems and threaten native Australian species with their heavy trampling and excessive grazing. They damage waterways and streamside vegetation which, in turn, threatens species that live in and alongside the streams, such as the alpine spiny crayfish, the alpine water skink and the Tooarrana broad-toothed rat. All of these are threatened species.

Damage from feral horses could worsen as ecosystems recover from the extensive 2019-20 eastern Australian bushfires. Horse grazing could delay animals’ habitat recovery and horse trampling could exacerbate stream degradation after fires.

In fact, there are 24 species that need protection from feral horses after the fires, as identified by the Australian government’s wildlife and threatened species bushfire recovery expert panel in September.

All of this ecosystem destruction translates into substantial economic costs. Frontier Economics released a report in January this year showing the potential benefits of horse control in Kosciuszko National Park was A$19-50 million per year. The benefits accrue through improved recreational opportunities, improved water quality and reduced car crashes involving feral horses.

In contrast, horse control could cost as little as A$1 million per year and up to $71 million, depending on the methods used. Frontier Economics concluded the costs that are incurred by keeping feral horses far outweigh the cost of eradication.

Alpine water skink
Alpine water skinks are among the vulnerable native species threatened by feral horses.
DEPI/Flickr, CC BY-SA

Victoria’s new feral horse plan

The draft Victorian feral horse action plan aims to:

  1. remove isolated populations on the Bogong High Plains within three years and prevent new populations from establishing
  2. contain and reduce feral horses in the eastern Alps by removing 500 horses in the first year
  3. use the most humane, safe and effective horse control methods.

The first aim makes complete sense. Removing small populations will always be more humane, cheaper and better for the environment than leaving them uncontrolled.

The second aim is perplexing. Based on 2019 surveys, the draft action plan says there are approximately 5,000 horses in the eastern Alps and the population is growing at 15% per year. If the government continues to remove 500 horses per year after the first year, it could see the population rise to more than 9,000 over ten years, despite culling 5,000 horses in that time.




Read more:
Double trouble as feral horse numbers gallop past 25,000 in the Australian Alps


In contrast, removing 2,000 horses per year could see the population controlled within three years. Reducing horse numbers rapidly results in the fewest horses having to be culled in the long term.

The third aim of the Victorian draft action plan gives appropriate and strong emphasis to animal welfare. Controlling horse numbers can be morally challenging, and requires a clear understanding of the trade-offs.

Without horse control, native animals are killed when their habitat is destroyed, unique Australian ecosystems are degraded, horses themselves starve or die of thirst in droughts, and the economic costs of inaction escalate. To avoid these costs, horse numbers must be reduced by culling.

This is the grim reality, but with careful attention to animal welfare, the draft strategy will ensure horse control is managed humanely, with control methods based on evidence rather than hyperbole.

Money wasting in NSW

Victoria’s plan is in stark contrast to the NSW government’s approach. In 2018, the NSW government passed the so-called “brumby bill”, which protects feral horses in Kosciuszko National Park.




Read more:
Passing the brumby bill is a backward step for environmental protection in Australia


The current method of control in NSW is to capture the horses and transport them to an abattoir if they cannot be re-homed. But evidence shows culling has fewer animal welfare concerns than this method.

And in the latest round of money-wasting horse management, the NSW government trapped 574 horses over the past year, but released 192 females and foals back into the park. If the program is aimed at reducing horse numbers, releasing the most fertile animals back into the population is counter-productive.

Regenerating plants and burnt trees in fire-damaged alpine region
Feral horses are exacerbating the damage from recent bushfires in the High Country.
Shutterstock

What’s more, removing 300-400 horses per year has little impact on overall numbers. There are around 14,000 horses in Kosciuszko National Park, with a growth rate of 23% per year. This means more than 3,000 horses must be removed just to prevent the population from getting bigger.

The high country without feral horses

If the Victorian draft plan can be improved to invest in rapid horse reduction and ecosystem restoration, we can expect to see quagmires created by trampling horses return to functioning ecosystems and the recovery of threatened species.

Stream banks can be stabilised and then dense grass tussocks and sedges will return, creating homes for threatened skinks, crayfish and the Tooarrana broad-toothed rat.

While Kosciuszko’s alpine ecosystems continue to decline under the NSW government’s political impasse, the Victorian Alps will become the favoured destination for tourists who want to see Australia’s nature thriving when they visit national parks.




Read more:
To fix Australia’s environment laws, wildlife experts call for these 4 changes — all are crucial


The Conversation


Don Driscoll, Professor in Terrestrial Ecology, Deakin University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Sydney’s disastrous flood wasn’t unprecedented: we’re about to enter a 50-year period of frequent, major floods


Tom Hubble, University of SydneyLast month’s flood in the Hawkesbury-Nepean River region of western Sydney peaked at a staggering 12.9 metres, with water engulfing road signs and reaching the tops of many houses.

There hasn’t been a major flood on the Hawkesbury-Nepean for more than 30 years, with the last comparable one occurring in 1990. Long-term Sydneysiders, however, will remember that 12 major floods occurred during the 40 years before 1990. Five of these were larger than last month’s flood.

So what’s going on? The long-term rainfall pattern in the region and corresponding river flow is cyclic in nature. This means 40 to 50 years of dry weather with infrequent small floods are followed by 40 to 50 years of wet weather with frequent major floods.

As river and floodplain residents take stock of the recent damage to their homes and plan necessary repairs, it’s vital they recognise more floods are on the way. Large, frequent floods can be expected to occur again within 10 or 20 years if — as expected — the historical pattern of rainfall and flooding repeats itself.

Living in a bathtub

Many of the 18,000 people who were evacuated live in and around a region known as the “Sackville Bathtub”. As the name suggests, this flat, low-lying section of the floodplain region was spectacularly affected.

The flooded Hawkesbury-Nepean River last month. Brown floodwater is evident between Penrith (right) and the Pacific Ocean (top left). The Sackville Bathtub is located left of centre.
Digital Earth Australia Map, Geoscience Australia, Tom Hubble

The Sackville Bathtub is located between Richmond and Sackville. It’s part of the Cumberland Plain area of Western Sydney and formed very slowly over 100 million years due to plate tectonic processes. The bathtub’s mudstone rock layers are folded into a broad, shallow, basin-shaped depression, which is surrounded by steep terrain.

Downstream of Sackville, the Hawkesbury-Nepean River flows through sandstone gorges and narrows in width. This creates a pinch-point that partially blocks the river channel.

Just as a bath plug sitting half-way over a plughole slows an emptying bath, the Sackville pinch-point causes the bathtub to fill during floods.

How the bathtub effect in the Hawkesbury-Nepean Valley causes floodwaters to back up and lead to deep and dangerous flooding.

Will raising the dam wall work?

The NSW state government is planning to raise the wall of the Warragamba Dam to help mitigate catastrophic floods in the region. But this may not be an effective solution.

Typically, somewhere between 40% and 60% of the floodwater that fills up the Sackville Bathtub comes from unimpeded, non-Warragamba sources. So, when the Hawkesbury-Nepean River floods, the bathtub is already quite full and causing significant problems before Warragamba begins to spill. The Warragamba water then raises the flood level, but often by only a couple of metres.

Raising Warragamba Dam’s wall as a mitigation measure will only control about half the floodwater, and won’t prevent major floods delivered by the Nepean and Grose rivers, which also feed into the region. This represents a small potential benefit for a very large cost.

The timing of observed flood peaks during the August 1986 Hawkesbury-Nepean flood, in relation to the time when Warragamba Dam began to spill. The arrival of Warragamba water in the Sackville Bathtub increased the flood depth only by about a metre above the floodwaters delivered earlier during the flood from the Grose and Nepean rivers.
Tom Hubble – Redrawn from data presented in Appendix One of the Hawkesbury-Nepean Flood Study; Infrastructure NSW 2019.

A long flooding period is on our doorstep

The idea of drought-dominated and flood-dominated periods for the Hawkesbury-Nepean River system was proposed in the mid-1970s by the University of Sydney’s Robin Warner. Since the late 1990’s, it hasn’t been the focus of much research.




Read more:
What is a 1 in 100 year weather event? And why do they keep happening so often?


He showed a century-long cycle of alternating periods of dry weather and small floods followed by wet weather and big floods is normal for Sydney. This means the March flood may not have come as a surprise to older residents of the Sackville Bathtub, who have a lived experience of the whole 40-50 year flooding cycle.

As a rough average, one major flood occurred every four years during the last wet-weather period between 1950 and 1990. The largest of this period occurred in November 1961. It filled the Sackville Bathtub to a depth of 15 metres and — like the June 1964 (14.6 metres) and March 1978 (14.5 metres) events — caused more widespread flooding than this year’s flood.

A photo of a flood that occured in Maitland in September 1950.
Sam Hood/NSW State Library/Flickr, CC BY

We’re currently 30 years into a dry period, which may be about to end. Conditions might stay dry for another 10 or 20 years.

These cycles are likely caused by natural, long-term “climate drivers” — long-term climatic fluctuations such as El Niño and La Niña, the Pacific Decadal Oscillation and the Indian Ocean Dipole, which are driven by oceanic current circulations. These global phenomena bring both benevolent weather and destructive weather to Australia.

Eastern Australia experiences decades-long periods of wetter weather when these climate drivers sync up with each other. When they’re out of sync, we get dry weather periods.




Read more:
A rare natural phenomenon brings severe drought to Australia. Climate change is making it more common


These long-term cycles are natural and have been operating for thousands of years, but climate change is amplifying and accelerating them. Dry periods are getting drier, wet periods are getting wetter.

The good news and bad news

The bad news is that 12-plus metre floods at Hawkesbury River (Windsor Bridge) are not all that unusual. There have been 24, 12-plus metre floods at Windsor Bridge since 1799.

The good news is meteorological forecasters are excellent at predicting when the storms that generate moderate, large and catastrophic floods are coming. We can expect several days’ to a week’s notice of the next big flood.

We can also prepare our individual and communal responses for more large and frequent floods on the Hawkesbury-Nepean. Residents of the area need to think about how they might live near the river as individuals. Decide what is precious and what you will fit into a car and trailer. Practice evacuating.

As a community, we must ensure the transport infrastructure and evacuation protocols minimise disruption to river and floodplain residents while maximising their safety. It’s particularly important we set up inclusive infrastructure to ensure disadvantaged people, who are disproportionately affected by disasters, also have a fighting chance to evacuate and survive.




Read more:
Not ‘if’, but ‘when’: city planners need to design for flooding. These examples show the way


Upgrading the escape routes that enable people to evacuate efficiently is absolutely vital. As is rethinking whether we should continue urban expansion in the Sackville Bathtub.

So remember, the next major flood is going to occur sooner than we would like. If you live in this region, you must start preparing. Or as a wise elder once said, “Live on a floodplain, own a boat!”


This story is part of a series The Conversation is running on the nexus between disaster, disadvantage and resilience. Read the rest of the stories here.The Conversation

Tom Hubble, Associate Professor, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Water markets are not perfect, but vital to the future of the Murray-Darling Basin



kaman985shu/Shutterstock

Neal Hughes, Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES)

Water markets have come in for some bad press lately, fuelled in part by the severe drought of 2019 and resulting high water prices.

They have also been the subject of an Australian Competition and Consumer Commission inquiry, whose interim report released last year documented a range of problems with the way water markets work in the Murray-Darling Basin. The final report was handed to the treasurer last week.

While water markets are far from perfect, new research from the Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES) has found they are vital in helping the region cope with drought and climate change, producing benefits in the order of A$117 million per year.

To make the most of water markets, we will need to keep improving the rules and systems which support them. But with few “off-the-shelf” solutions, further reform will require both perseverance and innovation.

Water markets generate big benefits

Australia’s biggest and most active water markets are in the southern Murray-Darling Basin, which covers the Murray River and its tributaries in Victoria, NSW and South Australia.

Murray Darling Basin.
MDBA

Each year water right holders are assigned “allocations”: shares of water in the rivers’ major dams. These allocations can be traded across the river system, helping to get water where it is most needed.

Water markets also allow for “carryover”: where rights holders store rather than use their allocations, holding them in dams for use in future droughts.

Our research estimates that water trading and carryover generate benefits to water users in the southern Murray-Darling, of A$117 million on average per year (around 12% of the value of water rights) with even larger gains in dry years. Carryover plays a key role, accounting for around half of these benefits.

Together water trading and carryover act to smooth variability in water prices, while also slightly lowering average prices across the basin.

There’s room for improvement

One of many issues raised in the Australian Competition and Consumer Commission interim report was the design of the trading rules, including limits on how much water can move between regions.

These rules are intended to reflect the physical limits of the river system, however getting them right is extremely difficult.

The rules we have are relatively blunt, such that there is potential at different times for either too much water to be traded or too little.

National Electricity Market.
AGL

One possible refinement is a shift from a rules-based system to one with more central coordination.

For example, in electricity, these problems are addressed via so-called “smart markets”: centralised computer systems which balance demand and supply across the grid in real-time.

Such an approach is unlikely to be feasible for water in the foreseeable future.

But a similar outcome could be achieved by establishing a central agency to determine inter-regional trade volumes, taking into account user demands, river constraints, seasonal conditions and environmental objectives.

While novel in Australia, the approach has parallels in the government-operated “drought water banks” that have emerged in some parts of the United States.

Some of the good ideas are our own

Another possible refinement involves water sharing rules, which specify how water allocations are determined and how they are carried over between years.

At present these rules are often complex and lacking in transparency. This can lead to a perceived disconnect between water allocations and physical water supply, creating uncertainty for users and undermining confidence in the market.

Although markets in the northern Murray-Darling Basin are generally less advanced than the south, some sophisticated water sharing systems have evolved in the north to deal with the region’s unique hydrology (highly variable river flows and small dams).

Beardmore Dam at St George in Southern Queensland, where water markets operate under a capacity sharing system.
ABARES

There is potential for the southern basin to make use of these northern innovations (known as “capacity sharing” or “continuous accounting”) to improve transparency and carryover decisions.

Don’t throw the market out with the river water

Governance failures in the water market have led to understandable frustration.

But it is important to remember how vital trading and carryover are in smoothing variations in water prices and making sure water gets where it is needed, especially during droughts.

The ACCC’s final report (due soon) will provide an opportunity to take stock and develop a roadmap for the future.


Water markets will be discussed at Today’s ABARES Outlook 2021 conference in an online panel session at 3-4pm AEDT.The Conversation

Neal Hughes, Senior Economist, Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES)

This article is republished from The Conversation under a Creative Commons license. Read the original article.