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


Chiara Holgate, Australian National University; Albert Van Dijk, Australian National University, and Jason Evans, UNSW

The extreme, recent drought has devastated many communities around the Murray-Darling Basin, but the processes driving drought are still not well understood.

Our new study helps to change this. We threw a weather model into reverse and ran it back for 35 years to study the natural processes leading to low rainfall during drought.




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And we found the leading cause for drought in the Murray-Darling Basin was that moisture from oceans didn’t reach the basin as often as normal, and produced less rain when it did. In fact, when moisture from the ocean did reach the basin during drought, the parched land surface actually made it harder for the moisture to fall as rain, worsening the already dry conditions.

These findings can help resolve why climate models struggle to simulate drought well, and ultimately help improve our ability to predict drought. This is crucial for our communities, farmers and bushfire emergency services.

There’s still a lot to learn about rain

The most recent drought was relentless. It saw the lowest rainfall on record in the Murray-Darling Basin, reduced agricultural output, led to increased food prices, and created tinder dry conditions before the Black Summer fires.

Drought in the Murray-Darling Basin is associated with global climate phenomena that drive changes in ocean and atmospheric circulation. These climate drivers include the El Niño and La Niña cycle, the Indian Ocean Dipole and the Southern Annular Mode.

Each influences the probability of rainfall over Australia. But drivers like El Niño can only explain around 20% of Australian rainfall — they only tell part of the story.




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To fully understand the physical processes causing droughts to begin, persist and end, we need to answer the question: where does Australia’s rainfall come from? It may seem basic, but the answer isn’t so simple.

Where does Australia’s rainfall come from?

Broadly, scientists know rainfall derives from evaporation from two main sources: the ocean and the land. But we don’t know exactly where the moisture supplying Australia’s rainfall originally evaporates from, how the moisture supply changes between the seasons nor how it might have changed in the past.

To find out, we used a sophisticated model of Australia’s climate that gave data on atmospheric pressure, temperature, humidity, winds, rainfall and evaporation.




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We put this data into a “back-trajectory model”. This traced the path of water from where it fell as rain, backwards in time through the atmosphere, to uncover where the water originally evaporated from. We did this for every day it rained over Australia between 1979 and 2013.

Not surprisingly, we found more than three-quarters of rain falling in Australia comes from evaporation from the surrounding oceans. So what does this mean for the Murray-Darling Basin?

Up to 18% of rain in the basin starts from the land

During the Millennium Drought and other big drought years (such as in 1982), the Murray-Darling Basin heavily relied on moisture transported from the Tasman and Coral seas for rain. Moisture evaporated off the east coast needs easterly winds to transport it over the Great Dividing Range and into the Murray-Darling Basin, where it can form rain.

This means low rainfall during these droughts was a result of anomalies in atmospheric circulation, which prevented the easterly flow of ocean moisture. The droughts broke when moisture could once again be transported into the basin.

A lack of vegetation on the land can exacerbate drought.
Shutterstock

The Murray-Darling Basin was also one of the regions in Australia where most “rainfall recycling” happens. This is when, following rainfall, high levels of evaporation from soils and plants return to the atmosphere, sometimes leading to more rain – particularly in spring and summer.

This means if we change the way we use the land or the vegetation, there is a risk we could impact rainfall. For example, when a forest of tall trees is replaced with short grass or crops, humidity can go down and wind patterns change in the atmosphere above. Both of these affect the likelihood of rain.




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In the northern part of the basin, less evaporation from the dry land surface exacerbated the low rainfall.

On the other hand, when the drought broke, more moisture evaporated from the damp land surface, adding to the already high levels of moisture coming from the ocean. This meant the region got a surplus of moisture, promoting even more rain.

This relationship was weaker in the southern part of the basin. But interestingly, rainfall there relied on moisture originating from evaporation in the northern basin, particularly during drought breaks. This is a result we need to explore further.

Summer rain not so good for farmers

Rainfall and moisture sources for Australia and the Murray-Darling Basin are changing. In the past 35 years, the southeast of the country has been receiving less moisture in winter, and more in summer.

This is likely due to increased easterly wind flows of moisture from the Tasman Sea in summer, and reduced westerly flows of moisture from the Southern Ocean in winter.

This has important implications, particularly for agriculture and water resource management.

For example, more rainfall in summer can be a problem for horticultural farms, as it can make crops more susceptible to fungal diseases, decreases the quality of wine grape crops and affects harvest scheduling.

Less winter rain also means less runoff into creeks and rivers — a vital process for mitigating drought risk. And this creates uncertainty for dam operators and water resource managers.




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Understanding where our rainfall comes from matters, because it can improve weather forecasts, seasonal streamflow forecasts and long-term rainfall impacts of climate change. For a drought-prone country like Australia — set to worsen under a changing climate — this is more crucial than ever.The Conversation

Chiara Holgate, Hydrologist & PhD Candidate, Australian National University; Albert Van Dijk, Professor, Water and Landscape Dynamics, Fenner School of Environment & Society, Australian National University, and Jason Evans, Professor, UNSW

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

Morrison government plan to scrap water buybacks will hurt taxpayers and the environment



Shutterstock

Quentin Grafton, Crawford School of Public Policy, Australian National University

The Morrison government today declared it will axe buybacks of water entitlements from irrigators, placating farmers who say the system has damaged their livelihood and communities.

Instead, Water Minister Keith Pitt says the government will scale up efforts to save water by upgrading infrastructure for farming irrigators in the Murray Darling Basin.

The move will anger environmentalists, who say water buybacks are vital to restoring flows to Australia’s most important river system. It also contradicts findings from the government’s own experts this week who said farm upgrades increase water prices more than buyback water recovery.

The government has chosen a route not backed by evidence, and which will deliver a bad deal to taxpayers and the environment.

A farmer stands in the dry river bed of the Darling River
The government will no longer buy water from farmers for the environment.
Dean Lewins/AAP

A brief history of water buybacks

Farmers along the Murray Darling are entitled to a certain amount of river water which they can use or sell. In 2008, the federal Labor government began buying some of these entitlements in an open-tender process known as “buybacks”. The purchased water was returned to the parched river system to boost the environment.

In 2012, the Murray Darling Basin Plan was struck. It stipulated that 2,750 billion litres of water would be bought back from irrigators and delivered to the environment every year. The buyback system was not universally supported – critics claim buybacks increase water prices, and hurt farmers by reducing the water available for irrigation.

The Coalition government came to office in 2013 and adopted a “strategic” approach to water buybacks. These purchases were made behind closed doors with chosen irrigators.




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In a review of these buybacks released last month, the Australian National Audit Office found many of these taxpayer-funded deals were not good value for money.

The federal government ordered the review after controversy involving the 2017 purchase of water from two Queensland properties owned by Eastern Australia Agriculture.

The government paid A$80 million for the entitlements – an amount critics said was well over market value. The deal was also contentious because government frontbencher Angus Taylor was, before the purchase, a non-financial director of the company. The company also had links to the Cayman Islands tax haven.

Keith Pitt speaks in Parliament as Prime Minister Scott Morrison watches on
Water Minister Keith Pitt, pictured during Question Time, is the minister responsible for the new approach.
Mick Tsikas/AAP

Infrastructure subsidies: a flawed approach

The Coalition government is taking a different approach to recover water for the environment: subsidising water infrastructure on farms and elsewhere. This infrastructure includes lining ponds and possibly levees to trap and store water.

The subsidies have cost many billions of dollars yet recover water at a very much higher cost than reverse tenders. This approach also reduces the water that returns to streams and groundwater.




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The justification for water infrastructure subsidies is that they are supposedly less damaging to irrigation communities. But the Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES) concluded in a report published this week that on-farm water infrastructure subsidies, while beneficial for their participants, “push water prices higher, placing pressure on the wider irrigation sector”. This is the very sector the subsidies purport to help.

So why would the government expand the use of water infrastructure when it costs more and isn’t good value for money? The answer may lie in this finding from the ABARES report:

Irrigators who hold large volumes of entitlement relative to their water use (and are frequently net sellers of water allocations) may benefit from higher water prices, as this increases the value of their entitlements.

Farmers with limited entitlement holdings however may be adversely affected, as higher water prices increase their costs and lowers their profitability.

In other words, the “big end of town” benefits – at taxpayers’ expense – while the small-scale irrigators lose out.

Missing water

Adding insult to injury, the Wentworth Group of Concerned Scientists released a detailed report this week showing the basin plan is failing to deliver the water expected, even after accounting for dry weather. Some two trillion litres of water is not in the rivers and streams of the basin and appears to have been consumed – a volume that could be more than four times the water in Sydney Harbour.

The Wentworth Group says stream flows may be less than expected because environmental water recovery has been undermined by “water-saving” infrastructure, which reduces the amount of water that would otherwise return to rivers and groundwater.

This infrastructure, on which taxpayers have spent over A$4 billion, has not had the desired effect. Research has found those who receive infrastructure subsidies increased water extractions by more than those who did not receive subsidies. That’s because farmers who were using water more efficiently often planted thirstier crops.

Dusk at Menindee Lakes in the Murray Darling Basin
The government took a strategic approach to water buybacks in the Murray Darling Basin.
Shutterstock

We deserve better

It’s clear taxpayer dollars are much better spent buying back water entitlements, through open tenders, rather than subsidising water infrastructure. We can, and must, do much better with water policy.

Today, the federal government has doubled down on wasteful spending at taxpayer expense – in a time of a COVID-induced recession.

So what is on offer from the Morrison government? Continuing to ignore its own experts’ advice and delivering yet more ineffective subsidies for water infrastructure. Our rivers, our communities, and all Australians deserve much better.




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The Conversation


Quentin Grafton, Director of the Centre for Water Economics, Environment and Policy, Crawford School of Public Policy, Australian National University

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

Recovering water for the environment in the Murray-Darling: farm upgrades increase water prices more than buybacks



Murray Darling Junction, Wentworth NSW.
Hypervision Creative/Shutterstock

Neal Hughes, Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES); David Galeano, Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES), and Steve Hatfield-Dodds, Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES)

It’s been 13 years since the Australian Government set out to develop the Murray-Darling Basin Plan with the goal of finding a more sustainable balance between irrigation and the environment.

Like much of the history of water sharing in the Murray-Darling over the last 150 years, the process has been far from smooth. However, significant progress has been achieved, with about 20% of water rights recovered from agricultural users and redirected towards environmental flows.

One of the most difficult debates has been over how the water should be recovered.

Initially most occurred via “buybacks” of water rights from farmers. While relatively fast and inexpensive, opposition to buybacks emerged due to concerns about their effects on water prices and irrigation farmers and regional communities.

This led to a new emphasis on infrastructure programs including farm upgrades in which farmers received funding to improve their irrigation systems in return for surrendering water rights.

While these farm upgrades are more expensive, it was thought that they would have fewer negative effects on farmers and communities.

However, new research from the Australian Bureau of Agricultural and Resource Economics and Sciences finds that – while beneficial for their participants – these programs push water prices higher, placing pressure on the wider irrigation sector.

Two types of water recovery programs

The Murray-Darling Basin operates under a “cap and trade” system. Each year there is a limit on how much water can be extracted from the basin’s rivers, based on the available supply.

Water users (mostly farmers) hold rights to a share of this limit, and they can trade these rights on a market.

To date 1,230 gigalitres of these water rights have been bought from farmers via buyback programs at a cost of about A$2.6 billion.




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The other type of program is farm upgrades which offer farmers funding to improve their irrigation infrastructure in return for a portion of their water rights.

To date 255 gigalitres of water has been recovered through farm upgrades at a cost of about $1 billion.


Annual volume of water rights recovered for the environment since 2007-08

For infrastructure projects the financial year refers to the contract date. The actual transfer of entitlements may occur in a later financial year. The volume of water recovered is expressed in terms of the long-term average annual yield. The estimates do not include water recovered through state projects (160 gigalitres) or water gifted to the Commonwealth (15 gigalitres). Off-farm infrastructure includes water recovered through projects that are a combination of on-farm, off-farm and land purchases.
Sources: Department of Agriculture Water and Environment, Commonwealth Environmental Water Holder

Water recovery has increased prices

As would be expected, the dominant short-term driver of prices is water availability, with large price increases during droughts. The dominant longer-term drivers include lower average rainfall related to climate change and the emergence of new irrigation crops including almonds.

While water recovery has played less of a role, buybacks and farm upgrades have still reduced the supply of water to farmers and increased prices to some extent.




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Our modelling suggests water prices in the southern basin are around $72 per megalitre higher on average as a result of water recovery measures, with the effects varying year-to-year depending on conditions.


Modelled water allocation prices with and without water recovery

Price refers to volume weighted average annual water allocation prices across the southern Murray Darling Basin. Water recovery reflects the cumulative volume of buybacks and farm upgrades at each year. Water recovery began in 2007-08.
ABARES modelling

Farm upgrades increase prices more than buybacks

Farm upgrades are often viewed as an opportunity to save water and produce “more crop per drop”.

But they can also encourage farmers to increase their water use as they seek to make the most of their new infrastructure: sometimes referred to as a “rebound effect”.

While there have been concerns about rebound effects for some time, there has been limited evidence until recently.

Less-wasteful irrigation can save water, as long as there’s no ‘rebound’

As would be expected, our study finds that upgraded farms have benefited in terms of profits and productivity. However, we also find large rebound effects, with upgraded farms increasing their water use by between 10% and 50%.

To get the extra water they need to buy it from other farmers, putting pressure on prices. We find the resulting price impact to be much more than the impact of buying back water. Per unit of water recovered, it is about double that of buybacks.

These higher water prices increase the risk that irrigation assets – including some newly upgraded systems – could become stranded as price sensitive irrigation activities become less profitable.

No easy answers

Recovering water through off-farm infrastructure is one alternative, however the most effective projects have already been developed, leaving cost-effective water saving schemes harder to find.

This brings us back to buybacks. Because buybacks are cheaper than farm infrastructure programs, there is more scope to combine them with regional development investments to help offset negative impacts on communities.

The challenge is that in a connected water market the flow-on effects on water prices and farmers can be complex and difficult to predict, making it hard to know where to direct development investments.




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A potential middle ground is rationalisation, where parts of the water supply network are decommissioned, and affected farmers are compensated both for their water rights and for being disconnected from water supply. This approach has less effect on water prices and allows regional development initiatives to be targeted to the affected areas.

However, rationalisation can be hard to implement given it requires negotiating with all affected farmers and all levels of government.

Given the complexity of the Murray-Darling Basin, water policy is far from simple. While it is clear more water will be needed to put the basin on a sustainable footing, there are no easy options.

Further progress will require careful policy design to help ease adjustment pressure on farmers and regional communities.The Conversation

Neal Hughes, Senior Economist, Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES); David Galeano, Assistant Secretary, Natural Resources, Australian Bureau of Agricultural and Resource Economics and Sciences (ABARES), and Steve Hatfield-Dodds, Executive Director, 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.

Before and after: see how bushfire and rain turned the Macquarie perch’s home to sludge



Mannus Creek in NSW during the 2020 bushfire period.
Luke Pearce, Author provided

Lee Baumgartner, Charles Sturt University; Katie Doyle, Charles Sturt University; Luiz G M Silva, Charles Sturt University; Luke Pearce, and Nathan Ning, Charles Sturt University

This article is a preview of Flora, Fauna, Fire, a multimedia project launching on Monday July 13. The project tracks the recovery of Australia’s native plants and animals after last summer’s bushfire tragedy. Sign up to The Conversation’s newsletter for updates.


The unprecedented intensity and scale of Australia’s recent bushfires left a trail of destruction across Australia. Millions of hectares burned and more than a billion animals were affected or died. When the rains finally arrived, the situation for many fish species went from dangerous to catastrophic.

A slurry of ash and mud washed into waterways, turning freshwater systems brown and sludgy. Oxygen levels plummeted and water quality deteriorated rapidly.

Hundreds of thousands of fish suffocated. It was akin to filling your fish tank with mud and expecting your goldfish to survive.

Take, for example, the plight of the endangered Macquarie perch (Macquaria australasica), an Australian native freshwater fish of the Murray-Darling river system.

A Macquarie perch.
Luke Pearce, Author provided



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A special fish

Macquarie perch were once one of the most abundant fish in the Murray-Darling Basin. Revered by the community and once responsible for supporting extensive Indigenous, recreational, commercial and subsistence fisheries, they are an iconic species found nowhere else in the world. However, they have very specific needs.

Macquarie perch like rocky river sections with clear, fast-flowing water, shaded by trees and bushes on the banks.

Massive change wrought on our rivers over the past century means Macquarie perch are now only found at a handful of locations in the Murray-Darling Basin.

One habitat – Mannus Creek near the NSW Snowy Mountains – is particularly special because it was relatively pristine before the fires. In fact, this creek contained the last population of the threatened Macquarie perch in the NSW Murray catchment. A study in 2017 found a Macquarie perch population that was restricted to a 9km section of the creek but was doing quite well.

That was until bushfire rapidly swept through the catchment in January this year.

Some of us visited the creek three weeks after the fires. The intensity, ferocity and speed of the fires meant nothing was spared. The former forest floor was literally a trail of death and destruction – dead and charred kangaroos, wallabies, deer, possums and birds were everywhere.

All that remained of Mannus Creek was green pools in a blackened landscape, still smouldering days after the fire front passed. We immediately feared for the Macquarie perch we’d sampled, which were quite healthy less than a year before.

To our surprise, some Macquarie perch had survived. But with most of the catchment fully burnt, and no vegetation to stop runoff, we knew it was a ticking time bomb.

A desperate rescue attempt

With little time, we had to remove as many fish as possible from Mannus Creek before the rains arrived. The plan was to create an “insurance population” in case rain caused the water conditions to deteriorate.

We rescued ten fish. Days later, rain washed ash and silt into the channel. Within hours, the once-pristine creek became flowing mud with the consistency of cake mix.

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A government rescue team arrived a few days later to rescue more fish, and despaired at the “wall of ash and mud”.

An ark across Australia

Those ten individual Macquarie perch now live in an “ark” of at-risk species, spanning government and private hatchery facilities.

The ark is housing not only the Macquarie perch but other threatened species too. The rescued individuals, and perhaps their entire species, would have almost certainly perished during runoff events without these interventions.

Now a waiting game begins.

What next for the Macquarie perch?

Nobody knows for sure how many fish survived in Mannus Creek, nor how long it will take for the creek to recover. It could be years.

Ash and mud flow into Lake Macquarie after the fires.
Luke Pearce, Author provided

The challenge now is to support the rescued fish until it’s safe to either return them to the creek, or breed offspring and introduce them to their natural habitat.

Fish must be kept healthy and disease-free in captivity, and enough genetic diversity must be maintained for the population to remain viable.

If these rescued fish are held in captivity for too long, they might die. But equally worrying is that affected waterways may not recover in time to allow reintroduction.




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While maintaining the rescued populations, we must redouble our efforts to improve their natural habitats.

Burnt areas can allow pest plant and animal species to take hold and change habitats, so these threats need to be controlled. Finding similar, unburnt refuge areas is also crucial to prepare for future events and protect ecosystem resilience.

Working through these considerations – and quickly – is essential to giving these species the best hope of survival.

Funding, equipment and human resources are desperately needed to help our rivers recover. But we know that without an effective on-ground intervention, recovery could take decades.

For the iconic Macquarie perch, that would be too late.




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The Conversation


Lee Baumgartner, Professor of Fisheries and River Management, Institute for Land, Water, and Society, Charles Sturt University; Katie Doyle, Freshwater Ecologist, Charles Sturt University; Luiz G M Silva, Freshwater Fish Scientist, Charles Sturt University; Luke Pearce, Fisheries Manager, and Nathan Ning, Freshwater Ecologist, Charles Sturt University

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

Restoring a gem in the Murray-Darling Basin: the success story of the Winton Wetlands



Lance Lloyd, Author provided

Max Finlayson, Charles Sturt University and Lance Lloyd, Federation University Australia

Water use in the Murray-Darling Basin has long been a source of conflict. Damage to rivers and wetlands, including fish kills and algal blooms, has featured prominently in the news.

But the Winton Wetlands, in the south-east basin, represents a bright spot. Its restoration provides a sense of hope that reaches beyond the complexities of history.

The wetlands site is about 2.5 hours drive north-east of Melbourne. It’s now a thriving place for plants and wildlife that attracts plenty of visitors – but it wasn’t always like this.

A laughing kookaburra keeps watch on the wetlands.
Diana Padron/Flickr, CC BY-ND

From dispossession to decommissioning

The Yorta Yorta people were the original Aboriginal inhabitants of the area. They lost access to the land and water when European settlers took it for farming in the 1860s.

The farmers and the wetlands were displaced in 1970 when a 7.5 kilometre rock wall was built to form Lake Mokoan. The dam project allowed for local irrigation and created a drought reserve for the River Murray. This was broadly welcomed for the economic and recreational values it promised.

It worked for a while, but the resulting flooding killed around 150,000 iconic river red gums, including many Aboriginal scar trees.

River red gum trees died following inundation after the dam was built.
Max Finlayson, Author provided

The dam was dried out for downstream supplies in the 1982 drought. Then the 1990s brought massive blue-green algal blooms.

The frequent blooms made it hard to use the water. The Victorian government needed to find water savings for water projects elsewhere and in 2004 decided to remove the dam.

It was a controversial move, opposed by many in the community, including those who lived around the lake, or used the water for recreation or irrigation. But in 2009 a gap was cut through the wall and the water drained.

Local opposition to the decommissioning of the dam.
Max Finlayson, Author provided

Restoration of the wetlands

After the dam was decommissioned, it was clear the site had undergone significant ecological and social change. So the government was keen to establish a world-class wetland with close links to nearby communities.

In 2009 an independent, community-based committee of management was formed to renew the site.

The scale of the renewal is significant, covering 8,750 hectares. It’s the first site outside the US to be classed as a Wetland of Distinction by the Society of Wetland Scientists, a leading global voice for wetland science and management.

Importantly, local Indigenous people are actively involved in the project, which recognises Indigenous cultural heritage sites throughout the wetlands.

This runs alongside efforts to document and share the history of the European settlers. The committee recognises that people in the wetlands have more than once moved from occupation to dispossession.

Winton Wetlands aerial views – December 2011.

The ecological renewal is built around specific management actions to establish self-sustaining populations of native fish, waterbirds and other fauna, and aquatic plants. It’s also improving the water quality and reducing the populations of feral animals and weeds.

Native plants returned to the site include the river red gum and cane grass.

Native fish are breeding, as is the majestic white-bellied sea eagle. A rakali (Australia’s answer to otters) and sugar gliders have been sighted.




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An advisory panel is guiding the science behind the project. It’s supported by research partnerships with universities and an annual science forum, designed as an information exchange between the committee and the wider community.

A cafe and visitors hub are now regularly used for events. People visit the wetlands for walks, bike rides, canoeing, stargazing and birdwatching.

There are 60km of roads, nine bush walks, 30km of cycling trails and artworks celebrating the landscape and its history.

The decommissioning of the dam was not well received by some in the community at first. The restoration project is working hard to repair the connection of people to the site through ecological renewal, art and recreational events.

New trees planted as part of the Winton Wetland revegetation during dry periods.
Lance Lloyd, Author provided

If you restore it, they will come

The success of the Winton Wetlands project in involving the community is reflected in increasing visitor numbers to the site. These have grown from 36,264 in 2016-17 to 65,287 in 2018-19.

In addition, the numbers of schoolchildren who visit the site for guided nature excursions has increased from 274 in 2016-17 to 2,013 in 2018-19.

Volunteers are also playing a role with some 4,114 hours of effort in 2018-19 operating the information desk, taking guided walks, organising planting days and other restoration activities. Volunteers support the science work in various ways including long-term monitoring of frog calls.




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The management committee is determined to rebuild the ecological integrity of the wetlands. But there is a lot still to do, and there are differences of opinion over the priorities and the speed at which things are being done.

The initial funding of A$17 million from the Victorian government will soon be exhausted. Other financial avenues are being pursued. This is necessary to secure a future for this bright spot – a gem of inestimable value – in the Murray-Darling Basin.The Conversation

The Winton Wetlands represent a bright spot for social-ecological restoration and renewal in the Murray-Darling Basin.
Lance Lloyd, Author provided

Max Finlayson, Adjunct Professor, Charles Sturt University and Lance Lloyd, Honorary Research Fellow, Federation University Australia

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

No water, no leadership: new Murray Darling Basin report reveals states’ climate gamble


Daniel Connell, Crawford School of Public Policy, Australian National University

A report released today investigating how states share water in the Murray Darling Basin describes a fascinating contrast between state cultures – in particular, risk-averse South Australia and buccaneering New South Wales.

Perhaps surprising is the report’s sparse discussion of the Murray Darling Basin Plan, which has been the focus of irrigators’ anger and denunciation by National Party leaders: Deputy Prime Minister Michael McCormack and NSW Deputy Premier John Barilaro.

In general terms, the Murray Darling Basin Plan was originally intended to make water management in the Murray Darling Basin more environmentally sustainable. Its critics see it as a restraint on development, and complain it has taken water away from irrigators during a time of extreme drought.




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In response to McCormack and Barliaro’s criticisms of the plan in late 2019, federal water minister (and senior National Party figure) David Littleproud commissioned Mick Keelty as Interim Inspector General of MDB Water Resources.

For the new report, Keelty investigated the changing distribution of “inflows” – water flowing into the River Murray in the southern states.

Climate change has brought the inflow to just a trickle. This dramatic reduction over the past 20 years is what Keelty has described as “the most telling finding”.




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He also investigated the reserve policies under which the three states choose – or don’t choose – to hold back water in Hume and Dartmouth Dams to manage future droughts.

Keelty says there’s little transparency or clarity about how much water states are allocated under the Murray Darling Basin Agreement (the arrangement for sharing water between the states which underpins the Basin Plan). This failure in communication and leadership across such a vital system must change.

Sharing water across three states

One major finding of Keelty’s inquiry is that the federal government has little power to change the MDB Agreement between the three states, which was first approved in 1914-15. Any amendment requires the approval of all three governments.

To increase the volume of water provided to NSW irrigators, South Australia and Victoria would need to agree to reduce the volumes supplied to their own entitlement holders. That will not happen.

Why has the agreement lasted so long?

Over the past century it has proved robust under a wide range of conditions. Its central principle is to share water with a proportion-of-available-flow formula, giving each state a percentage of whatever is available, no matter whether it’s a lot, or not much.

After receiving its share of the River Murray flows, each state is then free to manage its allocation as it wishes.




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Historically, South Australia and Victoria have chosen to reserve or hold back a larger proportion of their shares each year in Hume and Dartmouth dams to use in future droughts, compared with New South Wales.

In part this difference derives from the long-term water needs of orchards and vines in South Australia and Victoria, in contrast to annual crops such as rice and cotton in New South Wales.

As a result, South Australia and Victoria have a higher proportion of high security entitlements. That means they receive 100% most years. Only in extreme drought years is their allocation reduced.

NSW, on the other hand, has a higher proportion of low security general entitlements. In dry and normal years they receive a proportion of their entitlements. Only in wet years do they get the full 100%. (These differences in reliability are reflected in the cost of entitlements on the water market.)

Reliability of water supply

What’s more, each state makes its own decision about how its state allocation is shared between its entitlement holders (95% of water goes to irrigators the rest supplies towns and industry).

South Australia chooses to distribute a much smaller proportion to its entitlement holders than New South Wales. It also restricted the number of licences in the 1970s. That combination ensures a very high level of reliability in supply. Victoria took a similar approach.




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But New South Wales did not restrict licences until the 1990s. It also recognised unused entitlements, so further reducing the frequency of years in which any individual would receive their full allocation of water.

When climate change is taken into account these differences between the three states result in their irrigators having significantly different risk profiles.

The climate change threat to the basin is very real

Despite climate denial in the National Party, the threat is very real in the MDB. The report describes a massive reduction in inflows over the past 20 years, approximately half compared with the previous century. One drought could be an aberration, but two begins to look like a pattern.

The report also suggests that in many cases irrigator expectations of what should be normal were formed during the wet period Australia experienced between the second world war and the 1990s.

Added to this have been business decisions by many irrigators to sell their entitlements and rely on the water market, a business model based on what now seems like unrealistic inflow expectations.




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In effect, successive New South Wales governments – a significant part of the state’s irrigation sector in the southern part of the state and the National Party – gambled against the climate and are now paying a high price.

In desperation, they’re focusing on alternative sources. This includes the water in Hume and Dartmouth held under the reserves policy of the two other states; environmental entitlements managed by the Commonwealth Environmental Water Holder; the very large volume of water lost to evaporation in the lower lakes in South Australia; and the possibility of savings resulting from changes to management of the system by the Murray-Darling Basin Authority.

Failure in leadership and communication

For reasons already outlined, the state reserves policy is not likely to change and use of the Commonwealth Environmental Water Holder environmental water entitlements would not be permitted under current legislation.

Management of the lower lakes is being reviewed through another investigation so is not discussed in the report. The report also states that management of the MDB Authority is subject to regular detailed assessment by state governments, and they have assessed its performance as satisfactory.




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However the report was critical of the performance of all MDB governments with regard to leadership and communications suggesting that failures in those areas were largely responsible for the public concern which triggered its investigation.The Conversation

Daniel Connell, Research Fellow, Crawford School of Public Policy, Australian National University

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

Don’t blame the Murray-Darling Basin Plan. It’s climate and economic change driving farmers out


Sarah Ann Wheeler, University of Adelaide

For the thousand or so farmers in Canberra in the past week venting their anger at the federal government, it’s the Murray-Darling Basin Plan to blame for destroying their livelihoods and forcing them off the land.

We can’t comment directly on their claims about the basin plan. But our research, looking at the years 1991 to 2011, suggests little association between the amount of water extracted from the Murray-Darling river system for irrigation and total farmer numbers.

That’s not to say there aren’t fewer farms in the basin now than a decade ago – there are – but our analysis points to the more important drivers being the longer-term influences of changing climate, economics and demographics.

Indeed our study predicts another 0.5℃ increase in temperature by 2041 will halve the current number of farmers in the basin.

Hostility to water recovery

The waters of the northern basin run to the Darling River and the waters of the southern basin run to the Murray River.
MDBA

Over many decades state governments in Queensland, New South Wales, Victoria and South Australia licensed to farmers more entitlements to water than the river system could sustain. The basis of the Murray-Darling Basin Plan, enacted in 2012, was to rectify this through buying back about a quarter of all water licences to ensure an environmental flow.

A water entitlement, despite its name, does not guarantee a licence holder a certain amount of water. That depends on the water available, and that is determined by the states, which make allocations to each type of licence based on its type of security and current conditions.

With drought, farmers have seen their allocations severely cut back, sometimes to nothing. And partly because they see there’s still water in the River Murray, some are very angry.




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Hostility to water recovery in fact predates the plan’s enactment, to when the federal government began buying back water entitlements in 2008. The Commonwealth now holds about 20% of water entitlements across the basin. More than two-thirds of these licences were recovered between 2008 and 2012.

Lack of correlation

Our research thus covers the period of most significant water buybacks. It also covers the period of the Millennium Drought, from 2001 to 2009, when the amount of water extracted from the river system dropped by about 70%.

Yet we see little evidence reduced water extractions led to more farmers exiting the industry.

As a very broad overview of the situation, the following graph illustrates the lack of correlation between measured water extraction in the Murray-Darling Basin and decreasing farmer numbers.



Water extractions have varied significantly between years, with a big decline over the decade of the 2000s even while farmers’ need for irrigated water increased due to lack of rain. La Niña brought record rains in 2010-11. The current drought across the basin took grip from about 2017.

Yet farmer numbers have declined at a relative steady rate. Within the basin in the time-period we modelled, they fell from about 90,000 in 1991 to 70,000 in 2011. This can be seen as part of a wider trend, with total farmer numbers in the four basin states falling from more than 230,000 in 1976 to barely 100,000 in 2016.

It might be argued that because irrigated farms make up only a quarter of all farms, the overall numbers might mask a greater correlation between water extractions and decline in irrigated farms. While the specific impacts on irrigation farming in recent years warrant further study, there’s no signal in our data pointing to extractions making a discernible contribution to farmer numbers throughout the basin.

Modelling farmer movement

Our findings are based on a specialised data set of population and agricultural census information from statistical local areas from 1991 to 2011. We used climate risk measures from 1961 onwards.

The following infographic shows the exit pattern of farmers by local area between 1991 and 2011.



We included as many climate, economic, farming, water and socio-demographic characteristics as possible to capture historical farmer movements and create a model able to predict movements based on variables such as average temperature.

Need for a multifaceted response

Overall our modelling results suggests the most significant and largest influences on farmer exit are rising temperatures and increased drought risk, followed by the economic factors that have have been reducing the proportion of the population engaged in farming for more than a century.

Declining commodity prices, higher unemployment and urbanisation are strongly associated with farmer exit. Urbanisation, for example, has made it attractive for farmers on city fringes to sell their land to property developers and exit the industry.

Research suggests irrigators in psychological distress are more likely to want the basin plan suspended. Our research suggests their distress is probably not primarily driven by the federal government buying water entitlements from licence holders who sold them willingly. Water recovery and the basin plan is simply an easier focal point of blame than the longer-term trends making the farming lifestyle less viable.




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Nothing will be gained by focusing on short-term “fixes” at the cost of longer-term environmental harm. The problems facing all farmers cannot be addressed in isolation from longer-term global climate and economic trends.

As a society we have to decide what we value: do we want to see such a mass exodus of farmers from the land in the face of a drying climate? If not, future policy for the Basin must consider the real long-term drivers of farm exit and take a multi-faceted approach to climate change, water, land, drought and rural development.The Conversation

Sarah Ann Wheeler, Professor in Water Economics, University of Adelaide

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

Paddling blind: why we urgently need a water audit



There’s broad support from communities and farmers for proper water audits.
John/Flickr, CC BY-SA

Quentin Grafton, Crawford School of Public Policy, Australian National University and John Williams, Australian National University

In the wake of a damning royal commission and an ABC Four Corners investigation, the federal government has created an Inspector General for the Murray-Darling Basin, to combat water theft, ensure water recovery and efficiency projects are delivered properly, and essentially make sure everyone is acting as they should.

While this is a laudable aim, the Inspector General – currently former Australian Federal Police Commissioner Mike Keelty – cannot hope to do this job without knowing how much water is being used in the Basin, by whom it is used, and where.




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This might seem like basic information, but the Bureau of Meteorology, the Murray-Darling Basin Authority and state water accounts are not up to the task.

We urgently need a comprehensive audit to track the water in the Murray Darling Basin, so Inspector General Keelty can effectively investigate what he has already described as a “river ripe for corruption”.

Up the creek

Back in 2004 all governments in Australia agreed to track and provide information on water in terms of planning, monitoring, trading, environmental management, and on-farm management.

But water accounts still lack many essential features including double-entry accounting. When applied to water, double-entry accounts means that when one person consumes more water, someone else must consume less.




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The technology to track this already exists: satellites that can quantify surface water are successfully being used used in the United States.

If we had monthly water consumption measurements, we could see how much water is being used, by whom, when and where. This would help decision makers see problems before they emerge, such as the mass fish deaths in the Darling River, and respond in real time.

As a recent report from the Natural Resources Commission shows, without proper accounting, too much water is taken upstream – seriously harming downstream communities.

Wide support for an audit

An independent Basin-wide water audit is supported by communities and some irrigators.

In July NSW farmers voted in support of a federal royal commission into “the failings of the Murray Darling Basin Plan”. In our view, this vote shows many farmers support much greater transparency about how much water is being consumed, and by whom.




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Double-entry water consumption accounts would help identify whether the billions of dollars planned in subsidies to increase irrigation efficiency will actually deliver value for money. But irrigation improvements only generate public benefits when more water is left or returns to flow in streams and rivers. Such flows are essential to healthy rivers and sustainable Basin communities.

Irrigators’ crops benefit from increased efficiency, so subsidies help farmers greatly – but it is very unclear whether they do anything for the public good. In fact, they seem to reduce the amount of water that finds its way back into the rivers. Research also shows infrastructure subsidies to improve irrigation efficiency typically increases water consumption at the Basin level.

Our research, published earlier this year in the Australasian Journal of Water Resources shows federal irrigation infrastructure subsidies may have reduced net stream and river levels. This is even after accounting for the water entitlements irrigators provided to the government in exchange for these subsidies.




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Independent audits

Just like financial accounts, water accounts must be independently audited.

For the average taxpayer, who has to justify every dollar they get from the government, it’s hard to imagine how some corporations can be given millions of dollars in subsidies without actual measurements (before and after) of the claimed water savings.

If Newstart recipients need to report and manage their income and have a job plan, as part of a system of appropriate checks and balances, shouldn’t the Australian government also be checking whether billions spent on subsidies for irrigators actually saves water?




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A water audit would cost less than 1% of the money already spent on water infrastructure subsidies in the Basin. Unlike irrigation infrastructure subsidies, a water audit is value for money.

Importantly, independent water consumption accounts would allow the Inspector General for the Murray-Darling Basin to effectively manage our most critical nature resource, water.The Conversation

Quentin Grafton, Director of the Centre for Water Economics, Environment and Policy, Crawford School of Public Policy, Australian National University and John Williams, Adjunct Professor Environment and Natural Resources, Crawford School of Public Policy, Australian National University

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

The Murray-Darling Basin scandal: economists have seen it coming for decades


John Quiggin, The University of Queensland

Nations behave wisely, Israeli foreign minister Abba Eban observed five decades ago, “once they have exhausted all other alternatives”.

One can only hope that proves the case with water policy in Australia’s Murray-Darling Basin, the nation’s largest river system and agricultural heartland.




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The ABC’s Four Corners program Cash Splash, aired last night, illustrates how thoroughly we are exhausting the options that don’t work to keep rivers being sucked dry by irrigators. Billions of dollars have been spent on infrastructure schemes that have failed to deliver any measurable improvement in water flows or the state of the environment.

The Murray–Darling Basin is Australia’s largest and most complex river system. With 77,000 km of rivers, it is the food bowl of the nation.
Murray–Darling Basin Authority

This failure is no surprise to economists who have studied the problems of the Murray-Darling Basin for decades.

The central problem is well understood, as are the workable (and unworkable) possible responses.

The basin covers four states: Queensland, New South Wales, Victoria and South Australia. All state governments have allocated permits to extract water for human uses (irrigated agriculture and urban water). The allocations grew rapidly in the second half of the 20th century, exceeding the sustainable capacity of the natural environment.

One sign of the failure became dramatically obvious in 1991, with an outbreak of toxic blue-green algae over 1,200 km of the Darling River. Algal blooms are fed by nitrogen and other nutrients in fertiliser runoff and sewerage. They continue to occur.

This event underlined the need to leave enough water in rivers for “environmental flows” to keep the system healthy.

Acting with what now seems like impressive promptness, the Murray-Darling Basin Ministerial Council (made up of the water resources ministers from the basin states, the Australian Capital Territory and the federal government) imposed a cap on water extractions in 1995. It limited extractions to the volume of water capable of being taken out by the infrastructure (pumps, dams, channels, management rules) that existed in 1993-94.

The cap was supposed to be a temporary measure. It wasn’t intended to solve the problem, just stop it getting any worse in the short run.

The long-term solution was to be a system of trade in water rights, introduced by the Council of Australian Governments in 1994. Combined with the right price signals from environmental purchases, this system was meant to allocate water to its most productive uses while reducing extractions to sustainable levels.

A quarter-century on, the cap is only now being phased out, and a vast array of measures have come and gone, including the National Water Initiative, the Water Act of 2007, Water for the Future and the Murray-Darling Basin Plan.

Buying block

The failure of these initiatives rests on one simple fact: the refusal of irrigation lobby groups to countenance the government buying water rights on the open market to increase environmental flows. Their opposition has been immovable, despite many individual irrigators being keen to sell their water rights and use the money to invest in alternative cropping activities or retire.

On the other hand, there are a lucky (often politically well-connected) few who have done very well from “strategic” purchases of water. Investigative journalist Michael West has noted the National Party’s Barnaby Joyce has been publicly hostile towards buybacks of water entitlements but authorised, as federal water resources minister, three major “strategic purchases”.

Instead of water purchases, politicians like Joyce have put their faith in subsidies to infrastructure, to improve the efficiency of water use.

The idea has a lot of intuitive appeal. If less water can be used, it should be possible to increase flows in the river system without reducing agricultural output. With rare exceptions, this appealing vision has dominated the thinking of politicians and much of the public.

The reality is sadly different. The failure of infrastructure-based water recovery was both predictable and predicted.




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I pointed out the main difficulties in a piece for ABC Online in 2012. The article didn’t contain any remarkable insights. It simply stated views shared by every independent economist who has worked on the issue.

The illusion of efficiency

Among the many problems with infrastructure schemes, two have stood out.

First, the measured cost of saving water through infrastructure schemes is two to three times as much as that of buying water on the open market.

Second, and more importantly, much of the supposed water savings are illusory. Much of the water “wasted” in irrigation systems is not lost to the environment. Most of the water leakage and seepage from irrigation channels eventually returns to rivers through groundwater systems. So “saving” this water through infrastructure efficiency doesn’t actually add anything more to environmental flows.

My 2012 analysis assumed a scientifically based effort to secure water savings at the lowest possible cost to the public. As the Four Corners report has shown, that assumption was massively over-optimistic. In reality, the scheme has been characterised by lax monitoring, cronyism and rorting.




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After the expenditure of billions in public money, the system may be worse off than before. As a result, environmental disasters keep on happening.

Along with recurring algal outbreaks, we are witnessing disasters such as the massive fish kills like that in western New South Wales in January. The massive fish kills have been attributed to little or no flow in the Darling River combined with plunges from high temperatures, starving the water of oxygen.

Hundreds of thousands of dead fish in waterways around Menindee, far-west New South Wales, in January 2019.
Graeme McCrabb/AAP

As the riverine environment keeps deteriorating, there’s no sign of any positive change in policy.

Eventually, though, we must hope Abba Eban will be proved right. Having exhausted all the options that don’t work, we will have to turn to those that do.The Conversation

John Quiggin, Professor, School of Economics, The University of Queensland

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

Billions spent on Murray-Darling water infrastructure: here’s the result


Q J Wang, University of Melbourne and Avril Horne, University of Melbourne

Earlier this year, researchers suggested the amount of water returned to the Murray Darling Basin under a federal program has been “grossly exaggerated”, to the tune of hundreds of billions of litres.

The report argued that government investment in irrigation improvements might even result in a net loss of water for the environment.




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To investigate these claims, the Murray Darling Basin Authority commissioned us to undertake an independent review to examine the best available data for every irrigation efficiency project funded across the basin.

We found the government investment into irrigation efficiency projects has achieved 85% of the 750 gigalitres per year target. The remaining 15% of the target may be affected by unintended side-effects.

This result highlights the need for continued review of risks to the basin plan, as Australia grapples with the management of an extraordinary complex natural system.

How is water for the environment recovered?

The Water Act 2007 introduced significant reforms aimed at setting aside more water for the environment. At the time, record high levels of surface water were being consumed. Aiming to save 2,750 gigalitres of surface water (water flowing in the open air, rather than underground) the federal government began buying back water rights and investing in more efficient infrastructure.

The Commonwealth is providing A$3.1 billion to buy these water rights, of which A$2.5 billion has been spent. It is also providing more than A$8 billion for modernising infrastructure and water efficiency improvements, of which more than A$4 billion has so far been spent.

These projects aim to improve water delivery – reducing leaks and evaporation – and make irrigation more efficient. The water saving generated from these projects is shared between the governments for environmental use, and irrigators.

Mass fish deaths earlier in the year raised serious concerns about the health of the Murray-Darling system.
DEAN LEWINS/AAP

What are “return flows”?

To understand why the government investment in irrigation efficiency projects have not achieved 100% of the original target, we need to talk about return flows.

When water is diverted from the river for irrigation, not all of it gets consumed by the plants. Some water will make its way back to the river. This is called return flow. A large part of the return flow is through groundwater to the rivers, and this part is extremely difficult to measure. More efficient infrastructure and irrigation generally means less return flow to the river.

If these reductions are not considered when calculating the water savings, it is possible there will be implications for irrigators, the environment and other water users downstream, that previously benefited from return flows.

What we tried to determine is how much the efficiency projects reduced return flow.




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Are the water savings real?

For the first time, we attempted to bring together data on individual projects in order to assess return flows across the basin. We developed a framework for calculating return flows, which took into account water in the rivers, groundwater, and efficiency projects.

This is the first attempt to bring together the existing data on individual projects to assess return flows in the basin at a detailed level. A large portion of the data used in this study was collated for the first time and not previously available in a readily accessible format.

We found a reduction in return flow of 121 gigalitres per year as a result of the government funded projects. This is comparable to 16% of the recovery transferred to environmental entitlements.

What does this mean for the Basin Plan?

There are several important details that must be considered to assess the importance of the return flow volume for the environment and Basin Plan objectives. We do not attempt here to quantify the outcomes, but instead to raise a number of important considerations beyond simply “volume”.

1. Recovered water should be legally protected

Return flows are good for the environment, but are essentially accidental. As irrigation becomes more efficient, inevitably they will diminish.

On the other hand, formally allocated environmental water entitlements are legally protected. It is more secure for the environment – and far easier to keep track of.

2. It’s not ‘efficiency vs the environment’

Part of this debate centres around the idea that reducing return flows means less water for the environment. But in Victoria and New South Wales, before water is allocated to anyone (irrigators or the environment), a base level is set aside. This is the minimum required to keep the rivers physically flowing and to meet critical human needs.

Efficiency projects mainly affect this base-level flow of the river. This means the water reduction is shared across everyone who holds a water licence – the majority of which are irrigators.

This policy means it does not make sense to compare the effect of efficiency projects directly with the recovery of environmental water.

3. Volume is a crude measure of environmental benefit

The focus of the debate around return flows has been based on the annual volume of returned environmental water in comparison to the stated Basin Plan target.

However, the real objective of the water recovery is to achieve environmental objectives in the Basin. This is not just about annual volumes, but the quantity, timing, and quality of fresh water.

How should we move forward?

Our review has particularly highlighted the need for better ongoing data collection and regular evaluations.




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Both taxpayer investments and the water market are changing irrigation to become more efficient and reducing the river’s base flow. With this in mind, we need to regularly reexamine how we share water between everyone (and everything) that needs it, particularly in extended dry periods.

The Murray-Darling Basin is a constantly changing system, both in terms of climate and irrigation. Return flows are one of a number of potential threats to the Basin Plan. As the system is continually changing, these threats will need to be reassessed with each Basin Plan review.


A Four Corners program on the $13 billion Murray-Darling Basin Plan will air on ABC at 8.30pm on July 8.

This article was co-written by Glen Walker, a former CSIRO employee and now private consultant, who worked with the University of Melbourne on the independent review.The Conversation

Q J Wang, Professor, University of Melbourne and Avril Horne, Research fellow, Department of Infrastructure Engineering, University of Melbourne

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