Last summer’s fish carnage sparked public outrage. Here’s what has happened since



Graeme McCrabb/AAP

Lee Baumgartner, Charles Sturt University and Max Finlayson, Charles Sturt University

As this summer draws to a close, it marks just over a year since successive fish death events at Menindee in Lower Darling River made global headlines.

Two independent investigations found high levels of blue-green algae and low oxygen levels in the water caused the deaths. Basically, the fish suffocated.




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The conditions were caused by a combination of water extraction and extremely dry conditions which effectively stopped the river from flowing. Both investigations concluded that until more water flowed in the Darling, in western New South Wales, further fish kills were very likely.

So what’s happened since, and does the recent rain mean the crisis won’t be repeated?

Federal and state government action

In April last year the federal government committed A$70 million to improve the river’s health and prevent more fish deaths. Let’s examine what’s been done so far:

– Native fish management and recovery strategy: Parts of a draft native fish management and recovery strategy have been released for public consultation. The plan has included governments, academics, the community and indigenous groups.

– Native fish hatchery: Government hatchery facilities at Narrandera in NSW will be upgraded to hold and breed more fish. But reintroducing fish into affected areas is challenging and could be a decades-long program.

– Research: The government committed to new research into hydrology and climate change. A panel has been formed and the oversight committee is scoping the most effective research outcomes to better manage water under a changed climate.

– Fish passage infrastructure: Fish ladders – structures that allow fish to travel around obstacles on a river – are needed at sites on the lower and upper Darling. Fish ladder concept designs have progressed and are also part of the NSW government’s Western Weirs project.

-In-stream cameras: Live-stream feeds of the Darling River are not yet available.

-Meter upgrades and water buybacks: Discussions have begun as part of a commitment to buy back A-class water licenses from farmers and return water to the rivers. Rollout of improved metering is due over the next five years.

Progress on these actions is welcome. But the investigation panels also recommended other actions to help fish populations recover over the long term, including ensuring fish habitat and good water quality.

Further fish deaths

In 2003, basin native fish communities were estimated to be at 10% of pre-European levels and the spates of fish deaths will have reduced this further.

Over spring and summer in 2019, conditions in the Darling River deteriorated. A series of smaller, but significant, fish deaths prompted government agencies and communities to conduct emergency “fish translocations”.. Aerators were deployed in a bid to improve the de-oxygenation. Fish were moved to more suitable water bodies, or to hatcheries to create insurance populations.

By spring, once-mighty rivers such as the Darling and Macquarie had dried to shallow pools. As summer progressed, more than 30 fish die-offs occurred in the Macquarie, Namoi, Severn, Mehi and Cudgegong rivers and Tenterfield Creek.

What about the rain?

Strong recent rainfall means upper parts of the Darling catchment are now flowing for the first time in more than two years. Flows are passing over the Brewarrina Weir and associated fishway.

A flowing Darling is great, but it raises questions over future water management. Farmers have been waiting for years for the Darling to flow and will be eager to extract water for agricultural productivity. Likewise, the environment has been awaiting a “flush” to reset the system and restore ecological productivity.




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After the rains, the NSW government allowed irrigators to harvest floodwaters to reduce the threat of damage to private infrastructure. Now that threat has subsided, governments are working together to “actively manage” the event – meaning water rules will be decided as the flow progresses, in consultation with water users and environmental managers.

But there is still significant debate on how best to manage water over the longer term.

Water use on the Darling River remains highly contested.
Dean Lewins/AAP

Is a flowing Darling a return to normal?

The current flows in the Darling are far from a return to normal conditions. NSW is still in drought, and the river flows are yet to reach the Lower Darling. Many children in the Menindee township have not seen a flowing Darling in their lifetime.

Indigenous elders and recreational fishers – those who remember when the river flowed freely and was full of fish – are lamenting the recent declines. In parts of the system, dry riverbeds and isolated pools are still begging to be connected so fish can move about, spawn, and naturally recover.




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River flows could take up to six weeks to reach the lower Darling, and follow-up rain is urgently needed to avoid another summer of fish carnage. Future water sharing strategies must protect both upstream and downstream communities. Some people are lobbying for the Menindee lakes to be listed as internationally important under the Ramsar Convention on Wetlands to ensure biodiversity and water management work together.

Undoing over 200 years of fish declines will require a sustained effort, with a significant investment in recovery actions over a long period. We must recognise Australia is a country of long droughts and flooding rains, and develop a proactive native fish strategy that reduces the probability of a similar disaster in future.

But unfortunately, as history has shown that when we transition from drought to flood, our memories can be short.The Conversation

Lee Baumgartner, Professor of Fisheries and River Management, Institute for Land, Water, and Society, Charles Sturt University and Max Finlayson, Adjunct Professor, Charles Sturt University

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

Heavy rains are great news for Sydney’s dams, but they come with a big caveat


Ian Wright, Western Sydney University and Jason Reynolds, Western Sydney University

Throughout summer, Sydney’s water storage level fell alarmingly. Level 2 water restrictions were imposed and the New South Wales government prepared to double the capacity of its desalination plant.

But then it began to rain, and rain. Sydney water storages jumped from 41% in early February to 75% now – the highest of any capital city in Australia.

This is great news for the city, but it comes with a big caveat. Floodwaters will undoubtedly wash bushfire debris into reservoirs – possibly overwhelming water treatment systems. We must prepare now for that worst-case pollution scenario.

Reservoirs filled with rain

The water level of Sydney’s massive Lake Burragorang – the reservoir behind Warragamba Dam – rose by more than 11 meters this week. Warragamba supplies more than 80% of Sydney’s water.

Other Sydney water storages, including Nepean and Tallowa dams, are now at 100%.
WaterNSW report that 865,078 megalitres of extra water has been captured this week across all Greater Sydney’s dams.

This dwarfs the volume of water produced by Sydney’s desalination plant, which produces 250 megalitres a day when operating at full capacity. Even at this rate, it would take more than 3,400 days (or nine years) to match the volume of water to added to Sydney’s supply this week.

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The Warragamba Dam before the drought and after the recent heavy rains.

But then comes the pollution

Thankfully, the rain appears to have extinguished bushfires burning in the Warragamba catchment for months.

But the water will also pick up bushfire debris and wash it into dams.

Over the summer, bushfires burnt about 30% of Warragamba Dam’s massive 905,000 hectare water catchment, reducing protective ground cover vegetation. This increases the risk of soil erosion. Rain will wash ash and sediment loads into waterways – adding more nitrogen, phosphorous and organic carbon into water storages.




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Waterways and ecosystems require nutrients like phosphorous and nitrogen, but excess nutrients aren’t a good thing. They bring contamination risks, such as the rapid growth of toxic blue-green algae.

Drinking water catchments will always have some degree of contamination and water treatment consistently provides high quality drinking water. But poor water quality after catchment floods is not without precedent.

We’ve seen this before

In August 1998, extreme wet weather and flooding rivers filled the drought-affected Warragamba Dam in just a few days.

This triggered the Cryptosporidium crisis, when the protozoan parasite and the pathogen Giardia were detected in Sydney’s water supplies. It triggered health warnings, and Sydneysiders were instructed to boil water before drinking it. This event did not involve a bushfire.




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The Canberra bushfires in January 2003 triggered multiple water quality problems. Most of the region’s Cotter River catchments, which hold three dams, were burned. Intense thunderstorms in the months after the bushfire washed enormous loads of ash, soil and debris into catchment rivers and water reservoirs.

This led to turbidity (murkiness), as well as iron, manganese, nitrogen, phosphorus and carbon in reservoir waters. The inflow of organic material also depleted dissolved oxygen which triggered the release of metals from reservoir sediment. At times, water quality was so poor it couldn’t be treated and supplied to consumers.

The ACT Government was forced to impose water restrictions, and built a A$38 million water treatment plant.

Have we come far enough?

Technology in water treatment plants has developed over the past 20 years, and water supply systems operates according to Australian drinking water guidelines.

Unlike the 1998 Sydney water crisis, WaterNSW, Sydney Water and NSW Health now have advanced tests and procedures to detect and manage water quality problems.

In December last year, WaterNSW said it was aware of the risk bushfires posed to water supplies, and it had a number of measures at its disposal, including using booms and curtains to isolate affected flows.

However at the time, bushfire ash had already reportedly entered the Warragamba system.

The authors crossing the Coxs River during very low flow last September.
Author provided

Look to recycled water

Sydney’s water storages may have filled, but residents should not stop saving water. We recommend Level 2 water restrictions, which ban the use of garden hoses, be relaxed to Level 1 restrictions which ban most sprinklers and watering systems, and the hosing of hard surfaces.

While this measure is in place, longer term solutions can be explored. Expanding desalination is a popular but expensive option, however greater use of recycled wastewater is also needed.




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Highly treated recycled water including urban stormwater and even treated sewage should be purified and incorporated into the water supply. Singapore is a world leader and has proven the measure can gain community acceptance.

It’s too early to tell what impact the combination of bushfires and floods will have on water storages. But as extreme weather events increase in frequency and severity, all options should be on the table to shore up drinking water supplies.The Conversation

Ian Wright, Senior Lecturer in Environmental Science, Western Sydney University and Jason Reynolds, Senior Lecturer in Geochemistry, Western Sydney University

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

Fire almost wiped out rare species in the Australian Alps. Feral horses are finishing the job



Feral horses are destroying what little threatened species habitat was spared from bushfire.
Invasive Species Council

Jamie Pittock, Australian National University

On Friday I flew in a helicopter over the fire-ravaged Kosciuszko National Park. I was devastated by what I saw. Cherished wildlife species are at grave risk of extinction: those populations the bushfires haven’t already wiped out are threatened by thousands of feral horses trampling the land.

The New South Wales park occupies the highest mountain range in Australia and is home to plants and animals found nowhere else in the world. Many of these species are threatened, and their survival depends on protecting habitat as best we can.




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Kosciuszko National Park provides habitat for two species of corroboree frog (critically endangered), the alpine she-oak skink (endangered), broad-toothed rat (vulnerable) and stocky galaxias (a critically endangered native fish), among other threatened species.

As the climate has warmed, the cool mountain habitat of these species is shrinking; bushfires have decimated a lot of what was left. Feral horses now threaten to destroy the remainder, and an urgent culling program is needed.

Devastation as far as the eye can see on the burnt western face of Kosciuszko National Park.
Jamie Pittock

Not a green leaf in sight

Australia’s plants and ecosystems did not evolve to withstand trampling by hard-hooved animals, or their intensive grazing. Unfortunately, the New South Wales government has allowed the population of feral horses in the park to grow exponentially in recent years to around 20,000.

I flew over the northern part of the park with members of the Invasive Species Council, who were conducting an urgent inspection of the damage. Thousands of hectares were completely incinerated by bushfires: not a green leaf was visible over vast areas. A cataclysm has befallen the western face of the mountains and tablelands around Kiandra and Mount Selwyn.




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Further north and east of Kiandra the fires were less intense and burnt patchily. On Nungar Plain the grassland and peat wetlands were only lightly burnt, and the first green shoots were already visible along the wetlands of the valley floor.

At first, I wondered if the fires may have spared two animals which live in tunnels in the vegetation on the sub-alpine high plains: the alpine she-oak skink and broad-toothed rat (which, despite the name is a cute, hamster-like creature).

The hamster-like broad toothed rat.
Flickr

But not only was their understory habitat burnt, a dozen feral horses were trampling the peat wetlands and eating the first regrowth.

On the unburnt or partially burnt plains a few ridges over, 100 or more horses were mowing down the surviving vegetation.

Precarious wildlife refuges

Next we flew over a small stream that holds the last remaining population of a native fish species, the stocky galaxias. A small waterfall is all that divides the species from the stream below, and the jaws of the exotic trout which live there.

The aftermath of the fires means the last refuge of the stocky galaxias is likely to become even more degraded.

Over the years, feral horses have carved terraces of trails into the land causing erosion and muddying the stream bank. As more horses congregate on unburnt patches of vegetation after the fires, more eroded sediment will settle on the stream bed and fill the spaces between rocks where the fish shelter. Ash runoff entering the stream may clog the gills of the fish, potentially suffocating them.

An Alpine she-oak skink.
Renee Hartley



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Many key wetland habitats of the southern and northern corroboree frogs have also been burnt. These striking yellow and black frogs nest in wetland vegetation.

A corroboree frog.
Flickr

We hovered over a key wetland for the northern corroboree frog that had not been burnt, deep in the alpine forest. A group of feral horses stood in it. They had created muddy wallows, trampled vegetation and worn tracks that will drain the wetland if their numbers are not immediately controlled.

Horses out of control

Five years ago a survey reported about 6,000 feral horses roaming in Kosciuszko National Park. By 2019, the numbers had jumped to at least 20,000.

We saw no dead horses from the air. Unlike our native wildlife, most appear to have escaped the fires.




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Flying down the upper Murrumbidgee River’s Long Plain, I saw large numbers of feral horses gathered in yet more wetlands. Displaced by the fires to the south and west, they were already trampling the mossy and heathy wetlands that store and filter water in the headwaters.

The Murrumbidgee River is a key water source for south-east Australia. The horses stir up sediment and defecate in the water. They create channels which drain and dry the wetlands, exposing them to fire.

One-third of Kosciuszko National Park has been burnt out and at the time of writing the fires remain active. Feral horses are badly compounding the damage.

If we don’t immediately reduce feral horse numbers, the consequences for Kosciuszko National Park and its unique Australian flora and fauna will be horrendous.

Responsible managers limit the numbers of livestock on their lands and control feral animals. The NSW government must repeal its 2018 legislation protecting feral horses in Kosciuszko National Park, and undertake a responsible control program similar to those of the Australian Capital Territory and Victorian governments.

Without an emergency cull of feral horses in Kosciuszko National Park, burnt vegetation may not fully recover and threatened species will march further towards extinction.The Conversation

Jamie Pittock, Professor, Fenner School of Environment & Society, Australian National University

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

‘The size, the grandeur, the peacefulness of being in the dark’: what it’s like to study space at Siding Spring Observatory



Today we hear about some of the fascinating space research underway at Siding Spring Observatory – and how, despite gruelling hours and endless paperwork, astronomers retain their sense of wonder for the night sky.
Shutterstock

Cameron Furlong, The Conversation and Sunanda Creagh, The Conversation

How did our galaxy form? How do galaxies evolve over time? Where did the Sun’s lost siblings end up?

Three hours north-east of Parkes lies a remote astronomical research facility, unpolluted by city lights, where researchers are collecting vast amounts of data in an effort to unlock some of the biggest questions about our Universe.

Siding Spring Observatory, or SSO, is one of Australia’s top sites for astronomical research. You’ve probably heard of the Parkes telescope, made famous by the movie The Dish, but SSO is also a key character in Australia’s space research story.

In this episode, astrophysics student and Conversation intern Cameron Furlong goes to SSO to check out the huge Anglo Australian Telescope (AAT), the largest optical telescope in Australia.

Siding Spring Observatory, north east of Parkes.
Shutterstock



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And we hear about Huntsman, a new specialised telescope that uses off-the-shelf Canon camera lenses – a bit like those you see sports photographers using at the cricket or the footy – to study very faint regions of space around other galaxies.

Students use telescopes to observe the night sky near Coonabarabran, not far from SSO.
Cameron Furlong

Listen in to hear more about some of the most fascinating space research underway in Australia – and how, despite gruelling hours and endless paperwork, astronomers retain their sense of wonder for the night sky.

“For me, it means remembering how small I am in this enormous Universe. I think it’s very easy to forget, when you go about your daily life,” said Richard McDermid, an ARC Future Fellow and astronomer at Macquarie University.

“It’s nice to get back into it to a dark place and having a clear sky. And then you get to remember all the interesting and fascinating things, the size, the grandeur and the peacefulness of being in the dark.”

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Additional audio

Kindergarten by Unkle Ho, from Elefant Traks.

Lucky Stars by Podington Bear from Free Music Archive.

Slimheart by Blue Dot Sessions from Free Music Archive.

Illumination by Kai Engel from Free Music Archive.

Phase 2 by Xylo-Ziko from Free Music Archive.

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Pure Water by Meydän, from Free Music Archive.

Images

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Cameron Furlong




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The Conversation


Cameron Furlong, Editorial Intern, The Conversation and Sunanda Creagh, Head of Digital Storytelling, The Conversation

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.

Fish kills and undrinkable water: here’s what to expect for the Murray Darling this summer



Dry conditions will make for a difficult summer in the Murray Darling Basin.
AAP/Dean Lewins

Jamie Pittock, Australian National University

A grim summer is likely for the rivers of the Murray-Darling Basin and the people, flora and fauna that rely on it. Having worked for sustainable management of these rivers for decades, I fear the coming months will be among the worst in history for Australia’s most important river system.

The 34 months from January 2017 to October 2019 were the driest on record in the basin. Low water inflows have led to dam levels lower than those seen in the devastating Millennium drought.

No relief is in sight. The Bureau of Meteorology is forecasting drier-than-average conditions for the second half of November and December. Across the summer, rainfall is also projected to be below average.

So let’s take a look at what this summer will likely bring for the Murray Darling Basin – on which our economy, food security and well-being depend.

A farmer stands in the dry river bed of the Darling River in February this year.
Dean Lewins/AAP

Not a pretty picture

As the river system continues to dry up and tributaries stop flowing, the damaging effect on people and the environment will accelerate. Mass fish kills of the kind we saw last summer are again likely as water in rivers, waterholes and lakes declines in quality and evaporates.

Three million Australians depend on the basin’s rivers for their water and livelihoods. Adelaide can use its desalination plants and Canberra has enough stored water for now. But other towns and cities in the basin risk running out of water.




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Governments were warned well before the drought to better secure water supplies through infrastructure and other measures. But the response was inadequate.

Some towns such as Armidale in New South Wales have been preparing to truck water to homes, at great expense. Water costs will likely increase to pay for infrastructure such as pumps and pipelines. The shortages will particularly affect Indigenous communities, pastoralists who need water for domestic use and livestock, irrigation farmers and tourism business on the rivers.

Water in major storages as reported at 13 November 2019.
Murray Darling Basin Authority

As we saw during the Millennium drought, when wetland soils dry some sediments will oxidise to form sulfuric acid. This kills fauna and flora and can make water undrinkable.

Red gum floodplain forests and other wetland flora will continue to die. Most of these wetlands have not had a drink since 2011. The desiccation, due to mismanagement and drought, is likely to see the return of hypersalinity – a huge excess of salt in the water – with river flows too weak to flush the salt out to sea.




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If drought-breaking rains do come, as they did in 2010-11, this would create a new threat. Floodwaters would inundate leaf litter on the floodplains, triggering a bacterial feast that depletes the water of oxygen. These so-called “blackwater” events kill fish, crayfish and other aquatic animals.

The risk of blackwater events has largely arisen because government authorities have failed to manage water as they had agreed. In particular, the NSW and Victorian governments have not worked with farmers to allow managed river flows to inundate floodplains.

The prospect of thousands of dead fish in the Murray Darling Basin looms large again this summer.
AAP/GRAEME MCCRABB

How did we get here?

The severity and impacts of this drought should not come as a surprise. In the 1980s, the CSIRO’s first projections of climate change impacts in the basin foreshadowed what is unfolding now.

Despite the decades-old warnings, water management authorities in some catchments favoured water extraction by irrigators over rural communities, pastoralists and the environment. For example, the NSW Natural Resources Commission in September found that state government changes to water regulations brought forward the drying up of the Darling River by three years.




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Since the basin plan was adopted in 2012 our federal and state political leaders have reduced the volume of real water needed to keep the rivers healthy, supply water to people and flush salt out to sea. For example, in May 2018 the federal government and Labor opposition agreed to reduce water allocated to the environment by 70 billion litres a year on average, without a legitimate scientific basis.

The basin plan is based on historical river flow records, without explicitly allowing for diminished inflows resulting from climate change. Australian water management has followed what’s been termed a “hydro-illogical cycle” where drought triggers reform, but government leaders lose attention once it rains. This suggests meaningful reform must be implemented when drought is occurring and politicians are under pressure to respond.

Severe drought and mismanagement means a dire summer for the Murray-Darling river system.
Dean Lewins/AAP

How to fix this

Governments must assume that climate-induced drought conditions in the basin are the new normal, and plan for it.

Action should include:

  • Revising water allocations consistent with climate change projections

  • Investing in managed aquifer recharge to supply more towns with reliable and safe water

  • Restoring rivers by reallocating enough water to sustain their health

  • Increasing wetland resilience by reconnecting rivers to their floodplains in wetter years

  • Improving river health, such as by fencing out livestock.

Investing in these adaptation actions now would provide jobs during the drought and prepare Australia for a much drier future in the Murray-Darling Basin.The Conversation

Jamie Pittock, Professor, Fenner School of Environment & Society, Australian National University

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