In Australia, the line between drought and flood feels like it can change in the blink of an eye.
As the water arrives, parched, barren land is transformed into oases teeming with life.
This is on full display in central west New South Wales at Burrendong Dam, which at capacity can hold 1.6 million megalitres of water — three times as much water as Sydney Harbour.
Using data captured from satellites, we're able to see the extent of water at the dam when it was full back in November 2016.
But over the next three years, drought took hold.
The 2017 to 2019 period was the hottest and driest three-year stretch ever recorded for the Murray-Darling Basin.
It reduced this once-flourishing lake to less than 2 per cent of capacity.
But in 2020 the drought started to ease.
Huge downpours saw the dam go from 17,000 megalitres of available water, to more than 1.6 million megalitres near the end of 2021.
While the rain has been devastating for so many, for the communities and habitats reliant on the dam, it also brought with it life.
Water released from Burrendong flows up the Macquarie River, providing a number of rural towns with a much-needed water supply.
Farmers also draw from this valuable water resource for irrigated agriculture.
In 2020, environmental flows started being released down the Macquarie River for the first time in years.
Those flows were, in part aimed at restoring the 200,000-hectare Macquarie Marshes — one of the country's largest remaining semi-permanent inland wetlands — recognised by the Ramsar Convention on Wetlands as a site of international significance.
Now after three consecutive wet years, locals say the marshes have transformed from a "moonscape" to a flourishing wetland.
Beyond the soaked Macquarie Marshes, the water continues its journey into the wider network of river systems in the Murray-Darling Basin.
It converges with the lower Barwon River, then the Darling, where it begins the journey south to the River Murray in South Australia.
As water from right across the basin makes its way into South Australia, the state is recording flow rates and river heights not seen in decades in some areas.
With it, it has brought heightened flood risk for communities. But it has also brought life to the water-starved Coorong, Lower Lakes and River Murray mouth.
Gary Hall has spent his entire life on the Macquarie Marshes.
The fourth generation farmer was born here in 1967, the same year Burrendong Dam was completed.
"During the seventies when I was a youngster here, we actually did get a good run of seasons very similar to this wet," he says.
"What we're seeing now is, for me, memories of when I was a youngster."
Hall says he's watched the landscape change over the decades influenced by upstream developments, dams and climate change.
"It's been a slow decline … changes to the landscape from influences to water regimes don't happen overnight, they're a gradual process.
"For those of us that have been here for a long period of time, your expectations are constantly reducing, because we see a small environmental flow come to the marshes."
"It's times like this that remind us that this is what it's supposed to be like."
Around 12 per cent of the Macquarie Marshes is nature reserve, but the rest is privately owned freehold land, much of which has been held by families like Gary Hall's for generations.
The most recent drought saw the marshes suffer through the driest years on record, from 2017–2019.
For Leanne Hall, who moved here 30 years ago after marrying Gary, the wet has brought birds to the marshes she's never seen before.
"It was like a moonscape, there wasn't a blade of grass, there wasn't any water in the river system. There were thousands of kangaroos dying along the river, there were no water holes left. It was absolutely devastating, with dust storms every other night."
Leanne recognises the pain of communities and neighbours upstream impacted by flooding and says it's a privilege to be on the marshes during this boom.
"It's absolutely magical to see the country transform into such a beautiful oasis.
"The wetland is a stone's throw from our kitchen window … We'll look out the kitchen window and see the straw necked ibis, the sacred ibis, the glossy ibis. They'll be foraging around on our lawn in quite large numbers, and to look out my kitchen window and see that it just makes my heart sing."
At the height of the drought, the Burrendong Dam almost ran completely dry. You could walk across the cracked, parched surface.
But Gary Hall believes it was poor management, rather than the dry, that was to blame.
"Burrendong Dam would have made it easy through the '17–20 drought if they hadn't allocated all the water to general security licence."
General security water licences are those held by irrigators. They're the last to be allocated, and how much they receive each year depends on how much water is in the system, as well as what's predicted to arrive.
Around 70 per cent of Australian water is used for irrigation depending on the year, with two-thirds of that in the Murray-Darling Basin.
Hall doesn't rely on irrigation water because he grazes cattle on the marshlands.
"For me it's a no-brainer. We really need to have a good hard look at how the water is allocated, and the answer isn't in building more dams.
"If we're serious about adapting to climate change, we need to move the environmental water holding further up the priority pyramid and we need to have a look at town water security for growing cities."
That would leave less water for irrigation.
Bill Johnson is a former director of the Murray-Darling Basin Authority (MDBA) and began his career as a park ranger on the Macquarie Marshes.
He says while irrigation began after Burrendong Dam was built, it took a while for it to really get going.
Then in the 1990s the effects of a drier climate, combined with increased irrigation, began to hit, culminating in the last drought when the dam almost ran dry.
Johnson explains that water in the Macquarie is allocated not only on the water in the system, but on projected minimum inflows.
Water that doesn't exist yet.
"They were caught out really badly this time because they allocated the water and it didn't turn up. The water that was meant to fall as rain and flow into Burrendong Dam still hadn't evaporated out of the Indian Ocean."
"You could actually allocate water based on the water that you've got in the storage, not on future anticipated inflows. But what that does is it means that there's less water allocated to irrigation.
"What I think is problematic is the slowness to adjust to changing circumstances, the denial that circumstances have changed. I think we know what to do but we are probably reluctant, as a community, to do it."
Tensions between the environment, town water security and irrigators makes water reform a difficult task.
"Water is an exceptionally complex and emotional issue and I think it's always emotional when it's people's livelihoods that are on the chopping block", says Michael Drum, executive officer of Macquarie River Food and Fibre (MRFF) which represents more than 500 irrigators.
Drum disagrees that there's a problem with how water is allocated.
"The determination is made by the amount of resource available. If we're in a drying sequence, then people who own water licences don't have the water allocated to them, it's as simple as that.
"As far as I'm concerned the current system takes account of climate change exceptionally well, given its dealing with the climate as it is now."
He believes the environment already gets its fair share.
"The system at the moment is heavily weighted towards ensuring that the environment has its water allocated to it over a forecasted period."
Although the future inflows in the Macquarie's allocations are based on the driest observed inflow levels, the NSW environment department's guide for water allocation states that the design carries a level of risk.
"In the highly unlikely event of a new record-low inflow sequence, this assumed future inflow will not have eventuated, and account water will not be supported by physical water in storage. A small risk is, therefore; taken when allocating water," the guide states.
The last drought broke all the records and future inflows have consequently been downgraded. But heat, drought and floods continue to break records as climate change intensifies.
'We've based our water policy ... on a poem'
While Australians may be familiar with the cyclical nature of droughts and floods, Bill Johnson says human made impacts combined with climate change are causing them to become more extreme.
"The land of drought and flooding rains I think is problematic because it simplifies it. It's not simple and it oversimplifies it. And it's a poem, it's funny we've based our water policy to a large extent on a poem," Johnson said, referencing Dorothea Mackellar's 1906 poem My Country.
"If what we've seen for the last really 15 to 20 years is the new norm and becomes more extreme, which is probably likely, then there'll be enormous ramifications.
"There's a lot of negotiation to come. I don't know whether everyone's really well equipped."
The impacts of water policy are felt no more keenly than at the southern end of the Murray-Darling Basin, with upstream management determining just how much water makes it through.
Downstream communities, wetlands and lakes endured prolonged suffering during the last drought. Now they're dealing with floods.
The water flowing into South Australia is the highest it's been in decades, with river levels now above the floods of 1974 in some places.
River ecologist Richard Kingsford has watched the Murray-Darling Basin through droughts and floods, surveying the system from the land and sky.
"Before 2020 most of the dams in the Murray-Darling Basin — and there are some very big dams — were empty, or almost empty, so they all had to fill.
"All of that initial water that would have gone down the river system goes into those dams to fill them up, but it's not until we get to this year, 2022, where the dams are spilling … that the effect of the dam is no longer working because they're all full.
"It's almost like we don't have any dams at the moment because whatever water falls up in those catchments basically goes down the river."
Flows into South Australia are expected to peak at the end of December, with 190 gigalitres of water a day moving across the border down the Murray.
That amount of water hasn't been seen since 1974, when about 180 gigalitres of water per day was recorded. But it's still well below the record set in 1956 of 341 gigalitres per day.
The river system has changed dramatically over time, as dams were built, irrigation and development increased and the use of flood plains changed.
And that's making it harder for authorities to predict the flows moving downstream.
"It seems a bit of a mismatch between what the flow forecasts are saying and what we're seeing on ground," says Chrissie Bloss, manager of water delivery in the South Australian Department for Environment and Water.
"That could be due to a range of reasons, local differences that have occurred since those last big floods in the 1970s, or just the challenges of measuring flow at those really big river heights."
The floods are now expected to exceed the levels seen in 1931 in some places, but Bloss says it could look very different.
"It is a little bit of a mystery at the moment, why we are seeing these differences … but we are undertaking a lot of on-site measurements. Hydrographers are out there visiting rivers, taking observations of flow, velocity and water levels.
"When this event is over, we're going to have much better information available to understand how the river floods, and what levels we're going to expect if there's future flooding."
For a long time, traditional owners up and down the basin say they've been excluded from government policies and contemporary water management.
Grant Rigney is a Ngarrindjeri man and chair of Murray Lower Darling Rivers Indigenous Nations (MLDRIN). He spent his childhood travelling and camping along the river system, following his father who worked on the railways.
"Before we had constraints in the river system, we had a free-flowing system, we had fantastic water quality.
"We've actually re-diverted a natural flowing water system, it is a living entity in its own right. People don't unfortunately see it as a living entity, they see it as a commodity, they see it as a way of making economic gain, for their own purposes."
Rigney is also critical of how water is allocated in the Murray-Darling Basin.
"How do you actually model something for future inflows?
"We could be very well in a drought within the next year and a half to two years. For all we know, with this current climate change, changing so quickly and so vastly, it's very hard to model what that would look like. And the reality is in the Murray-Darling Basin, it is an over-allocated system already.
"We have an obligation to make sure that our future generations have something to springboard off, and at this present moment they are not going to have that."
While this year's floods have provided a much-needed reset for large parts of eastern Australia, river ecologist Richard Kingsford warns that one flood doesn't fix decades of degradation.
"It's certainly a fantastic restoration process underway at the moment.
"There's no doubt that this flood will be fantastic for future generations. The question is how much of a bounce has happened."
Kingsford uses the analogy of a bouncing ball to describe the way the river would oscillate between dry and wet.
"What used to happen is we used to get quite frequent high bounces and really low bounces … and in those high bounces, the biodiversity would have taken off, and would have had enough to respond and wait for the next big boom period.
"With river regulation those bounces aren't as high because there's less water in the system and less flooding … the times when it's not bouncing, the dry times are more severe, so they're flatlining for longer."
He says small-to-moderate floods aren't nearly as extensive or as frequent as they used to be, the long-term impacts of which are yet to be determined.
While there's no doubt climate change is playing a part in those trends, Kingsford believes river regulation is having a much bigger impact.
"The impact of climate change is, if you like, a veneer on the top of river regulation.
"I think that it's a fundamental problem in terms of policy, we have to have some buffers here. Most of all, to manage these rivers so that we can provide for human health, but also for the environment.
"We can't be trying to squeeze every drop of water out of these rivers for developing and abstracting that water for irrigation."
The solution often offered up to solve Australia's water crises is to build or expand water storage, through dams and weirs.
A view shared by Michael Drum, who represents irrigators in the Macquarie valley.
"The last drought was a big hint that the infrastructure that's involved in water, from a state point of view, or a government point of view, is lacking and I think we've been slow at a policy level to address that problem.
"We'll get in the next dry sequence and we'll be having the same conversation."
But Bill Johnson says more dams doesn't mean there's more water.
"As soon as you build the dam, or enlarge a dam, you have less water because you get evaporation. Out of Burrendong the evaporation is about 10 per cent of the water so immediately you get less water for a dam.
"If you enlarge a dam, you get a bigger surface area with more shallow water, so you'll increase the evaporation.
"While you've got the same available water determination allocation policy, all that's going to happen is irrigation will have more water allocated to it because the town volumes are pretty well fixed.
"You could ensure more secure town water supplies by allocating marginally less to irrigation, just marginally less."
Adelaide water consultant Dr Erin Smith is more optimistic about how Australia is responding to the dramatic changes to water supply.
"Within the space of a very short period of time, we've gone from one extreme to the next and I think we are learning how to manage between such large swings and that variability within the Australian climate, as well as with the challenges and uncertainties of climate change.
"Even though there is a lot of water around, and water shortage is not the problem, we are seeing continued emphasis on being able to improve and continue to adapt to changing water supply."
Smith says it's critical governments maintain a long-term perspective when it comes to water resource planning and water security.
But for now she believes the large amount of water in storage will offer some reprieve for communities hit by back-to-back disasters.
"Communities are under a lot of pressure at the moment, there's going to be a period of recovery … but certainly with the volumes of water held in storage, there will be a couple of years with very strong allocations to entitlements.
"We will go back into a dry period at some point and with water in the storages, things are very well placed to be able to manage through the first part of that dry cycle."
Back on the Macquarie Marshes, Gary Hall reflects on the last decade of extremes he's had to endure on his farm.
"The big picture is, as a farmer, when you experience a time like that, you want to try and put principles in place to avoid the event of that scale happening again."
Hall is hyper-aware that despite the wet, the next dry is coming.
"We all know, for all of us that live on the land, that it's coming, we've got to be better at adapting.
"I'm sure individual farmers have learnt the lesson, nothing like having a business kicked in the guts, but as far as society, no I don't think so.
"I actually think farmers in general are pretty accepting nowadays of climate change — our droughts getting bigger and our floods are getting bigger. At a local level, I think there's a lot of investment in preparing for these wild fluctuations Mother Nature's throwing at us, but at a government level … no I don't think it's being addressed at all."
Credits:
Reporting: Jess Davis
Digital production/Graphics: Mark Doman
Animation: Jack Fisher
Development: Katia Shatoba, Thomas Brettell
Additional design: Alex Palmer
Notes about the data used in this story:
In the header animation, the extent of water in Burrendong Dam was captured using Geoscience Australia's historical water observation data. We then used an algorithm to convert GA's satellite data into vector format.
