"I've been forced to bathe my baby with bottled water." The human cost of the Darling River crisis.

Each night, like millions of parents around Australia, Lauren Blunden prepares a bath for her child. But the water she lathers over seven-month-old Will’s beautifully soft skin is more precious than most. It’s rain water, taken from her family’s fast-dwindling tank.

Lauren, 28, lives with her husband Matt on Tolarno Station, a 500,000 acre patch of land on the ailing Darling River in far western New South Wales. The river water that supplies their home is now running brown through their taps, too toxic to drink or touch. And it’s been that way since before Christmas.

“It’s pure filth. It’s absolutely disgusting. You turn on one tap and it fills your house with a rotten smell, like sewage,” she told Mamamia. “It’s terrifying. I keep thinking, what if [Will] gets sick? It’s devastatingly frightening.”

They are just one of the families affected by the water crisis unfolding in the region, where the collapse of the river system has resulted in toxic algae blooms that have destroyed millions of fish and affected residents’ water supply.

Over the past few weeks you would likely have seen images surface on news sites and social media showing carcasses of thousands of fish floating in green scum. Desperate farmers scooping up lifeless hundred-year-old Murray cod, pleading for politicians to pay attention. In some areas, there’s no water at all. Just a bone-dry channel where the life-sustaining waterway ought to flow.

Lauren and Matt were recently forced to buy a large quantity of filtered river water from nearby Menindee. That area has also been affected, and though it’s been treated there are no guarantees of its quality. Desperate, Lauren and Matt are using it to bathe and wash their clothes, but they’re not prepared to take the same risk with Will. Their small rain water reserves are kept for him, and courtesy of a recent charity donation, she has also been using jugs of bottled water for his bath and for drinking.

“I have all the usual stresses of a first time mum, but then with the added element of where we’ll get clean water for him to drink, to bathe in, to cook his food, to wash his clothes,” she said.

"It's third-world conditions in Australia. Who would ever think that this could happen?"

So what's going on? What's caused this desperate situation? And what happens next for locals like Lauren and Matt?

What's happening to the Darling River?

The Darling River stretches over 1400km throughout far western New South Wales, from Bourke in the north to where it feeds into the Murray near the Victorian border. Though the whole river is struggling, the lower section is in crisis. No water has been flowing since August 2018, leaving some sections completely dry and others to pool with stagnant water.

This, combined with temperatures soaring over 40C, has encouraged blooms of blue-green algae to flourish in the remaining waterholes. As the Murray Darling Basin Authority warns, some species of this bacteria produce toxins, "that when ingested, can cause liver damage, stomach upsets and disorders of the nervous system in people. Direct contact with lots of blue-green algae can cause skin and eye irritations."

US studies have even linked a neurotoxin produced by blue-green algae, called BMAA, to a three-fold higher incidence of motor neurone disease.

Animals aren't immune either. Blue-green algae can also cause illness or death in livestock, and there is evidence it can poison wildlife and pets.

So far it's led to several mass fish kills, including that near Menindee earlier this month in which hundreds of thousands of cod, perch and herring died after the algae starved the water of oxygen.

How is the crisis affecting locals?

An algae 'red alert' is in place along large sections of the Darling, which warns residents not to use river water for drinking (without prior treatment), stock watering, or for recreation.

Like Lauren and Matt Blunden, farmers have been forced to rely on rainwater supplies, or purchase water to be trucked-in from elsewhere.

Lauren estimates her family has between four to six months worth of rainwater remaining, and though she and Matt have been on the station for seven years, they consider leaving almost daily now.

"We can't afford to be buying water to drink and bathe in all the time. So what's next? Do Will and I leave Matt here working and move into town?" she said.

"This could break our family. Matt comes home stressed all the time because of the threat to the stock, and I'm always stressed about our family... It's just breaking everything. It's hard to see any light at the end of the tunnel."

What caused the Darling River crisis?

Well, NSW Department of Primary Industries pinned the fish kill on weather: "It is likely linked to some rain and cooler temperatures in the Menindee area following an extended period of very hot weather," a spokesperson said in a statement to AAP.

As far as the broader issue, it's clear that excuse won't cut it.

According to Professor Fran Sheldon of the Griffith University Australian Rivers Institute, ecological evidence suggests that the Darling River should never naturally dry out in the way that it has - "even during drought conditions".

It is heartbreaking to watch the Bobcat drive along the front of the shacks at Sunset Strip on the Menindee lake to pick up the many roos that have died. I fill this up a couple of times a day and it is always empty in the morning. ???? They are so skinny #SaveOurDarling pic.twitter.com/7bwoK18tGR

— Molly Grace (@MollyGrace1) January 25, 2019

Instead, she - and many others - have pointed to man-made causes. Chiefly, water diversions in the upper regions of the river basin, where it's argued too many water licences have been handed out.

"This has essentially dried the wetlands and floodplains at the ends of the tributaries. Any water not diverted for irrigation is now absorbed by the continually parched upstream wetlands, leaving the lower reaches vulnerable when drought hits," Prof Sheldon explained via The Conversation.

"Unless we allow flows to resume, we’re in danger of seeing one of the worst environmental catastrophes in Australia."

What's being done?

Federal Water Minister David Littleproud has commissioned an independent scientific report into the fish kills in the Lower Darling, the final results of which will be handed down on March 31. Meanwhile, the NSW Government has appointed NSW Cross Border Commissioner, James McTavish, as Regional Town Water Supply Coordinator, to oversee water supply and quality in towns across the state.

“This could include the provision of funding for water carting to towns at risk of low water supply, or the provision of bottled or chilled water to schools or health care facilities in these communities,” Deputy Premier John Barilaro told The Guardian.

But many critics, including the Greens, have called for a Federal Royal Commission into the crisis.

“It’s time for the Government to take some real action to set this right. We need more environmental flows, an embargo on corporate cotton harvesting all the water it can, and a Royal Commission," Greens environment and water spokesperson Senator Sarah Hanson-Young said in a statement.

“Our river system is our nation’s food bowl and it is dying. The time to hide behind reports and hope it will all sort itself out is over. This environmental emergency must be remedied.”

Lauren Blunden supports the call for a Royal Commission, and urges Australian's to contact their local members to demand the issue is investigated, addressed and measures put in place to ensure it doesn't happen again.

"The weight of this shouldn't be on our shoulders - the people's shoulders," she said. "It's their stuff-up, and they need to take responsibility for it."