When and where the Murray River floods are expected to peak in Riverland, South Australia

As water levels rise along the Murray River in South Australia, residents, businesses and authorities are keeping a close eye on what is to come.

Many houses have already been flooded with water and others are without electricity.

Here’s a look at what to expect in the coming weeks.

What is the prediction now?

The South Australian government predicts that between 190 and 220 gigalitres of water will flow down the river a day when the flood peaks in late December.

Initially, authorities expected there would be two peaks, one in mid-December and another later in the month, but now they believe there will be a single peak, with high water levels for months.

The cause of all this water is the enormous amount of rain that has fallen in NSW, Victoria and Queensland over the last three years.

Australia is in the third consecutive year of La Niña.

La Niña is a meteorological phenomenon determined by changes in the winds and the water temperature in the tropical waters of the Pacific Ocean that brings with it a greater probability of precipitation.

With the basins already swollen, this year’s rain has caused widespread flooding in the Murray and Darling river systems with much of that water now ending up in South Australia.

How can we know where it will flood?

Flood modeling maps they are providing key guidance for authorities and residents alike.

Created by the Department of Environment and Water, they are designed to give everyone in the region the opportunity to see what the different flows could mean for their cities and properties.

Authorities caution that these flood maps should only be used as a guide.

They were created in 2014 and have not been adjusted for any of the new levees created in recent weeks.

What exactly do the maps reveal?

The maps show what a flood will do to the river when the flows reach a certain level.

It shows which roads will be cut, which towns will be most affected, and which houses and properties could be flooded.

Renmark, with a population of 7,500, will be the first city to receive the full flow, four days after the waters peaked at the South Australia border with New South Wales and Victoria.

Renmark resident Peter Smith, who survived the Riverland floods of 1956, has reinforced levees built next to his home to protect him, his neighbors and the local hospital.

“All the work has to be done before it gets here, so everybody’s hoping that what they’ve done is good, and I think it is,” Smith said.

Mr Smith’s home is next door to the Renmark Paringa district hospital and care center for the elderly, which has evacuated more than 50 patients as a precaution.

Around 30 of those residents have been transferred to upper sections of the hospital, while 20 have been taken to alternative centers.

As we follow the river, next in line are the other large towns of Berri, which has a population of about 4,100, and Loxton, home to 4,500 people and which will see peak flows two to three days after Renmark.

These towns, like most of Riverland, largely serve as service centers for local primary growers, who rely on irrigation from the river to grow wine grapes, stone fruit, and almonds.

It is some of these primary producers in low houses who will be inundated.

Many properties have already gone under.

Shacks are also expected to be affected and roads cut, but mapping shows that the main centers should emerge largely unscathed.

How does this flood compare historically?

While river heights are already surpassing 1974 historical levels, the 2022 flood is expected to be much less than the disastrous floods of 1956.

In that flood, the flows reached 341 gigalitres per day.

The main streets of Renmark and Mannum were submerged in that devastating event.

Dave Schache recalls that sandbags were placed on main streets to protect as many businesses as possible.

“The sandbags were 10 feet high on the side of the road and the water was running under our feet,” Schache said.

In the 2022 flood, vacation homes built from 1956 and just above river level are expected to be the most affected.

1,100 houses have already been affected, but that number is expected to rise to around 4,000.

How will the Murraylands fare?

Many properties from Cadell a Morgan to Blanchetown and Swan Reach are already partially flooded.

The water level is already close to the first floor of many properties, and is expected to rise much higher, with the peak reaching 10-12 days after passing through Renmark.

Next in line is Walkers Flat, with the model showing many houses will be flooded.

Further south is Mannum, which has a population of 2,400.

Businesses and houses on the wrong side of a new levee appear to be at risk, as do holiday homes on the opposite side of the river in the Bolto Reserve.

The authorities, as they did in 1956, have built a dike on Mannum’s main street to protect most businesses.

Whereas in 1956 they predominantly used sandbags, this time they have used new DefenCell dams.

Mid Murray Council chief executive Ben Scales said while the flooding was moving very slowly, the river was clearly rising, along with people’s anxiety levels.

‘It’s not a flash flood. It’s been coming for a while. But we don’t really know what’s going to happen, so it’s creating some anxiety among residents and the community at large,” Scales said.

While riverfront properties like the Murray Bridge Club appear vulnerable, the town itself should be safe as the waters peak about two weeks after passing Renmark.

What help is offered to those affected?

For those who need help, the South Australian Government is providing emergency housing to eligible Riverland residents.

Emergency Personal Hardship Grants worth $1,000 are available to families.

Grants are also available, in certain circumstances, for people who need generators due to power outages.

More information is available at sa.gov.au/floods or by calling 1800 362 361.