It comes as some of the small town’s residents were issued an evacuation order on Tuesday morning as water began flowing in the town’s main street.

Ungarie is the worst hit area in the region, but with more rain forecast later in the week, the State Emergency Service will remain on alert across the Riverina.

Ungarie farmer David Patton, whose family has been working the land he’s on since 1923, said the event was a part of life on the land.

“We get the flooding about 24 hours before Ungarie gets it,” Mr Patton said.

“It comes up quick, but it also goes down quick.

“We usually get a flood event around every 10 years.”

But the small town has been hit by floods three times in the past six years.

“Our house is up on the hill, so it’s not too bad,” Mr Patton said.

“There’s more money in mud than there is in dust.”

The biggest concern for the 50-year-old is that  his sister-in-law is due to give birth.

“We might have to get the tractor out to get to the hospital,” the Ungarie flood committee member said.

Mr Patton’s wife, Emily, posted pictures on Facebook of the farmer mustering sheep in the floodwaters.

SES Murrumbidgee region deputy controller Jon Gregory said there were still many roads affected by flooding.

“I need to stress again that people do not drive through floods,” Mr Gregory said.

SES crews will remain on tenterhooks as forecasts point to more rain later in the week.

“We’re looking at getting 30mm in the eastern parts of the region,” Mr Gregory said, adding that it wouldn’t take much rainfall to tip swollen water systems over the edge. 

The Humbug creek rose half a metre in the space of four hours at the town’s bridge, going from 1.1m at 2am to 1.6m when the sun rose, residents say.

It is understood the waters have reached the main street and some low-lying homes and businesses.

The evacuation order affects low-lying homes in Euglo Street and homes and businesses in Woolongough Street, the main street of Ungarie.

“Do not delay your evacuation,” Nichole Richardson, the SES’s Lachlan Region incident commander, said in the order.

“You could become trapped and need rescue. Remaining in flooded areas is dangerous and may place your life at risk.

“Wherever possible, people should go and stay with family or friends, or make other accommodation arrangements. For people who need assistance, emergency services are in town and providing assistance.”

The evacuation warning was issued around 1pm on Tuesday, telling residents in 13 streets they should get ready to go in case an order is made.

The warning covers Robert, Muriel, Caroon, Mackrell, Lynda, Ungarie, Alkaville, Euglo, Merringreen, Herbert and Short streets and Kikoira and Yalgogrin roads.

Roads have been closed around Ungarie and beyond in the Bland Shire as Humbug Creek reached 1.6m at 6am on Tuesday morning.

A handful of homes and businesses have been affected by the floodwaters so far, but the waters are slowly rising in what is a complicated flood system, an SES spokesman said on Tuesday morning.

“A couple of residents have already left of their own volition and are staying with family or friends,” the service’s Phil Campbell said.

“We’ve had SES and VRA (Volunteer Rescue Association) volunteers out there helping over the last couple of days, lifting furniture and sandbagging.

“(The creek at ) the bridge to Ungarie Central School is about 1.4m today, so the kids had a flood day. It is still rising, and slowly encroaching on the main street.”

The nature of the creek system and the low, flat area means the waters move differently to areas such as Wagga, where floodwaters can be more easily predicted and measures upstream, Mr Campbell said.

Estimates on where the water will reach depends heavily on local knowledge and working on flood history.

“It’s a really complicated flood system with lots of little creeks and floodwashes,” Mr Campbell said.

“It’s a much more complicated, difficult place to work with and there are no flood gauges on Humbug Creek. We really rely on locals and prior knowledge.”

SES crews have joined the local Rural Fire Service teams and are being supported by Bland Shire Council staff.

An SES crew was brought in from Cowra on Monday to assist with sandbagging and to monitor the situation.

Ungarie Central School students were sent home on Monday morning and won’t be heading back to class today, with floodwaters apparently reaching the grounds.

The school posted several photos on its Facebook page on Tuesday morning, updating parents and students that it would be another day of no lessons.

“The situation remains the same this morning,” the school commented on a prior post from relieving principal Terrie Payne, updating parents on the situation.

“Ungarie Central School is non-operational. There will be no staff or students on site today.”

The Central West Slopes and Plains should expect more rain on Tuesday night, the Bureau of Meteorology stated, and sheep graziers in that region as well as the South West Slopes have been issued a cold weather warning.

Local roads have been closed across Bland and Temora shires, both of which were struck by heavy rain and swollen creeks on Monday.

Further afield, Beckom’s main street was also underwater on Monday afternoon.

SES Murrumbidgee region deputy controller Jon Gregory said the Mirrool Creek began to drop about 4.30pm on Monday, but warned there was still plenty of water over roads.

The engorged creek meanders around Ardlethan, Mirrool and Beckom.

Temora’s Lake Centenary spilled on Monday, causing a vast amount of water to cross Goldfields Way.

Pre-emptive sandbagging was carried out around the Mirrool Creek at Beckom, SES Murrumbidgee region deputy controller Jon Gregory said.

There were more than 20 call outs across the region on Monday, including two potential rescues from floodwater.

In one case, at Tallimba, a motorist self-rescued after attempting to drive into floodwater.

Despite reports of a flood rescue required at Rankins Springs, a five-hour search yielded nothing.

"Most of the people that get caught up in floods are local residents who think they know the conditions," Mr Gregory said.

Motorists across the Riverina have been warned to use common sense this week and not just rely on road closures to warn them of danger.

“With flooding events in and around the area councils may be inundated with jobs and may not be able to close roads immediately,” Chief Inspector John Wadsworth from the Griffith Local Area Command said.

“Motorists must be responsible for their own safety and if they see flood water they should stay safe and not try to drive through it.

“We’ve seen the tragedies in northern NSW recently where people took a punt and drove through flood waters and lost their lives.”

Last Friday, researchers at the University of New South Wales demonstrated cars could be swept away easier than people in flooded water.

Principal engineer Grantley Smith, who led the research, said he was surprised at “just how little water it took to make even a large vehicle unstable”.

“They became vulnerable to moving floodwaters once the depth reached the floor of the vehicle," Mr Smith said. "Even in low water depths and slow flow speeds, floodwaters had a powerful enough force to make them float away.”

In world-first tests using actual cars instead of miniature models, the researchers found a small car like a Toyota Yaris – which weighs 1.05 tonnes – was moved by water just 15 centimetres deep that had a flow speed of 3.6 km/h. It was carried away in 60 centimetres of water.

A larger Nissan Patrol four-wheel drive, at 2.5 tonnes, was moved by 45 centimetres of water and began floating in 95 centimetres of water, able to be pushed along by just a finger.

The cars were moved so easily partly because even shallow water can be deceptively strong, and partly because modern cars are so air-tight that instead of taking on water they get pushed along by it.

“People don't realise that even slow-moving water packs a powerful punch," Mr Smith said.  "Water is heavy: each cubic metre weighs about 1000 kilograms.”