The small community of Wee Waa in northern New South Wales has become its own island, after being isolated from flooding overnight.
The community has been isolated by road from all directions since yesterday evening after the Namoi River reached a height of 7.07 metres, 37 centimetres above the predicted river height.
It may be cut off for more than 10 days.
New South Wales SES' Dave Rankin said the town was protected by a substantial levee, but isolation would place pressure on the community with freight unable to reach the community via road.
"We'll be keeping a very close eye [on the community] and managing any resupply issues that arise by boat or by using helicopters," he said.
"We've done a lot of work there to make sure people were aware of what's going on in the Wee Waa community and stock up."
Mr Rankin said they were prepared for any medical emergencies that may also arise.
"If there's a medical emergency and the hospital isn't able to deal with it, we have helicopters on stand-by in Narrabri to transport patients out of town."
Supermarket kept busy
Wee Waa supermarket manager Natasha Suckling said the store had been busy in the lead up to the road closures.
"We've been extremely busy, customers trying to come in and get their groceries before they get cut off from Wee Waa," she said.
"We are pretty low [in groceries] at the moment and hoping to get a truck in today: We have run out of bread and long-life milk to resupply the shelves."
Ms Sucking said locals were stocking up on non-perishables to keep them going.
"People are buying tinned food, noodles ? stuff that they can store in the cupboard.
"We have had four checkouts going yesterday and customers lining up, we've definitely been busy and have put extra staff in to help out."
'Floodwaters better than dust' for crops
Some producers have seen the gamble of harvesting last week pay off on their paddocks, now underwater.
"There was a night shift on one of the river paddocks that my brother was doing, and he was dodging mud-holes, getting as much off as we could," mixed cropping farmer Sam Kahl said.
"I jumped on the header and thought I could get more off, but I was wrong. We did as much as we could."
The Kahl family property grows cereal and feed crops, and has the majority of its grains left to harvest protected by levy banks.
"Our bread and durum wheats will be affected by this rain. It should be right, it'll still be there. I don't know what the quality will be, but it will still be there," Mr Kahl said.
Before floodwaters completely isolated the area, an influx of GrainCorp trucks were on the roads, moving grain elsewhere.
Summer crops such as cotton have just been sown across the North West area from Gunnedah to Moree, which were now underwater in some parts.
Nevertheless, farmers like Sam Kahl were optimistic for its survival.
"Floodwaters are better than a dust storm," he said.
"It's sitting there happily. But if the floodwaters stay up, we may need to bring sprayers in for the weeds."
Some crops could be lost
Robert Eveleigh is the chairman of the Lower Namoi Cotton Growers Association.
He said any more rises could see a significant area of crops lost that do not have the protection of levees.
"Most of the irrigated [crops] in the Lower Namoi are well protected with levees," he said.
"Outside those levees there are crops that are in jeopardy and some of those have gone underwater at present levels.
"There's been a lot of cereal crop yet to be harvested and some of those are on the floodplain and have water on them now."
© ABC 2021
13:12 AEDT Goondiwindi's 65-year-old levee has once again saved homes from major flooding, but the town is now surrounded by water and there are fears some rural communities could cut off for days, if not weeks.