Katherine locals survey damage from major flooding as volunteer 'army' rallies to help

An "army of people" has turned out to help Katherine residents hardest hit by the weekend's major flooding, as the community rallies behind those whose homes were inundated and now face a weeks-long clean-up effort.

Katherine, about 300 kilometres south of Darwin, experienced its worst flooding in 28 years on Saturday, with water levels peaking at about 19.2 metres.

The water shut roads, schools and the town's hospital and inundated homes and businesses, leaving hundreds without power and sewerage.

Gwendoline Drive resident and business owner Dave Sherrie's properties were among those to suffer the most damage, with water reaching as high as 1.7 metres inside.

Mr Sherrie said he was not surprised when the river broke its banks and started spilling onto his land, but did not anticipate the full extent of what was to come.

"It was coming in further than I thought, and once it reached our back house I said 'oh that might get wet now' and turned the power off to that," he said.

"That was about when we got out of here, had a mate come and pick us up in a boat."

By Monday morning Mr Sherrie was back on Gwendoline Drive surveying the damage, after the water streamed through his home and nearby electronics repair shop.

"We took most of the important irreplaceable stuff upstairs and other people's equipment, because we've got a bit of that," he said.

He said the financial cost of the damage would be "significant, but it's not the end of the world."

"A friend of mine's looking after my boys and he's here as well helping, he's an electrician so he's helping to try and get the power back on.

Mr Sherrie said he had bought in the area knowing it was a flood zone and was not looking for financial support, but he hoped the government would look at mitigation strategies before the next deluge.

"We're not in town so we don't get considered as much; it's only a small street with not many people, so not worth any real works to help try and combat it in the future," he said.

"But when you go through something like this, you think it's only a matter of time before it happens again."

He said the support from fellow Katherine residents had been "incredible", and once he was back at work in coming weeks "hopefully we'll be starting to help everyone else".

Trent de With has been among those leading the recovery efforts in Katherine.

He said he was just one of "an army of people out there" helping to clean up and get the worst affected back on their feet.

"That's what Katherine is all about," he said.

But Mr de With said many people had missed out on stocking up on food before Katherine's only supermarket closed and questioned why residents had missed out on government food drops.

"We were at the stage where we were handing out cookies from our smoko drum because people hadn't had food," he said.

"It's all well and good to say 'get 72 hours worth of food together', but when Woollies closes before an emergency happens, what are you supposed to do?"

Katherine's Woolworths re-opened at about 2pm on Monday, roughly 73 hours after it closed due to concerns for staff safety.

Scramble to save items as floodwaters rose

Housemates Maggie Nicholls, Grace Kennedy, and Georgie Moss had floodwaters rise around their house on Lindsay Street on Saturday afternoon, inundating the ground floor.

"About midday we went for a walk and were feeling optimistic, [we thought] 'let's go check out the rest of the town', and we came back and had to walk through hip-deep water," Ms Moss said.

The water flooded their downstairs bedroom and laundry.

The house was surrounded by floodwater for hours and the power went out.

When the water started to recede around lunchtime on Sunday, the housemates were able to start the clean-up, hosing out the dirt downstairs and wiping down mouldy walls with vinegar.

They said they had also noticed an influx of small critters trying to escape the water.

"[There are] lots of huntsmen and lizards taking refuge on our walls," Ms Nicholls said.

The group said they were "thinking of surrounding communities" and others in Katherine who had suffered more serious inundation.

In Katherine's north, resident Deb Wildish said she was thankful to live in an elevated house after up to 40 centimetres of water flowed underneath her verandahs.

"I just started to lift up anything I didn't want to be damaged from downstairs, got the fridge up on milk crates," she said.

"I actually ended up moving my vehicle at 1 o'clock in the morning on Saturday because I just suddenly realised 'I actually think this is going to be worse than we're predicting'."

Ms Wildish said she felt "blessed" to have only lost a dishwasher to the floodwaters, while others in lower houses had been much harder hit.

"I'm just having to really clean up a lot of stuff that ended up getting floodwater and mud through it," she said.

"Our power was out for around 27 hours, but everything stayed frozen in my freezer, so feeling incredibly lucky and much luckier than a lot of other people."

The Parks and Wildlife community engagement ranger noted she had seen other residents "wading through waist-deep floodwater" and urged people to remain croc-wise, while also taking precautions to avoid exposure to the soil-borne infection melioidosis.

"Do not go through floodwater, do not go within 5 metres of the edge of the river," she said.