Australia Weather News

Parts of Bolong Road at Bomaderry were submerged. - ABC

Residents on the New South Wales South Coast are assessing the damage to their properties after the region experienced its worst flooding in almost 30 years.

Almost 400 millimetres of rain drenched suburbs in the Shoalhaven over four days.

The Shoalhaven River rose to 4.13 metres, causing its swollen creeks and tributaries to spill, inundating dozens of local roads and neighbouring properties.

"It's been quite an amazing event and the area has been hit extremely hard," Shoalhaven Water acting director Robert Horner said.

"Our water supply dams in the Shoalhaven are overflowing, and our main supply dam, Tallowa Dam, peaked at 3.3 metres over the spillway.

"That equates to approximately 20 years of water usage in the Shoalhaven that has overflowed from Tallowa Dam in 24 hours."

Dozens of flood rescues

There was also minor flooding around St Georges Basin and at Sussex Inlet.

The State Emergence Service received 473 calls during the storm event for help with sandbagging and fallen tress.

Spokesperson Dave Rankine said local crews also performed 28 flood rescues.

"Particularly in the Nowra region, we did experience a number of people who decided to try crossing flooded roads and causeways in their vehicles," he said.

"We are expecting further weather — this won't be the last storm — so people need to seriously consider their safety.

"These rescues put the life of the driver, their passengers and our SES volunteers at risk."

Endeavour Energy said more than 13,500 homes and businesses were without power at the height of the storm.

The wild weather also caused more than 270 electrical hazards across the network.

Farms inundated

Primary producers across the region have been among the worst affected.

Greenwell Point oyster farmer Sally McLean said she had to shut her business after some of her oyster leases in the Shoalhaven River were flushed with fresh water.

She said the extent of the contamination was unclear.

"We will be unable to harvest any oysters for probably at least another two or three weeks," she said.

"What we're worried about is our Pacific oysters, as we've had a lot of water come down that river.

"The Sydney rock [oysters] just need a lick of salt, but the Pacific need a little bit more salt to survive, so we'll go out there probably in a week's time to see if they're safe."

Jaspers Brush dairy farmer Justin Walsh said he experienced the worst flooding he had seen on his property in 36 years.

"This is probably the biggest flood we've ever had in terms of where the water has come up to on our property," he said.

"In terms of the infrastructure, a lot of fences and things are under water.

"We won't really know the damage until the water recedes."