Evacuation orders for Sydney suburbs amid 'volatile' flood threat

Parts of Sydney have been ordered to evacuate due to the threat of flooding as a record-breaking, "volatile, dangerous and dynamic" weather event continues to lash NSW.

The heavy rain kept falling overnight and into Sunday morning as rivers across NSW and near Sydney overflowed or threatened to flood.

As the Hawkesbury River flooded, residents in Pitt Town Bottoms, Pitt Town North, Cornwallis, North Richmond, Grono's Point, Freemans Reach and Agnes Banks – northwest of Sydney – were told to evacuate early on Sunday.

Residents within Cornwallis and Freemans Reach should have already evacuated.

The areas that should have already evacuated include:

All properties within the area of Freemans Reach bounded by Putty Road Road (from Currency Creek to Kurmond Road), Kurmond Road (including Vollers Land and Martins Lane), Terrace Road, the Hawkesbury River, Wire Line, Spinks Road, Currency Creek, Boundary Road, Howes Creek up to where it meets Currency Creek near Sackville, and back down Currency Creek.

People have been advised to seek refuge with family or friends outside the flood area, but an evacuation centre has been established at North Richmond Community Centre on William Street.

Residents in the Agnes Banks area need to be evacuated by 12pm on Sunday, the NSW State Emergency Services (SES) said.

"By 11am, leave the high danger area and move to safety outside the flood affected area," the NSW SES said.

In a separate evacuation order, residents in the Hawkesbury River area that contains Yarramundi Lane, Crowleys Lane and Inalls Lane have been told to get out.

People should stay with friends or family outside the flood area. Alternatively an evacuation centre has been established at Richmond Club, East Market Street.

Warragamba Dam, Sydney's main water source, spilled over on Saturday afternoon, causing river levels to rise along the Nepean and Hawkesbury rivers.

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Premier Gladys Berejiklian said on Saturday afternoon she had been briefed on the dam situation "in relation to a potential for a one-in-five-year, one-in-10-year, or one-in-20-year event".

Flood warning for south west Sydney

On Saturday night, the SES has also issued an evacuation warning for Picton CBD, south of Sydney, due to potential flooding of Stonequarry Creek.

"As a result of rising flood waters people within the Picton CBD should prepare to evacuate," the SES said on its website.

"Residents should monitor the situation and be prepared to evacuate when instructed to do so."

In an update on Sunday morning, NSW SES Wollondilly Unit said the creek "went down" overnight and the warning was no longer current, but they would continue to monitor the situation.

Operations to extend beyond Easter

SES Deputy Commissioner Daniel Austin said the service was dealing with downed trees, power outages, clearing of debris and damage to houses.

"Whilst a couple of areas have seen some receding flood waters overnight and into this morning, that heavy rainfall returning to those locations today will likely lead to additional peaks on those river systems," Mr Austin told ABC TV on Sunday.

"We're planning well beyond Easter for our own operations... just because the rain may stop on Thursday, the rivers naturally don't go back to their normal state and then there's going to be an extended recovery period."

Moderate flooding also continues along the Colo River, with farmers near the river told to be on alert for flooding and be ready to move livestock.

SES receives thousands of calls

Mr Austin on Sunday said emergency crews made 750 call-outs overnight on Saturday, and had responded to more than 4500 calls for help since Thursday.

Meanwhile, a bodyboarder in his 60s went missing off the Coffs Harbour coast on Saturday afternoon and crews will resume the search on Sunday.

Two stranded bushwalkers were also rescued in the Blue Mountains on Saturday as they were returning from a camping trip at Katoomba.

Strong winds have also caused damage, with a small tornado ripping through Chester Hill High School in Sydney's west on Saturday.

Minister for Police and Emergency Services David Elliot urged people to heed warnings and advice and prepare to evacuate if necessary.

He said it was "unacceptable" SES crews were putting themselves at risk for people who did not follow advice.

"We can't control the weather but we can control our behaviour," Mr Elliot said on Saturday.

with AAP

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