Evacuation orders have been issued for parts of North Richmond, while North Richmond and Yarramundi Bridges are now closed, and Windsor Bridge could close tonight.
NSW SES Hawkesbury Unit's Facebook page stated that parts of North Richmond had been asked to evacuate, as follows:
"There is a likely chance that the Redbank Dam will fail and cause flooding to properties below the dam. NSW SES is directing people within North Richmond to evacuate the high danger area:
"Where to go: Stay with family or friends outside the impacted area
"Simple things you can do now:
The Bureau of Meteorology said the Hawkesbury River at North Richmond was likely to exceed the moderate flood level (7.90 metres) around 5pm Wednesday. The river level may exceed the major flood level (10.50 metres) Wednesday evening and may reach around 14 metres during Thursday, with major flooding. Further rises are possible.
Over in Windsor, some people were gathered at Windsor Bridge to view the rising Hawkesbury River water levels this afternoon.
Kevin Jones, NSW SES Hawkesbury Unit Commander said Windsor Bridge would likely close "in the next few hours"
"We'll be doing some evacuation warnings in the low lying areas shortly," he said.
These coulod include the Richmond lowlands, Agnes Banks, parts of low lying Pitt Town and Pitt Town Bottoms and North Pitt Town near the river, Grono Point, and some areas of Lower Portland, Mr Jones said.
He said impacted households should receive a text message, and if possible, SES or RFS would knock on their door. He encouraged people to keep an eye on the Hawkesbury SES page on Facebook for local updates.
"Please don't drive in flood water. And if anyone needs assistance, we're trying our hardest to get to them," Mr Jones said.
"There's not a lot of resourcing for SES because there's so much happening up and down the coast.
"We have teams and they're slowly getting to it.
"If people need help then ring SES on 132 500 or if its life threatening then call triple-0."
The Bureau of Meteorology has warned that the Hawkesbury River at Windsor is expected to exceed the moderate flood level (7 metres) Wednesday evening. The river level is likely to exceed the major flood level (12.20 metres) and may reach around 12.50 metres, with major flooding during Thursday. Further rises are possible.
The last time Windsor Bridge flooded was almost a year ago, at the end of March 2021, when the height reached 12.5 metres.
For updates during the night and through the early morning, please go to the NSW SES website at https://www.ses.nsw.gov.au/
Local information is also being shared on the NSW SES Hawkesbury Unit page on Facebook at https://www.facebook.com/seshawkesbury
For road closures, visit Live Traffic NSW at https://www.livetraffic.com/