Panthers coach Ivan Cleary was among thousands of residents forced to evacuate Penrith on Sunday as the Nepean River rose to record levels not seen in 60 years.
Parts of Penrith and other areas along the Nepean were ordered to evacuate on Sunday as NSW battles devastating floods after days of unabated rain.
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Flooding along the Hawkesbury and Nepean rivers comes after the Warragamba Dam spilled over, prompting some concern.
Scores of people have already been rescued from floodwaters, while prison inmates have been evacuated and more than 100 schools remain shut.
Among the thousands forced to evacuate from Penrith were Panthers coach Cleary, as well as club chairman Dave O’Neill and welfare and education officer Shane Elford.
According to the Sydney Morning Herald, Cleary has been living in a Ladbury Avenue property owned by son Nathan while his Northern Beaches home is under renovation.
Cleary left the house on Sunday afternoon after the NSW State Emergency Service issued an evacuation warning.
The Panthers' preparations for their grand final rematch with Melbourne Storm this weekend have been thrown into chaos, with the club’s training facilities expected to go underwater in the floods.
The club's high performance centre sits on the banks of Peach Tree Creek, which spills off the Nepean river.
The club is reportedly confident the facility won't flood, but they may have to base themselves at a different location this week.
NSW bracing for more floods and lasting damage
Residents of North Richmond and surrounding centres west of Sydney were also told to evacuate on Sunday as the Hawkesbury River flooded.
Others at Eastern Creek and Windsor were prompted to leave before 3am and 9am Monday respectively.
The Bureau of Meteorology's Justin Robinson said the Hawkesbury Nepean Valley would experience its worst flooding since 1961, with the spilling of a full Warragamba Dam prompting concern.
Warragamba was hit by more than 150mm of rain in the 24 hours to 9am on Sunday, and more than 250mm over the past four days.
The Nepean River at Penrith could rise as high as 10 metres, while the river at Richmond and Windsor could peak around 16m on Monday.
"It is one of the biggest floods we are likely to see for a very long time ... flood waters at Penrith are expected to then move downstream and impact those communities at North Richmond, Windsor, Sackville," Mr Robinson said.
NSW Premier Gladys Berejiklian said the Hawkesbury Nepean Valley flood could prompt an additional 4000 evacuations.
The federal government's natural disaster arrangements have been activated for 18 local government areas across NSW.
"We are envisaging a one-in-50-year event, yesterday we were hoping it would only be a one-in-20-year event," Ms Berejiklian told reporters.
She rejected suggestions more water should have been released from the dam sooner, saying the volume of rainfall made it a moot point.
"You would've had to reduce the dam capacity to 20, 25 per cent," she said.
Greens Leader Adam Bandt described the weather event as “tragic” and said it served as a grim look into a future of bigger fires and worse floods for the country.
“’Unprecedented’ fires one year, ‘once in a 50 year’ floods the next. This is not normal,” Mr Bandt said in a statement.
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