Much of the city of Townsville in Queensland state is flooded, with residents left without power and some compelled to seek safety on the roofs of their homes, according to CNN affiliate 7 News.
Intense rain on Sunday forced authorities to open the floodgates on the Ross River Dam to relieve pressure, releasing around 1,900 cubic meters of water per second downriver.
"Dangerous and high-velocity flows will occur in the Ross River Sunday night into Monday. Unprecedented areas of flooding will occur in Townsville. Expect access routes to be cut," the Queensland Bureau of Meteorology said in a statement.
On Saturday, as the flooding rapidly worsened, police in parts of Queensland were going door-to-door to warn residents to leave their homes.
"It's basically not just a one in 20-year event, it's a one in 100-year event," state Premier Annastacia Palaszczuk said Saturday, according to CNN affiliate 9 News.
Speaking Monday, Palaszczuk warned: "There's going to be heavy rainfall over the next couple of days."
"There will also be damaging wind gusts and intense rainfall with significant flash flooding. So, once again, our message is, if you don't need to be out on the roads, please don't," she added.
Hundreds of homes in Townsville have already been inundated, 7 News reported, and there are fears between 10,000 and 20,000 properties could be at risk from the coming bad weather.
To make matters worse for the terrified residents fleeing their homes, there have been numerous sightings of crocodiles and snakes being swept along with the floodwaters, 9 News reported.
Mundingburra resident Erin Hahn told the broadcaster she spotted a freshwater crocodile in front of her father's house Sunday night.
"(It) was nearly a meter or two long (3.3 to 6.6 feet)," she said.
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