CALE: This isn't a river.
It's the town of Lismore in northern New South Wales.
Last week, it was hit by the region's worst flood on record.
People died and hundreds of homes were submerged
as boats became the only way around town.
It was crazy.
You know, some people couldn't even leave their house.
Like, my school has been, like, filled all the way to the top.
It's really sad.
GIRL: My dad works at the evac centre in Lismore
and he has to handle how everything works
and all the donations
and all the lovely things everyone brings in,
and he just gets very stressed from that,
so that's affected my family as well.
GIRL: Right now, I'm living at a friend's house with my family,
and another family's staying there as well.
But our house that was in the floods,
it's pretty wrecked, it's really muddy.
Um, we've started cleaning it out, but it still has a long way to go.
It's been a similar story across much of Australia's east coast.
If you fall asleep, you could wake up with water in your room,
so it's a bit scary.
Seeing a flood for the first time is kind of crazy,
and especially when your whole school's underwater.
It's mad.
The rain began a couple of weeks ago,
filling up rivers and dams until they overflowed.
Brisbane and the Gold Coast were the first to flood.
Then the rain made its way down to Sydney,
inundating towns in between.
My school was closed because all of the water was in...
It was like a big river in the middle.
Well, our driveway has been flooded
and it was that deep that we could go boat racing.
People prepared for the floods as best they could, using sandbags,
which can help to keep out water and mud,
and even temporary levees like this one in Maryborough,
which saved the main street from flooding.
Hundreds of thousands of people
were told to leave their homes throughout New South Wales,
but for some, the water rose too quickly.
SES and other volunteers rescued hundreds of people, and even pets.
We've lost everything. I just had to rescue the goat.
I've got a surf lifesaving background
and I was like, "OK, I've got to get out here and help."
This lad needed a bit of help, so, you know, towed him out,
and then I'm going to keep doing the same thing
for, hopefully, the rest of the day.
So, what's going on?
Well, the Bureau of Meteorology says
it's because we've had two big La Nina events in a row.
La Nina is a weather pattern that brings more wet weather
to the east coast of Australia,
and last year, it filled up catchments,
which meant dams and rivers were already full
when this huge batch of rain arrived,
and it was huge.
In fact, Brisbane received more than half
of its average annual rainfall in just a week.
Scientists say that these sort of events
are becoming much harder to predict because of climate change,
so it can be really hard to evacuate people in time.
While wet weather is continuing to cause problems, in some places,
floodwaters are slowly going down,
revealing all the damage that's been done,
and these towns say they're going to need a lot more help to clean up.
It's going to take a long time
for us to even get back the slightest bit of normality.
GIRL: Just jumped at whatever opportunity
to help each other, help clean our houses.
And my school's community, they've just donated so many things,
and they've cooked meals for everyone,
and it's really sweet.
But everybody is snapping into action
and helping each other, and we're just all working together
to try and get our community to thrive again.
Some things can't be replaced, but people are working together
and supporting each other as the clean-up begins.