In Texas, parents search flood debris for missing kids. Are Australians ready for our own sudden floods?

Harrowing stories are emerging in the wake of catastrophic and sudden flooding over the fourth of July weekend in Texas – where many people were camping, and children were at riverside summer camp.

More than 80 people are confirmed dead (28 of whom were children) and 12 people are still missing. Parents have described finding children’s bodies while picking through flood debris searching for their own missing kids.

In Texas, the floodwaters rose very rapidly and in the middle of the night. Authorities had issued flood warnings but many people were still caught off-guard.

Sudden floods can also happen in Australia, as seen recently in New South Wales around Taree and Lismore, in the wake of ex-Cyclone Alfred.

As climate change makes severe weather events more frequent, it’s worth asking: how ready is Australia for its next sudden flood? And what could help to encourage people to leave while there’s still time?

It’s hard to appreciate how suddenly floods happen

Decades of research shows disasters can emerge and change very quickly. Hazards at night are especially difficult, because much can change while people are sleeping.

Even when flood warnings are issued, authorities can struggle to convince people the problem will affect them.

People often base their risk assessments on what’s happened in the past. So, if they live in an area that has experienced minor flooding before, they may think the current flood will be similarly minor.

Research also shows people often wait for extra evidence to confirm the initial warnings from officials. They might look to see if people around them are preparing to leave, or look for cues from the environment such as a sudden burst of loud rain.

Unfortunately, waiting can mean you miss the opportunity to leave. A road may close, or services may be overwhelmed and evacuation may no longer be an option. Escape options can narrow incredibly quickly, especially when people are asleep.

What about early warning systems?

The Albanese government announced in 2023 it would spend A$236 million over a decade to establish a national flood warning network. This will involve buying and upgrading flood gauges across Australia and trying to repair what the government has called “patchwork flood gauge network”.

That’s important, and it’s also positive to see other research on ways we can use existing technology infrastructure such as mobile phone towers to get early warnings on rising floodwaters.

But technology is only one part of the bigger picture. As growing body of research shows, many people do not evacuate even when warned about floods or fire.

Communicating risk in a disaster

Authorities must find ways to communicate disaster risk in a way that people will respond to.

Research shows getting the message out through as many channels as possible is crucial. People need to hear about the warnings on TV and on radio and online through various platforms and via local groups as well as national authorities.

The evidence also suggests people are more likely to trust messages coming from others in their community.

So, emergency agencies should work through community “champions” to help spread the word about an impending flood threat. It could be the principal of a school, a trusted source in a non-English speaking community, local emergency services volunteers or the manager of a local neighbourhood centre.

Emergency and government agencies need to identify trusted sources in communities, and build connections with them, before the crisis arrives to ensure information is disseminated smoothly in an emergency.