The Creepy Hidden Dangers in Flood Waters 11/03/25

Published Mar 10, 2025, 6:00 PM

Footage of people swimming and playing in floodwaters from Cyclone Alfred is circulating on social media—but are these waters safe? Molecular bioscientist Mark Blaskovich joins us to discuss the hidden dangers of floodwaters.

For more, head to news.com.au

From the news room and news still come today.

Hey there, I'm Emily Waterson and I'm filling in for mister Bucklow today. By now, I'm sure you've seen the various devastating videos of people caught in the floodwaters and storm surges across in all the New South Wales and Southeast Queensland. We've been across at all here at news dot com. But something else we've seen is footage of people not so devastated as they make the most of weather leading up to Cyclone Alfred. Amongst clips of flooded roads and fallen trees, there's been surfing, driving, mudslide races, you name it, and Ozzie has done it. But in case you've missed it or have a normal social media feed unlike myself, here's a glimpse of what's going on. We've got some pool noodle, We've got this Cyclone Alfred is here.

We are live on Twitch right now.

We're going down to the beach and we are going to attempt to be gone for a swim.

Do not try this, but come watch us be stupids live on Twitch right now now. May play into the laid back stereotype of Australians. But sometimes she'll be right, isn't enough as there's some very dangerous and nasty going on here that we tend to forget. It's not a matter of if there's something in the water, but what Well today, I've got an expert on to talk about just that, and trust me, you'll be glad you listened. Mark Blaskovich is a director of Translation at the Institute for Molecular Bioscience at the University of Queensland and he joins me. Now, so Mark, there's been quite a few video circulating of people enduring the floods, fleeing from their homes, but there's also been footage of people who are willingly going out there for a swim, diving into waters and even enjoying themselves. Is it ever safe just within floodwaters, even if it.

Looks clean, Yeah, it's I mean, it's probably not a good idea. The chances are that things will be fine, but the floodwaters will have passed through a lot of areas that they can pick up bacteria and sometimes viruses and sometimes parasites which if they're able to get into your body, potentially could do nasty.

Things and like quite nasty as well. Right, this can be a pretty severe infection if you come into Yeah.

So there's a range of different things that can happen, and probably the most common one is because you know, the floods in urban areas, the sewage catchments are exceeding their ability to get rid of sewage, and so you're starting to get raw sewage mixed with the flood waters. They're coming out of rural areas to begin with, and so they're going over you know, fields where cows manure is sitting in. So in particular, bacteria called Ecoli starts contaminating the water and then gets too much higher levels than is normally present.

An E.

Coli, if you ingest it gets into your system, can cause gastro intestinal illnesses if you have cuts or open wounds on your body. That's the other big concern because bacteria that are in the water can then get into your body, which normally has you know, mechanisms to get the bacteria away from areas they're not meant to be, but having enough cut or an open sore allows the bacteria to get inside and potentially get the bloodstream where you can now get bacterial infection within your blood which could lead to sepsis and needed hostilization and intensive antibiotic therapy to get rid of it.

Again, Are there any other types?

The other type is a bacteria called staff aureus sometimes not all those golden staff or one of the resistant forms of it, and that leads to it gets into cuts in particular and causes infections within cuts on the skin, and so that's also something you obviously don't want to have.

Okay, So it sounds like it might be hard to avoid altogether if you're moving around these floodwaters. Are there any precautions or preparations you can take to lessen your chances of coming into contact with these infections and bacterias.

Yeah, So the most important one is if you're you know, if you do have an open cut or sore, make sure covered with a bandage and try keeping it away from water as much as possible. Probably the most important thing if you're walking in floodwater is make sure you have on good footwear because obviously stepping on sharp objects that are being disturbed by the flood's a great way to get a cut and in the floodwater, which immediately then lets anything nasty in the floodwater get into your body as well, So protect a footwear when it gets around starts to the end stages of the flood and if you're cleaning up and again wearing gloves when you're cleaning up just to protect yourself from getting cuts and sores long paths instead of shorts.

You know, good robust footwear.

If you start working with dark mud, then having a mask would be really good to prevent any dust from inhaling. Any dust that's being generated that could be contaminated with bacteria as well.

So dust is another element famously not something I would think of as being a big problem during floods. Is this important for people to be aware of?

Yeah, So there's potential for inhalation and respiratory infections that come from directly inhaling either aerosolized water. So for some reason there's splashes of water that get into the air, and the bacteria within that water can then get into your lung. Probably more likely would be as I say, if dried mud, the bacteria are still viable within the dried mud, and if you're broom scraping that up or sweeping that up, potentially the bacteria within the dust that you're then inhaling, could get into your lung.

After the break, we'll find out what can happen if you ingest floodwater and what that seafoam you find on beaches is really made of. Welcome back. I'm talking to Professor Mark Blaskovich, an expert in microbiology. Some of the videos I've seen people diving into the foam like matter on the beaches. Have you seen this? Yes, yes, what actually is in that foam? Because I've heard it's not as fun as it may look, and it does look quite fun.

Yeah, So so my understanding is that, I mean, it can be caused by a variety of things, but the most likely cause is from dead algae, and so big algal blooms that have happened off in the ocean get washed ashore and then just the organic matter from the dead algae makes kind of a gelatinous mess, which then the thing of the ocean turns into the bubbles. So it's not inherently toxic, but sometimes the micro augae that lead to the blooms do have TX components within, So again it's one of these things probably okay, generally safe, but there are occasions where it could be toxic, and particularly again if you inhale or ingest it, then it you know, obviously gets into your body more easily and could lead to some less and desirable outcomes, you know, probably more along the lines of gasprotestinal distress and issues as opposed to really serious illnesses. But you know, again, if you can avoid it, it's probably better to do that.

Yes, for a few bliss moments in the foam, it's probably not worth it, especially because rumor has it this foam is also part.

Sewage, well a hundred percent.

I mean, it shouldn't be the major cause of the foam, but it will be present in there as well. Then during floods and storms the levels rise a lot, potentially to which would be considered unsafe levels for general swimming, just because the chances are then of ingesting or getting someone in your body, or much higher just because there are more bacteria sitting around.

You talking about the bacteria sort of sticking around, do we know how long for or is it just that as long as there's flood debris, there's bacteria.

I would yes, tend towards that that assumption. You know, bacteria can survive for quite a long time. If the floodwater is gone, they can still survive in the soil for weeks at a time. As I mentioned earlier, there's some bacteria that actually grow and live in the soil, and so they will be there at varying levels all the time. But that the higher levels found within the sewage water. You know, as long as there is water around, there will be bacteria present within that water. Just that depends on the level of contamination.

And finally, I know you've covered a lot, but do you have any other tips on how people can protect and mitigate harm to themselves.

It really just comes down to common sense methods of you know, protecting your skin from coming in contact with the water, and particular protecting yourself as they say cuts and scrapes that provide access because your skin is a natural barrier for bacteria getting inside your body, and you have bacteria all over your skin all the time anyway, and it's just.

The increased concentrations, you.

Know, and and floodwaters have things other than bacteria and viruses that are potentially dangerous to your body because they're again, particularly within the urban environment, there's lots of chemicals that have from very from the roads and the environment that the water has been through, and those aren't particularly good for you either, So it's not the spectera.

You have to worry about other things as well.

Well. That was Professor Mark Blaskovic with a lot of great information I won't be forgetting anytime soon. We'll be back tomorrow with another episode of From the Newsroom. Thanks for listening, follow us, subscribe to From the Newsroom wherever you get your podcasts.