Nadia Zarb can already see, and smell, the mould in her art gallery in Taree. The building on Victoria Street was inundated during flooding that hit the Hunter and mid-north coast ofNew South Walesat the end of May.
Water filled the storage space below ground, the art supply store on the ground floor, and the loft exhibition space, reaching to just below Zarb’s home on the top level.
Water and mud still lies thick on the lower levels while her property is now filled with spores.
Mould is forming on her art supplies, Zarb says, texting through pictures of wooden art models covered in black and grey mould. It’s also in the walls, and areas she can’t access.
“While it’s cold and damp, it’s really difficult to dry things and then you start to get that damp smell and that musty, mouldy odour,” she says.
Experts are warning about the “huge problem” of mould in homes and businesses affected by the recent floods. Because they happened in winter, it will be “almost impossible” for many homeowners to dry out their properties and eradicate the dangerous spores, they say.
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“This flood is badly timed for mould. That’s going to be a huge problem,” says Ian Wright, associate professor in environmental science at Western Sydney University.
“Because it’s so cool now … and because you’re down low in the landscape, so the dew point [is low], it’s going to be almost impossible to get rid of that moisture. If this flood had happened a couple months ago in early autumn, there [would have been] much better prospects of drying out.
“But mould absorption into timber, particularly, or chipboard or plasterboard – almost everyone is going to have problems with mould.
“It will make some places unsafe to live in. It makes me feel sick to think about it, actually.”
Lab researchpublished in the CSIRO journal Microbiology Australia in 2023 found there was an increased risk of fungi and mould after flood events,because ofconditions such as high humidity, and “an extra nutritional load comprising of debris, vegetation, dead animals, wet surface soils and other displaced materials”.
The research found that the mould could colonise surfaces and “penetrate deep into buildings”, leading to “a host of well documented associated health risks”, including respiratory infections and poisoning from mycotoxins, particularly in “already stressed or immunocompromised individuals, who may be suffering from displacement and psychological distress”.
Elly Bird, the executive director of Resilient Lismore, said mould was a huge concern after the 2022 floods in the Northern Rivers region.
“After our flood, we had constant rain for three or four months, so managing mould was really a significant issue for our communities, and people were having to really stay on top of constantly cleaning and monitoring and preventing,” she said.
“I think it’s important to not understate the risk that can come from mould and the impact that it has on people’s health.
“It’s really important to be vigilant and to make sure that you’re drying out flood-affected properties as best you can, and treating mould as you find it, so that you can prevent further issues down the track.”
Wright and Bird recommended people use fans and heaters to dry out their properties completely, and also urged people to consider rebuilding with non-porous building materials less likely to retain water and to become a breeding ground for mould.
“There’s some really good guidelines that the New South Wales Reconstruction Authority have around flood resilience design that do things like: creating ways for water to move out of the property quickly, thinking about the types of cabinetry that you put back into homes, trying to avoid just using chipboard or gyprock, if at all possible, and using solid doors rather than hollow core doors,” said Bird. “There’s lots of tips and tricks that you can do to prevent more significant impact next time. And now is the time to start to be really carefully thinking about that.”
Most of the construction of Zarb’s 1950s building is hardwood and plasterboard – both of which retain water. After the 2021 flood, she replaced some of the lower boards in her walls with water-resistant weatherboard, and now is ripping out the rest of the walls to replace them this time around.
Power is not yet fully reconnected at her property, meaning she can’t use fans or heaters to help dry her basement floor, which is still waterlogged and full of mud.
“I’m just airing it out at the moment, and you know, some spots you can’t really get air to, so that’s where the mould started.”