World Water Day

Why should we care about water science? 

In short, we couldn’t live on our blue planet without it.  Water sustains our bodies, our livelihoods and our ecosystems, but there’s more to the story than meets the eye.  

As abundant as it seems, only 0.5 per cent of the water on Earth is fresh water we can safely use. 

Worldwide, we face a water crisis. In Australia, we face both droughts and flooding rain. Climate change only adds to the challenge of ensuring and maintaining access to this vital natural resource. 

For these reasons and more, we acknowledge World Water Day. 

What in the world is World Water Day? 

On 22 March each year, the United Nations observes World Water Day. The aim is to raise awareness and inspire action towards the sixth Sustainable Development Goal, which is focused on access to water for all.    

World Water Day has a theme each year, and these have ranged from Women and Water way back in 1995 to Water for Life in 2005. This year, the theme is glacier preservation. Here in Australia, such a theme might reasonably feel far removed, but we should care about water anyway! 

On the driest inhabited continent on Earth, rainfall is a highly variable and precious phenomenon. However, as readers across Queensland and northern New South Wales will know all too well from recent extreme weather events, more is not always better. 

Whether it’s raining or not, a whole lot of work goes into providing us with clean, safe water to drink.

Glass of drinking water. Source: KOBU Agency via Unsplash

So, what’s going on in the water near you? 

Australia’s fresh water comes from a combination of surface and groundwater sources. (Surface waters include rivers, dams and reservoirs; groundwater comes from places like the Great Artesian Basin.) Water from these sources is filtered, tested and treated before it makes its way to you.  

The work doesn’t stop once the water we use goes down the drain. The first stage of treating wastewater is filtering out debris, sludge and scum. Microorganisms are then added to help break down excess nutrients like nitrogen and phosphorous. (Even though these elements are essential to life, too much of them in the aquatic environment can cause problems.) Once nutrient levels have been addressed, wastewater is filtered again and disinfected. It’s generally then safe to return to the environment or to recycle as greywater. 

Beyond these traditional water treatments, there are newer, more advanced techniques under development and investigation. Here are just two—and herein lies the real water science! 

In recent times, a group of chemicals known as PFAS have been in the news (and are the subject of an ongoing parliamentary inquiry). These ‘forever chemicals’ are found in everything from non-stick frying pans to firefighting foam and even paper straws. From each of these sources and many more, these chemicals can be washed into our waterways. 

As their nickname suggests, these chemicals stick around, becoming potentially harmful contaminants. The chemical bonds holding these chemicals together are notoriously strong, and this makes them even harder to deal with.  

Researchers at the University of New South Wales including Dr Jun Sun and Professor Naresh Kumar are working on new ways to break these bonds down. In particular, they’re studying a process that uses tiny particles called nano zero-valent metals. With the help of a catalyst (something that stimulates a reaction), the researchers have developed a system that can break down common PFAS. The next step in the research process is to test it on a larger scale. 

Meanwhile, in Tasmania, researchers are working on removing contaminants from water in a very different way. Atop an existing stormwater pond, special platforms have been constructed to host an array of native plants. The large surface area of the root systems of these plants, hidden underwater, provides a home for many, many microbes. Like they do in sewage treatment plants, these microbes help remove excess nutrients and other contaminants. The process can reduce greenhouse gas emissions from treated wastewater, and, as a bonus, the plants get access to nutrients they need to grow. 

Kingston Park Floating Wetlands. Source: Atlan Stormwater 

With so much water science behind every glass, why not raise a toast to scientists this coming World Water Day. If you’re keen to wade deeper, look out for the World Lake Conference coming to Australia for the first time in July. Water science is everywhere! 

References 

20th World Lake Conference. (2025). Lakes as Sentinels for Integrated River Basin Management. Wlc20.org. https://www.wlc20.org/  

Australian Government Department of Agriculture, Water and the Environment. (2021). Australia State of the Environment. https://soe.dcceew.gov.au/inland-water/environment/water-quality  

CSIRO Research. (2025, January 30). Constructed Floating Wetlands (CFWs) to enhance wastewater and surface water treatment. CSIRO. https://www.csiro.au/en/research/natural-environment/water/constructed-floating-wetlands  

Edwards, C. (2023, August 28). Paper straws could be packed with PFAS, study finds. Inside Water. https://insidewater.com.au/paper-straws-could-be-packed-with-pfas-study-finds/  

Foskey, D. (2024, November 14). Kingston Park: Tasmania’s First Floating Treatment Wetlands. Atlan Stormwater Australia. https://atlanstormwater.com/au/kingston-park-tasmanias-first-floating-treatment-wetlands/  

Matson, L. (2024, June 24). New method to degrade PFAS “forever chemicals” found effective in the lab. UNSW Newsroom. https://www.unsw.edu.au/newsroom/news/2024/06/new-method-to-degrade-pfas-forever-chemicals-found-effective-in-the-lab  

Parliament of Australia. (2024). Select Committee on PFAS (per and polyfluoroalkyl substances). Parliament of Australia. https://www.aph.gov.au/Parliamentary_Business/Committees/Senate/PFAS_per_and_polyfluoroalkyl_substances/PFAS  

Sydney Water. (2022). Wastewater treatment. Sydney Water. https://www.sydneywater.com.au/education/wastewater-recycling/wastewater-treatment.html