What is recycled water?
Recycled water is wastewater that’s treated to a safe standard so it can be re-used for other purposes.
Our recycled water program has benefits including:
- Protecting natural water sources from overuse.
- Providing a valuable water supply alternative for non-drinking uses.
- Reducing the amount of groundwater needed for irrigation.
- Reducing the amount of treated wastewater discharged to waterways.
- Helping reduce the use of fertilisers due to the nutrients in the recycled water.
We recycle around 15 to 20 per cent of all the sewage we treat each year across our region. Our region’s reliable rainfall and access to groundwater means there are limited markets for the recycled water.
Where is it used?
Most recycled water is irrigated on farms near 12 of our inland sewage treatment plants. We also have agreements with several farmers to supply recycled water for agricultural irrigation.
Across our region, recycled water is used on several golf courses, sporting ovals and racecourses.
The Mortlake Power Station uses recycled water to cool turbines over summer. This eases the demand on other local water resources.
Specialist management and regular monitoring are needed when using recycled water for irrigation. This ensures its safe and sustainable use, meeting Environmental Protection Authority (EPA) requirements.
What about the ocean outfall sewage treatment plants?
Wastewater produced at our ocean outfall sewage treatment plants in Warrnambool, Port Fairy and Portland has a high salt content. It’s discharged to the ocean under EPA licensing requirements.
Expensive and energy-intensive treatment would be required to make this water suitable for any industrial, agricultural or recreational uses. However, we’re investigating options at Warrnambool and we hope this might identify new opportunities for our other ocean outfall plants.
Emerging contaminants in recycled water
Emerging contaminants are known as ‘emerging’ because there is limited information about them or the long-term risks they may pose to our health and the environment.
Emerging contaminants are natural or manufactured compounds that may cause known or suspected harm to our environment and/or human health. They include:
- Pharmaceuticals
- Pesticides
- Industrial chemicals
- Herbicides
- Personal care products
- Endocrine disrupting compounds.
An example is per- and polyfluoroalkyl substances (PFAS) which have become more widely recognised in recent years. Known as ‘forever chemicals’, PFAS are now regulated because they don’t easily break down and can stay in the environment and humans for a long time. They’ve been around since the mid-1900s in products that resist heat, stains, grease and water.
They’re commonly found in household products including some non-stick pans, sunscreen, raincoats and make up. In the past, they were often used in firefighting foam and waterproof sprays. As a result, there are low levels of PFAS in soil, sediment, water, and animals across most of Australia.
Contaminants can enter the environment through urban and agricultural runoff, direct use on land, and when products are disposed of in waste systems – through, sinks, showers, toilets and trade waste.
It’s important to note that the presence of emerging contaminants does not necessarily mean there is a risk to human health or the environment. The risk depends on the compound, concentration, and exposure route and duration.
While our sewage treatment plants were not originally designed to manage emerging contaminants, our treatment processes may reduce, remove or destroy many of these compounds. While some may still remain in treated water, we’re continuing to learn more and improve how we manage them, with a strong focus on protecting our community and the environment.
The Class B and C recycled water we produce can be used for livestock grazing and fodder, and the irrigation of public spaces such as sporting ovals or golf courses. While some emerging contaminants may still be present in Class B and C recycled water, this water is managed in accordance with strict requirements for its intended use. These requirements include measures such as water quality sampling, operator training, irrigation scheduling, land capability assessments, and monitoring of soil and plant health.
We regularly audit customer compliance with these controls to ensure ongoing safe and sustainable reuse of this valuable resource.
We’re supporting and partnering with regulators, researchers and other water utilities to better understand the presence and potential risks posed by emerging contaminants in the environment.
Further information about emerging contaminants can also be found on these websites:
EPA Victoria – Emerging Contaminants in Recycled Water
EPA Victoria – Emerging contaminants in wastewater and receiving surface water environments
