Water is essential to life. Access to clean water and sanitation is vital for healthy societies and ecosystems. It supports all human activities through potable and non-potable uses including drinking water, food production, industrial uses and recreational sports.

In nature water is recycled over and over again. There is no take, make and disposal of water. Water purifies itself endlessly as it flows through the planet’s hydrological cycle. However, nature’s capacity to renew itself is compromised as population growth, pollution and climate change is making water resources scarcer.

Recycled water is wastewater that is treated to a standard suitable for a range of uses. This is increasingly recognised as a potential ‘new’ source of clean water for potable and non-potable uses. End uses for the recycled water often include irrigation for agriculture and recreational sports, fire-fighting, urban cooling, and even supplying people with drinking water.

WHO

RMCG’s expertise intersects agriculture, water, resource recovery, the environment, economics and communities with a focus on regional and rural areas of Australia.

RMCG provides specialist policy, planning and technical consulting services to ensure a healthy future for the environment, industry and communities by helping them to plan and implement change.

As a Certified Benefit Corporation (B Corp), RMCG is part of a global community of businesses that meet high standards of social and environmental impact. RMCG is dedicated to using its resources and influence to create positive social and environmental impact, not just financial success.

RMCG has over 75 staff across six offices in Victoria, Tasmania and New South Wales.

VISION

As water flows through the system from households and industry to sewer it collects chemicals, minerals, nutrients and pathogens that must be treated before the water is either released back to the environment or reused as recycled water.

Before it can be reused, recycled water needs to be treated to a strict standard set by the Environment Protection Authority (EPA) which is appropriate to the purpose of its reuse, with human contact (non-drinking water) requiring the highest regulations. In Victoria, Health and Environment Management Plans (HEMPs) are used to ensure risks to human, animal and plant health are minimised.

RMCG works with industry and government to manage these risks and increase the circularity and value of water.

HOW

RMCG designs fit-for-purpose solutions to supports clients to manage recycled water and align with regulatory requirements.

Key components to the projects generally include:

Avoiding or reducing water use

Opportunities to limit wastewater are often overlooked when designing industrial processes.

Intervening at the design stage of a factory where wastewater volumes are being estimated is a great way to avoid waste before it is generated. In one project, RMCG met with the team designing a food processing plant and noticed that wastewater volumes were very high which would ultimately be hard to manage and expensive for the client. In the final design, wastewater was recycled within the factory, reducing the total volume in the original design by 50 per cent.

Finding fit-for-purpose solutions

When a client’s recycled water scheme cannot achieve the required water quality, RMCG traces this issue up the wastewater treatment plant to find out the source and suggests alternative approaches.

For example, one client’s wastewater treatment process used a phosphate-based salt which limited the ability to reuse the water for irrigation as it posed a risk of eutrophication in the environment. Eutrophication occurs when water has too many nutrients, which can cause plants and algae to grow rapidly and therefore consume high levels of oxygen in the water. In this case, RMCG suggested using another solution which lowered phosphorus and increased the irrigation potential of the water.

Recovering nutrients Recycled water that is used in agriculture can provide extra nutrients that enhance the growth of crops and reduce the need for fertilisers. This requires careful planning as excessive levels of nitrogen, phosphorus and potassium can pose a risk to the environment.

Biosolids (the solid product of wastewater treatment) can also be reused in agriculture. These tend to have a higher recovery rate than recycled water. In 2019 Victoria produced 294,000 tonnes of biosolids, of which 196,500 tonnes were applied to land mostly for agriculture. This can provide costs savings, good agronomic results and lower carbon emissions as a farm is offsetting the use of fertiliser products.

Achieving the highest value for recycled water

Recycled water can be used in different ways, such as watering golf courses, compressing dust in construction, growing pasture crops for animal feed – even fighting fires.

RMCG supports its clients to find the best ways to maximise the value of their recycled water. Recycled water for irrigation is a recurring solution with many agriculture customers.

RESULTS AND BENEFITS

In the 2022-23 financial year, RMCG helped clients recycle more than 15,000ML of treated wastewater through recycled water irrigation in agriculture – this could fill 6,000 Olympic-sized swimming pools.

Lowering greenhouse gas emissions in projects is a constant priority. All water utilities in Victoria have committed to being carbon neutral by 2035 and this is a major consideration when RMCG works with any client and considers options for recycled water or biosolids use. Transporting these for large distances may make the project less viable and increases the carbon footprint.

RMCG aims to use its expertise to support a cultural shift to embrace the circular economy across industries, government and communities in Australia.