We are delighted to share the final Open Access Week Spotlight Blog!

Our OA Ambassadors raise awareness in their local communities about global OA movements as well as related opportunities through IWA Publishing. They are representatives of both the International Water Association and IWA Publishing and our joint goals to empower the next generation of water leaders and to shape the future of the water sector. These blog posts highlight their specialty and research focus, as well as emphasising the importance of Open Access publishing. 

The latest blog is written by Abdurrahman Aliyu, an MSc student at the Pan-African University Institute for Water and Energy Sciences, whose research covers the recovery of resources from wastewater, rainwater harvesting, and nature-based solutions. Connect with Abdurrahman on LinkedIn.

Traditionally, wastewater treatment has been focused on removing contaminants and pathogens to recover water and safely discharge it into the environment. However, the circular economy offers a new approach to wastewater management, one that views wastewater as a valuable resource rather than a waste product.

In a circular economy, wastewater treatment plants become resource recovery facilities. They extract energy, clean water, fertilizers, and nutrients from wastewater and use them for beneficial purposes. This approach can help to achieve the Sustainable Development Goals (SDGs) by reducing water pollution, improving resource efficiency, and creating new economic opportunities.

Why is a circular economy approach to wastewater management important?

Population and economic growth have driven a rapid rise in demand for water resources. As a result, 36% of the world’s population already lives in water-scarce regions. Especially in low- and middle-income countries, rapid urbanization has created various water-related challenges, including degraded water quality and inadequate water supply and sanitation infrastructure. As cities continue to grow, there is an opportunity to ensure that investments are made in the most sustainable and efficient way possible. Future urban development requires approaches that minimize resource consumption and focus on resource recovery, following principles of the circular economy

A circular economy approach to wastewater management can help to address these challenges by:

• Reducing water pollution: Wastewater treatment plants that recover and reuse resources can help to reduce the amount of pollutants discharged into the environment. This can improve water quality and protect aquatic ecosystems.
• Improving resource efficiency: By recovering and reusing resources from wastewater, a circular economy approach can help to reduce the demand for freshwater and other resources. This can help to conserve natural resources and make communities more resilient to climate change.
• Creating new economic opportunities: Recovered resources from wastewater can be used to produce new products and services, such as recycled water, bioenergy, and biofertilizers. This can create new jobs and boost the economy.

How can we implement a circular economy approach to wastewater management?

There are a number of ways to implement a circular economy approach to wastewater management. Some examples include:

• Reclaiming water: Reclaimed water is wastewater that has been treated to a high standard and can be reused for non-potable purposes, such as irrigation, industrial cooling, and toilet flushing.
• Recovering nutrients: Nutrients such as nitrogen and phosphorus can be recovered from wastewater and used to produce biofertilizers. This can help to reduce the need for synthetic fertilizers, which can pollute waterways.
• Generating energy: Biogas, which is a methane-rich gas, can be produced from wastewater and used to generate electricity or heat. This can help to reduce the reliance on fossil fuels and make wastewater treatment plants more energy self-sufficient.

Case studies of the Circular Economy in Wastewater Management

Here are a few case studies of wastewater treatment plants that are implementing the circular economy:

Windhoek, Namibia: Windhoek is the capital of Namibia, which is Southern Africa's most arid country. In 1960, Windhoek became the first city in the world to reclaim its wastewater back to potable water quality for use in the reticulation system. This is done using a process called direct potable reuse (DPR). DPR is a highly advanced wastewater treatment process that produces water that is safe to drink and meets all drinking water standards.

Strass TP and Wolfgangsee-Ischl, Austria: These two wastewater treatment plants generate more energy than they use. They do this by using anaerobic digestion to convert biosolids into biogas. The biogas is then used to generate electricity, which powers the plants and other facilities in the area.

East Bay Municipal Utility District (EBMUD) wastewater facility, Oakland, CA: This wastewater facility became the first energy-neutral wastewater treatment plant in North America in 2012. It achieves this by using a variety of energy-efficient technologies, including solar panels and anaerobic digestion.

The circular economy is a new approach to wastewater management that has the potential to reduce the environmental impact of wastewater treatment and create new economic opportunities. However, there are a number of challenges to implementing the circular economy, such as the need to invest in new technologies and infrastructure and the need to change public perceptions of wastewater.

Despite the challenges, the case studies above show that it is possible to implement the circular economy in wastewater management. These case studies provide examples of how wastewater treatment plants can recover and reuse resources, reduce their environmental impact, and generate revenue. The circular economy is a promising approach to wastewater management that has the potential to create a more sustainable future.