Treating wastewater with anammox

At the Luggage Point Resource Recovery Centre in Brisbane, Queensland, Australia’s largest sewage treatment facility has made a significant breakthrough in wastewater treatment: the cultivation and use of anammox bacteria — microscopic organisms sometimes called “poo-eating superbugs.” These microbes play a pivotal role in cleaning sewage by naturally converting harmful nitrogen compounds into harmless nitrogen gas, and their adoption promises both environmental and economic benefits for countries like the Philippines.

Wastewater cleaner

Anammox stands for anaerobic ammonium oxidation — a biological process where specialized bacteria consume ammonium and nitrite in wastewater and convert them directly into nitrogen gas. This is done without oxygen, no added carbon, and with much less energy than traditional nitrogen removal methods.

Growing and applying anammox bacteria commercially is no small feat. At Urban Utilities, scientists and engineers spent more than a decade cultivating enough of these slow-growing microbes. At first, they had barely enough to fill a jam jar; eventually they grew enough to fill the volume of 10 backyard swimming pools — enough to treat large volumes of Brisbane’s sewage.

Anammox bacteria are mainly from the genera Candidatus Brocadia, Candidatus Kuenenia, and Candidatus Scalindua. The first is most common in municipal wastewater treatment plants and the second are found in lab reactors and sidestream treatment. The third is dominant in marine and coastal environments.

Cost-effective treatment

Since integrating anammox into the treatment process at Luggage Point, Urban Utilities has seen significant operational advantages:

Reduced energy use: Because anammox doesn’t rely on oxygen-driven processes, energy needed for aeration is cut dramatically — by up to 60 percent compared with conventional nitrogen removal methods.

Lower chemical inputs: Traditional nitrogen removal often requires added chemicals (like carbon sources); with anammox, these are no longer needed, saving both cost and handling risks.

Financial savings: Urban Utilities estimates roughly 500,000 Australian dollars (over P20 million) in annual operating cost savings thanks to anammox’s efficiency.

Increased capacity: The improved process not only treats sewage more sustainably but also creates about 10 percent extra effective capacity for handling population growth.

Furthermore, the technology is now being shared with other utilities across Australia, creating a biofarm of useful anammox cultures for future plants.

Beneficial bacteria

The Philippines faces growing wastewater challenges in urban centers like Metro Manila, Cebu and Davao, where rapid population growth and limited sanitation infrastructure can lead to polluted rivers, coastal waters, and public health concerns. Introducing anammox-based treatment could offer several benefits:

Energy savings and lower costs

Conventional wastewater treatment in the Philippines relies on energy-intensive aeration systems. Anammox can cut energy costs drastically, which is especially significant in a country where electricity costs are comparatively high and utilities are under pressure to keep rates affordable.

Reduced chemical use

Municipalities often add carbon sources or other chemicals to achieve nitrogen removal. Anammox eliminates the need for these, making treatment less expensive and simpler to manage, particularly for smaller wastewater plants with limited budgets.

Environmental protection

Nitrogen pollution contributes to eutrophication — excessive algae growth that depletes oxygen in water bodies, killing fish and harming ecosystems. Anammox’s efficient nitrogen removal helps protect rivers, lakes, and coastal areas that are vital to Filipino communities and livelihoods.

Scalability and growing populations

Urban Utilities’ experience shows that anammox can create extra treatment capacity without massive infrastructure expansion — a valuable trait for rapidly growing cities in the Philippines.

Implementation considerations

Despite the benefits, adopting anammox isn’t plug-and-play. The bacteria are slow-growing and sensitive to environmental conditions, so proper laboratory cultivation and treatment design are essential. Plants would need technical support — potentially from universities, technology partners, or collaborative research — to replicate what Urban Utilities has accomplished.

Australia’s experience with anammox bacteria at Urban Utilities demonstrates how bioengineered nature can make sewage treatment cleaner, cheaper and more efficient. For the Philippines, where wastewater challenges are significant and resources are constrained, investing in anammox technology could help protect water resources, reduce treatment costs and support sustainable urban growth.