Wastewater-based epidemiology was widely used to monitor the spreading of COVID-19. We should now build on the knowledge acquired over the past three years to extend the use of the technique to a wide range of human health and lifestyle aspects.

Treatment of brackish groundwater can help to alleviate potential competition for freshwater resources between the power sector and other sectors in water-stressed regions.

The approach based on analysing wastewater to monitor drugs or pathogens in the population had been used for decades before it became widespread during the COVID 19 pandemic. We have asked experts located in a number of different nations to share their views on the potential and limitations of wastewater-based epidemiology in the future.

This study reveals trade-offs in freshwater savings, cost and capacity shortfalls from deploying treated brackish water for wet thermoelectric cooling, as well as its cost-effectiveness, relative to dry cooling retrofit, in saving freshwater.

The successful use of wastewater-based data during the COVID-19 pandemic has led to the creation of the National Wastewater Surveillance System in the USA for pathogen monitoring. Now a complementary system is needed for help tackling the opioid epidemic.

Heterogeneous water disinfection is a promising way to avoid secondary pollution, but it is not very efficient. The development of nanoflakes shows that a much higher efficiency than previously achieved can be achieved through solar-driven heterogeneous disinfection.

Wastewater surveillance enables tracking infectious disease dynamics and community prevalence quantification for public health. However, the testing requirement of centralized laboratories and well-trained staff challenges underserved areas and low-resource settings. The development of new rapid and low-cost sensors enables in-field testing of wastewater from the community to the individual building levels for early warning of pandemics.