In 2026/2027, Onewater, UNESCO's World Water Assessment Programme, United Nations Environment Programme (UNEP), and other partners are turning their lens toward the hidden intersections of water, ecosystems, and human life.

About the contest
This sixth edition's theme, "Out of Sight," spans the full breadth of water and health, how water shapes health, longevity and well-being, and shines its brightest light on the part nobody photographs: wastewater.

Dignified toilets, clean rivers, and the damage untreated sewage causes to people and ecosystems. It also includes the largely unseen work of wastewater surveillance: collecting samples, analyzing what communities flush away and what is circulating in the community, detecting emerging health and ecosystem threats, and turning evidence into early action for animal, people and environmental protection. These are stories that almost never get photographed, because nobody commissions them. That's the heart of Out of Sight, and where this edition's main prize is aimed.

Theme
But the theme is wider than the pipe. Any story about water and health belongs here: the river that cools a city, the ritual bath, the swimming lesson, the river that quietly reveals the pathogens circulating through a community, the tap that finally runs safe. All of it is Out of Sight territory, and all of it can be selected, exhibited and published.

Photo stories should achieve one or more of the following:

Showcase positive solutions in wastewater management — from nature-based treatment systems to circular, resource-recovery innovations that turn wastewater challenges into opportunities.

Explore ecosystem health, showing how clean wetlands, rivers, lakes, and coasts support public health, liveable cities, disease prevention, and sustainable fisheries and livelihoods.
Reveal wastewater surveillance in action, from sampling at treatment plants, drains, hospitals, airports and other transport hubs to laboratory analysis, data interpretation and public-health response. Stories may show how wastewater helps detect pathogens, antimicrobial resistance and other emerging threats while protecting communities without testing every individual.
Celebrate the mental-health, spiritual, and cultural value of blue spaces, revealing water's role in reflection, ritual, and community life.
Document safe drinking water, sanitation, and hygiene as the foundation of healthy lives — across homes, workplaces, schools, sports venues, and care facilities.
Spotlight sports and active living in pools, lakes, rivers, coasts, and community pitches, along with responsible water and sanitation management at major events.