Safe Water for Every Home: WHO’s Global Framework for Sustainable Drinking Systems

The WHO’s Compendium of Drinking-water Systems and Technologies from Source to Consumer provides a global blueprint for ensuring safe, equitable, and sustainable drinking-water systems through science-based, context-specific technologies. It emphasizes source protection, effective treatment, resilient distribution, and inclusive governance to secure clean water for all.

The study "World Health Organization’s Compendium of Drinking-water Systems and Technologies from Source to Consumer," created with research contributions from the Swiss Federal Institute of Aquatic Science and Technology (Eawag), the University of Surrey, the University of Queensland, and several national water and health research institutes, serves as one of the most comprehensive guides ever assembled on safe water supply. It combines engineering science, environmental management, and public health insights to document technologies that carry water safely from its natural source to the consumer’s tap. The compendium arrives at a critical time, when billions of people worldwide still lack access to safely managed drinking water. Its purpose is not only to describe technologies but also to guide decision-making, ensuring that water supply solutions are technically sound, economically feasible, and socially inclusive.

Guarding the Source: The First Line of Defense

The compendium begins where every drop of clean water originates, the catchment. It stresses that the integrity of drinking water depends first and foremost on protecting natural sources such as rivers, aquifers, and rainwater systems. The text draws on research showing how deforestation, industrial waste, and agricultural runoff compromise water quality long before it reaches treatment facilities. WHO and its research partners advocate watershed management, pollution control, and land-use zoning as essential preventive measures. The document highlights that investment in source protection is far more cost-effective than post-contamination treatment, using examples like vegetative buffer zones and sanitary protection areas. Prevention, it declares, is both the most affordable and the most sustainable form of water treatment.

Treatment Technologies: Turning Science into Safety

The core of the compendium is a sweeping exploration of water treatment technologies, ranging from community-level interventions to large-scale municipal systems. It systematically examines methods such as coagulation, sedimentation, rapid and slow sand filtration, and a variety of disinfection processes, including chlorination, ozonation, and ultraviolet (UV) radiation. Each technique is described in terms of operational principles, contaminant removal efficiency, cost, and maintenance needs. The report cites successful deployments such as gravity-fed systems in Nepal’s mountain regions, solar disinfection units in rural Africa, and membrane filtration plants in Asia’s megacities. The key message is that no technology is universal; context matters. What works for a dense urban settlement may not suit an isolated community relying on rainwater. Hence, decisions must be guided by local hydrology, institutional capacity, and user behavior.

Distribution and Storage: The Silent Risk Zone

The compendium warns that even the best treatment systems can be rendered ineffective by poor distribution. Leaks, intermittent supply, and cross-connections can lead to recontamination, sometimes making water more hazardous than when it left the source. WHO recommends continuous pressurization of systems, periodic leak detection, and maintenance of residual disinfectant levels as standard safety measures. The report also points to innovations in smart monitoring, digital sensors, and real-time data systems that detect contamination or infrastructure failures before they pose a public health threat. Household storage practices receive special attention too, particularly in rural and peri-urban areas. Simple design improvements, like narrow-mouthed containers and covered tanks, can prevent microbial growth and preserve residual chlorine, reducing disease transmission within homes.

Sustainability, Climate Resilience, and Equity

Beyond the pipes and filters, the compendium situates water technology within the larger challenges of climate change, energy scarcity, and social equity. It emphasizes life-cycle costing, considering not just installation but also maintenance, energy demand, and long-term affordability. Climate change, the report notes, is forcing a rethinking of conventional water systems as droughts, floods, and salinity intrusion reshape water availability. It recommends decentralized systems powered by renewable energy, rainwater harvesting, and efficient reuse as the next frontier of resilient water management. Equity runs through the report as a moral thread. Safe water, it asserts, is not a luxury but a right. Technologies must therefore be designed to reach marginalized groups, including those in informal settlements and remote rural communities. The compendium also recognizes the indispensable role of women in community-based water management, citing successful projects where women’s cooperatives operate and maintain local supply schemes.

The Path Ahead: Knowledge, Governance, and Trust

The report offers a message of pragmatic optimism. The science and technology needed to secure safe water are already available; what is missing is coordination, capacity, and commitment. The WHO urges countries to adopt an integrated approach based on its Water Safety Plan framework, combining risk assessment, surveillance, and community engagement. The document calls for governments and institutions to treat the compendium as a living reference, updating it with new data and innovations. It envisions a future where every community can access safe, affordable, and resilient water systems, guided by principles of transparency, sustainability, and shared responsibility. The compendium closes with a conviction that water security is not just about infrastructure; it is about trust, governance, and the collective will to ensure that when someone opens a tap anywhere in the world, they can do so without fear.