This volume describes the methods used in the surveillance of drinking water quality in the light of the special problems of small-community supplies, particularly in developing countries, and outlines the strategies necessary to ensure that surveillance is effective.

This volume describes the methods used in the surveillance of drinking water quality in the light of the special problems of small-community supplies, particularly in developing countries, and outlines the strategies necessary to ensure that surveillance is effective.

Small drinking-water supplies commonly experience operational, managerial, technical and resourcing challenges that impact their ability to deliver safe and reliable services. The needs and opportunities associated with these supplies therefore warrant explicit consideration in policies and regulations. These Guidelines, specifically tailored to small water supplies, build on over 60 years of guidance by the World Health Organization (WHO) on drinking-water quality and safety. They focus on establishing drinking-water quality regulations and standards that are health based and context appropriate; on proactively managing risks through water safety planning and sanitary inspections; and on carrying out independent surveillance. The guidance is intended primarily for decision-makers at national and subnational levels with responsibility for developing regulatory frameworks and support programmes related to these activities. Other stakeholders involved in water service provision will also benefit from the guidance in this document. Designed to be practical and accessible, these Guidelines offer clear guidance that is rooted in the principle of progressive improvement. State-of-the-art recommendations and implementation guidance are provided, drawn from a comprehensive evidence review and established good practices. Additionally, case examples are provided from countries and areas around the world to demonstrate how the guidance in this publication has been implemented in practice in a wide variety of contexts. Together with WHO’s 2024 Sanitary inspection packages – a supporting tool for the Guidelines for drinking-water quality: small water supplies, these Guidelines update and supersede WHO’s 1997 Guidelines for drinking-water quality. Volume 3: surveillance and control of community supplies. Key changes to this updated publication include a greater focus on preventive risk management and a broader range of small water supplies covered, including those managed by households, communities and professional entities.

This is the third edition of the WHO's guidelines which are used by countries worldwide to set standards for the regulation of drinking water quality and effective approaches to water safety management. This revised edition has been updated to take account of recent developments in risk assessment and management. Topics discussed include: a framework for drinking water safety and discussion of the roles and responsibilities of different stakeholders, such as national regulators, water suppliers and independent surveillance agencies; guidance on microbial safety of drinking water through safety plans; new scientific information on chemicals, waterborne pathogens and individual chemical hazards of actual or potential concern. It also considers the application of the guidelines in specific circumstances, such as in emergencies and disasters, and to specific applications, such as bottled water. It also contains information on over 130 documents which substantiate or explain the content of the Guidelines, and on good practice guidance in achieving drinking-water safety.

Small communities violate federal requirements for safe drinking water as much as three times more often than cities. Yet these communities often cannot afford to improve their water service. Safe Water From Every Tap reviews the risks of violating drinking water standards and discusses options for improving water service in small communities. Included are detailed reviews of a wide range of technologies appropriate for treating drinking water in small communities. The book also presents a variety of institutional options for improving the management efficiency and financial stability of water systems.

Legionnaires' disease, a pneumonia caused by the Legionella bacterium, is the leading cause of reported waterborne disease outbreaks in the United States. Legionella occur naturally in water from many different environmental sources, but grow rapidly in the warm, stagnant conditions that can be found in engineered water systems such as cooling towers, building plumbing, and hot tubs. Humans are primarily exposed to Legionella through inhalation of contaminated aerosols into the respiratory system. Legionnaires' disease can be fatal, with between 3 and 33 percent of Legionella infections leading to death, and studies show the incidence of Legionnaires' disease in the United States increased five-fold from 2000 to 2017. Management of Legionella in Water Systems reviews the state of science on Legionella contamination of water systems, specifically the ecology and diagnosis. This report explores the process of transmission via water systems, quantification, prevention and control, and policy and training issues that affect the incidence of Legionnaires' disease. It also analyzes existing knowledge gaps and recommends research priorities moving forward.