A Holistic Approach to Improving Water, Sanitation, and Public Health

Despite COVID-19 putting a spotlight on the importance of water, sanitation and hygiene, over 2 billion people still do not have basic sanitation facilities. Photo credit: ADB.

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Best practices in WASH initiatives consider the needs, culture, and behaviors of the poor and vulnerable who are most at risk of infectious diseases.


The coronavirus disease (COVID-19) has brought the stark realization of the critical role of preventative health in protecting economies and societies.

As the pandemic continues to sweep the globe, the need to immediately address vulnerabilities and inequalities to ensure safe water, sanitation, and hygiene (WASH) has become more critical than ever for infection prevention and control. It is the primary line of defense against the spread of COVID-19 and water-borne diseases.

A Health Crisis

Poor water quality and inadequate sanitation are related to some of the most serious health risks around the world. Estimates indicate that even before COVID-19, the annual global toll from bacteria-related diarrheal diseases is at 820,000 deaths and 50 million disability-adjusted life years (DALYs) while respiratory disease causes 370,000 deaths and 17 million DALYs. DALY is a measure of the sum of years of potential life lost due to premature mortality and the years of productive life lost due to disability.

Other WASH-related health problems linked to poor sanitation include ascariasis (human worm infection), trachoma (infectious disease causing blindness), and schistosomiasis (parasitic disease). Chronic health issues linked to inadequate water, sanitation, and hygiene also include antimicrobial resistance and stunting.

The World Health Organization (WHO) has declared antimicrobial resistance as one of the top 10 global public health threats. Adequate WASH and wastewater treatment from households, livestock, and other industries can reduce environmental drivers of antimicrobial resistance.

Poor sanitation is the second leading risk factor for stunting worldwide. The link between undernutrition, failure to thrive, and stunting with enteric diseases has been a major focus of WASH researchers and funders over the last decade.

Access to safe water and proper sanitation, which are critical control measures against COVID-19, remain major challenges in many countries. Ensuring that adequate sanitation is in place and quality drinking water meets microbiological and chemical standards can protect an individual’s health from an array of chronic and acute water-related diseases.

Multipronged Solutions

WASH practitioners from government, private sector, and civil society face an array of implementation challenges when working toward improving water, sanitation, and hygiene, and health.

Issues on funding, institutional and policy settings, human capacity, and behavioral and societal norms can help or hinder WASH initiatives. In such complex context, multipronged approaches are needed to ensure effective and sustained WASH investments and achieve the targeted health and disease reduction outcomes.

The following recommendations can help practitioners address some of the common challenges when implementing WASH interventions:

Globally, over 2 billion people still do not have basic sanitation facilities and 785 million people lack basic drinking water services. In Southeast Asia, 40% of households and 50% of schools do not have access to handwashing facilities.

The complex interaction between poverty and service insecurity, such as water and sanitation, can compromise public health in urban areas. Lower socioeconomic groups typically suffer worse health outcomes. For example, populations that suffer most from neglected tropical diseases are also those who lack adequate water and sanitation.

Extra steps, such as setting targets to reach the poor, are often needed to ensure investments meet the needs of specific groups. The Asian Development Bank’s (ADB) Handbook on Poverty and Social Analysis provides information in designing pro-poor initiatives.

Comprehensive poverty and social impact analyses during project design stages can ensure that gender, socioeconomic, ethnic, disability, and other vulnerabilities are considered. In the Xinjiang Urban Transport and Environmental Improvement Project in the People’s Republic of China, consultation processes resulted in adjustments in the sitings and public sanitation facility designs to increase access, privacy, and combine toilets and baths. It included a targeted effort to address gaps in sanitation services for poor and largely ethnic minority communities. In Altay City in the Xinjiang Uygur Autonomous Region, 53% of ethnic minority households eventually had access to indoor flush toilets compared to only 10% prior to the project’s implementation.

Urban sanitation and water infrastructure projects tend to be technical and engineering-focused interventions with less emphasis on how beneficiaries use the services, hygiene behavior change, and health impacts. Institutional support and capacity building are important to a project’s sustainability, helping ensure the continuity of services that is core to safeguarding one’s health.

A review of ADB-supported sanitation initiatives found that success factors related to urban initiatives include long-term relationships for policy dialogue, national campaigns for investment in sanitation, and encouraging demonstration effects of pilot fecal sludge management at municipality level. Failure factors include lack of targets for the poor in inclusive planning and not monitoring environmental and health impacts. These findings highlight the importance of the nonengineering aspects of initiatives and their contributions to sustainability. Building capacity in management, financing, and technical areas, including institutional support components, consulting communities consultation, and conducting comprehensive poverty and vulnerability assessments are all steps toward broadening and encouraging a more holistic view of urban sanitation and water infrastructure.

The Ebeye Water Supply and Sanitation Project in the Marshall Islands is an example where a range of nonengineering interventions were essential to the sustainability of the physical investments. Hygiene awareness, education programs, and capacity building initiatives were critical to the success of the project, which included a new desalination plant, new sewage treatment facilities, a marine outfall, and upgraded and expanded water supply distribution and sewerage systems. The hygiene program was conducted in partnership with schools, women’s groups, and nongovernment organizations.

During the COVID-19 pandemic, ensuring the continuity of water supply is especially important so people can wash hands regularly and properly.

To ensure behavior change programs suit particular audiences, these must be based on formative research and contextual knowledge. Formative research can help identify other effective behavioral determinants (e.g., social affiliation, pride, disgust). This knowledge combined with multipronged campaigns, conducive physical environments, sufficient resources, and trained personnel can support effective behavior change. There are numerous tools and knowledgeable practitioners available to support program designers and implementers in this endeavor.

WASH-related hygiene behaviors to target include: (i) sanitation hygiene, use of a latrine, and safe disposal of human feces; (ii) water hygiene and use and protection of safe water sources and household water treatment; (iii) personal hygiene, hand hygiene, and menstrual hygiene; and (iv) food hygiene and proper food preparation and handling.

The ADB-supported South Tarawa Water Supply Project in Kiribati, which finances piped water system and management improvements, also includes a hygiene component targeting a range of WASH behaviors, such as handwashing with soap, proper treatment of household water and its safe storage, and menstrual hygiene management. Overcrowding and inadequate WASH coverage contributed to waterborne diseases in the community.

Institutional complexity can hamper project implementation. Collaborative fora where various health and water-related players meet and discuss challenges have been shown to be effective in helping address preventative health issues that might otherwise fall between the gaps.

An example of multisectoral collaboration is the Bangladesh Urban Primary Health Care Services Delivery Project, which combines primary health care services, community hygiene behavior change programs, and a climate change resilience component under the Urban Climate Change Resilience Trust Fund. At the institutional level, the project supports city and municipal health departments to develop organizational charts and reorganization plans, integrating these with other health determinants and related climate-sensitive subsectors (e.g., water, sanitation, and waste management) in a holistic manner to improve public health. The project has worked across sectors to ensure WASH, and electricity/solar energy backup in health care facilities.

Mapping a Way Forward

Sanitation and water infrastructure investments should go hand in hand with hygiene initiatives to achieve the best health outcomes.

Diagram shows the foundational role of a well-designed water and sanitation infrastructure. Diagram by Bronwyn Powell.

Access to safe water and sanitation infrastructure is fundamental to assuring peoples’ health. To maximize the proper use of such infrastructure, it must be needs-focused, pro-poor, and cognizant of the users’ cultures and behaviors.

In addition, WASH projects should consider people’s attitudes and provide targeted hygiene behavior change programs.

At the macro level, improving people’s health has broad benefits through increased social and economic participation. Healthy people can better engage in economic and social activities and reach their full potential. Increased participation also reduces poverty and inequalities and contributes to women’s economic empowerment. 

The effects of the COVID-19 pandemic clearly show the need to take additional steps to expand the coverage and improve the effectiveness and targeting of WASH initiatives to reach the poor and vulnerable. The steps outlined in this article can help practitioners prioritize and broaden efforts, coordinate between sectors, and more comprehensively and effectively address hygiene interventions.


A. Ellis, J. Stoler, and Y. Adams. 2019. Water Insecurity and Urban Poverty in the Global South: Implications for Health and Human Biology. American Journal of Human Biology. 32 (1).

A. Prüss-Ustün et al. 2019. Burden of Disease from Inadequate Water, Sanitation and Hygiene for Selected Adverse Health Outcomes: An Updated Analysis with a Focus on Low and Middle-Income Countries. International Journal of Hygiene and Environmental Health. 222 (5). pp. 765–777.

ADB. 2021. Economic Analysis at Completion: Water Supply, Solid Waste, Sanitation, and Flood Prevention Projects. Manila.

Asian Development Bank (ADB). 2012. Handbook on Poverty and Social Analysis: A Working Document. Manila.

Independent Evaluation Department. 2018. Leading Factors of Success and Failure in Asian Development Bank Urban Sanitation Projects. Manila: ADB.

S. Boisson et al. 2016. Water, Sanitation and Hygiene for Accelerating and Sustaining Progress on Neglected Tropical Diseases: A New Global Strategy 2015–20. International Health. 8 (Suppl 1). pp. i19–i21.

United Nations Children’s Emergency Fund (UNICEF). 2020. Overview of Water, Sanitation and Hygiene (WASH) COVID-19 Responses from Governments, Regulators, Utilities and other Stakeholders in 84 Countries. New York.

United Nations Development Programme. 2020. Leaving Poverty Behind: Using Multidimensional Poverty Measures to Tackle Poverty and Achieve the SDGs in Asia and the Pacific. Bangkok.

WaterAid. 2019. Practical Pathways to Integrate Nutrition and Water, Sanitation and Hygiene (WASH).

World Bank. 2020. The Human Capital Index 2020 Update: Human Capital in the Time of COVID-19. Washington, DC.

World Health Organization (WHO). 2020. Anti-Microbial Resistance.  

WHO/UNICEF. 2020. Water, Sanitation, Hygiene, and Waste Management for SARS-Cov-2, The Virus That Causes COVID-19: Interim Guidance.


Bronwyn Powell
WASH and Health Specialist Consultant, Asian Development Bank

Bronwyn Powell has over 20 years of experience in the development sector across Asia and the Pacific. Her expertise includes the social and governance dimensions of water, sanitation, and hygiene (WASH), integrated water resources management, community engagement, health, and nutrition. She has worked with Australia’s Department of Foreign Affairs and Trade, United States Agency for International Development, and World Bank. She is also an associate of the International WaterCentre at Griffith University in Australia. 

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Coral Fernandez-Illescas
Former Principal Water Resources Specialist, Sustainable Development and Climate Change Department, Asian Development Bank

Dr. Coral Fernandez-Illescas is a civil and environmental engineer with over 24 years of experience in the water and sanitation sector, including water, sanitation and hygiene (WASH), and water resources management arena in international development (Asian Development Bank and Inter-American Development Bank) and academia (Harvard University and Princeton University). She holds a PhD in Civil and Environmental Engineering from Princeton University and an M.Eng. in Civil and Environmental Engineering from Imperial College of Science, Technology and Medicine. 

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