Monitoring sanitation and wastewater services for the Sustainable Development Goals

The United Nations Sustainable Development Goals (SDGs) include ambitious global targets for drinking water, sanitation and wastewater services. The indicator for SDG target 6.2, ‘use of safely managed sanitation services’ and for SDG target 6.3 ‘wastewater safely treated’, seek to go beyond the toilet to ensure that sanitation services protect public health and the environment. Countries have now begun to address data gaps along the sanitation service chain and to strengthen the monitoring of wastewater treatment and reuse. This includes addressing a major data gap on the management of onsite sanitation services, such as septic tanks and latrines.  

This collection of papers – a collaboration between the WHO/UNICEF Joint Monitoring Programme for Water Supply, Sanitation and Hygiene, UN-Habitat and npj Clean Water – will broadly explore efforts to monitor the full sanitation chain from containment, transport, treatment and final disposal or reuse. Studies examining inequalities in exposure to the impacts of inadequate sanitation and wastewater treatment, focused on vulnerable populations such as those living in refugee or IDP settings, and the specific sanitation and wastewater services needs of women and girls and persons living with disabilities are strongly encouraged. Submissions are equally encouraged from low-, middle- and high-income countries.

npj Clean Water is a new Nature Research journal and is part of the Nature Partner Journal family. The journal is open access, ensuring that all papers in this collection will be freely available, enabling wide readership. See the journal website for information about article processing charges (APC). APCs may be waived or reduced for certain institutional partners, or for papers whose corresponding authors are based in countries classified as low-income or lower-middle-income economies. Nature offers funding and support services for authors to discover and apply for funding to cover APCs. The deadline for submissions is February 1, 2024 and papers will be published on the journal website as soon as they are accepted, and then additionally gathered together on a unique webpage.


Modern urban waste water treatment plant.


  • Rick Johnston

    Group Leader, Department of Environment, Climate Change and Health (ECH), WHO/UNICEF

  • Tom Slaymaker

    Sr Statistics & Monitoring Specialist (WASH), UNICEF

  • Graham Alabaster

    Chief, Waste Management and Sanitation, UNHABITAT

  • Andrew Shantz

    Freelance Consultant, World Health Organization

  • Pay Drechsel

    Senior Fellow, International Water Management Institute (IWMI), Sri Lanka

  • Alison Parker

    Senior Lecturer, Centre for Water, Environment and Development, Cranfield University, UK

  • Charles Niwagaba

    Associate Professor, Civil and Environmental Engineering, Makerere University, Uganda‎

  • Juliet Willetts

    Research Director, Institute for Sustainable Futures (UTS-ISF), University of Technology Sydney, Australia

Rick Johnston is a Group Leader in Department of Environment, Climate Change and Health (ECH). He leads the WHO half of the WHO/UNICEF Joint Monitoring Programme for Water Supply, Sanitation and Hygiene. Before joining WHO in 2013 he worked at Eawag: the Swiss Federal Institute of Aquatic Science and Technology, and at UNICEF. He has over 25 years of experience on WASH in low- and middle-income countries, with a focus on monitoring and drinking water quality. He graduated from Grinnell College and holds degrees in environmental engineering from the Johns Hopkins University and the University of North Carolina at Chapel Hill.

Tom Slaymaker is the Sr Statistics & Monitoring Specialist (WASH) in UNICEF. He has 18 years’ experience working in the field of international development engaged in public policy and advocacy on aid, public policy and poverty reduction in Africa and Asia. He is an internationally recognised water sector expert specialising in the development of water, sanitation and hygiene (WASH) services including rights-based approaches, governance and institutional development, pro-poor sector reform processes, and service delivery in difficult environments.


Graham Alabaster is the Chief of Waste Management and Sanitation. He is also an Engineer by profession, with first degree in Chemical Engineering and a PhD in Civil Engineering. He joined UNHABITAT in 1992 and has played a key role in building the Water, Sanitation and Infrastructure Branch. He was the agency representative on the WHO Panel of Experts for the Environmental Control of Vector-borne Diseases (PEEM), with a special interest in urban vector-borne diseases. He has over 25 years experience in the water sanitation and solid waste management working in over 30 countries.


Andrew Shantz is a Freelance Consultant and has worked with the World Health Organization since 2020 to support the monitoring of SDG Indicator 6.3.1 on safely treated wastewater. Andrew has 15 years of experience working on rural water supply, drinking water quality, arsenic mitigation, household water treatment, rural sanitation, and WASH monitoring. He holds a BSc. in Environmental Engineering from the University of Waterloo and an MSc. in Epidemiology from the London School of Hygiene and Tropical Medicine.


Pay Drechsel holds a PhD in Environmental Sciences, University of Bayreuth, and is a Senior Fellow at the International Water Management Institute (IWMI). With over 30 years of professional experience, Pay has been working extensively in the rural-urban interface of low-income countries, coordinating projects and programs on the safe recovery of water and nutrients from domestic waste streams, with a special interest in safe wastewater irrigation, urban and peri-urban agriculture, and applied inter-disciplinary research. In 2015, Pay’s work was recognized by the International Water Association with the IWA Development Award for Research.

Alison Parker completed a four year Masters degree at the University of Oxford in Earth Sciences.This was followed by a PhD at the University of Leeds studying the hydrogeology of the chalk aquifer of East Yorkshire. Dr Parker started as a Research Fellow at Cranfield University in January 2009 and was progressed to Senior Lecturer by October 2019. Her current research portfolio centers on the circular economy for sanitation and managed aquifer recharge.


Charles B. Niwagaba is an Associate Professor of Civil and Environmental Engineering at Makerere University. He holds BSc. Civil Engineering and MSc. from Makerere University; and PhD in Environmental Technology from the Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden. He has 22 years of experience in research, teaching and consultancy in Civil and Environmental Engineering. Dr. Niwagaba has been involved in various research and consultancies funded locally by Government of Uganda and by various multi-lateral agencies. Dr. Niwagaba has extensive knowledge in development of innovative practices in sanitation improvement (from Engineering, social marketing to financing); solid waste management with emphasis on recycling and re-use e.g. composting, biogas, grey water treatment and use, application of faecal sludge in industrial kilns and boilers, design of faecal sludge treatment plants etc. 

Juliet Willetts is Research Director at University of Technology Sydney’s Institute for Sustainable Futures (UTS-ISF). She leads applied research to inform water and sanitation policy and practice in Asia and the Pacific, including urban sanitation, rural sanitation and rural water-supply. Her contributions cover climate change, governance, technical solutions, gender equality and sector monitoring, through partnerships with governments, UN agencies and bilateral, multilateral and civil society organisations. She has been recognised by multiple awards, including Australian Financial Reviews’ 100 Women of Influence. She holds a PhD from the University of NSW in Environmental Engineering and published more than 130 peer-reviewed articles.