Shaping the future: Our strategy for research and innovation in humanitarian response.

A global organisation that finds solutions to complex humanitarian problems through research and innovation..
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Waterborne diseases are among the most significant health threats facing people in refugee and internally displaced persons settlements. Conditions in such sites allow diseases like cholera to flourish. And while chlorination – the most common water treatment method used in emergencies – is inexpensive and effective, its protection fades over time at rates that vary from site to site.

Global guidelines for water treatment do not consider post-distribution chlorine decay. They don’t account for what happens after water is collected, stored and used in the home over many hours, which is typical in humanitarian settings. This gap leaves communities vulnerable to the spread of infectious disease from water that has become re-contaminated after it has left water distribution points. Many outbreaks of waterborne disease in refugee camps have been linked to the recontamination of previously treated water. 


The SWOT is a user-friendly web-based platform that unlocks operational insights from routine water quality monitoring data in humanitarian response settings. It applies cutting-edge modelling techniques to generate evidence-based, context-specific water chlorination targets. This information is critical for understanding public health risks and for identifying actions to improve water safety up to the point of consumption – where it actually matters for public health. We pilot-tested the SWOT in the Cox’s Bazar refugee camps in Bangladesh in 2019 and found that it produced substantive improvements in household water safety compared to the status quo chlorination guidelines.

The SWOT is a low-bandwidth web platform, designed to be accessible in remote and resource-constrained field settings. It’s free to use and comes with an online knowledge base, training and expert technical support.     

In this project, we aim to build evidence that will support the scaling of the SWOT across the global humanitarian sector. Using a mixed-methods approach, we will: 

  1. Evaluate the SWOT in three new humanitarian water supply use cases—water trucking, medical facilities, and surface water supplies 
  2. Improve the robustness of the SWOT’s numerical and machine-learning modelling tools 
  3. Generate insights on how to improve the tool’s use-ability and functionality by learning from field users 
  4. Create rapid tools for evaluating chlorine taste and odour acceptance thresholds and for characterising disinfection by-products in humanitarian water supply projects 


Evaluations have shown that the chlorination targets generated by the SWOT outperform global standards across a range of contexts, including with surface water and groundwater sources, and in piped networks, water trucking operations, and medical facilities.

The innovation has been used by seven humanitarian organisations – including Oxfam, Médecins Sans Frontières, and UNHCR – at 17 sites across nine countries, as part of water systems serving over half a million people. 


The SWOT is a valuable tool wherever water safety may be compromised by pathogenic recontamination. The team is scaling up the innovation and, in response to feedback from WASH teams, is developing new features. These include supporting water quality surveillance across multiple sites for coordinated risk assessment; integrated tools for addressing chlorine taste and odour and disinfection by-product concerns; and modelling the health outcomes of safe water interventions by integrating machine learning and quantitative microbial risk assessment techniques.

Links to more information

Safe Water Optimization Tool (SWOT) wesbite

Key research papers:

Ali, S.I., Ali, S.S. and Fesselet, J.-F. (2015) ‘Effectiveness of emergency water treatment practices in refugee camps in South Sudan’, Bulletin of the World Health Organization, 93(8), pp. 550–558.

Ali, S.I., Ali, S.S. and Fesselet, J.-F. (2021) ‘Evidence-based chlorination targets for household water safety in humanitarian settings: Recommendations from a multi-site study in refugee camps in South Sudan, Jordan, and Rwanda’, Water Research, 189, p. 116642.

De Santi, M. et al. (2021) ‘Forecasting point-of-consumption chlorine residual in refugee settlements using ensembles of Artificial Neural Networks’, npj Clean Water, 4(1).

De Santi, M. et al. (2022) ‘Modelling point-of-consumption residual chlorine in humanitarian response: Can cost-sensitive learning improve probabilistic forecasts?’, PLOS Water, 1(9).

Sudanese refugees collecting chlorinated water supply at the Batil refugee camp, South Sudan, 2013.

Latest Updates

HIF Case Study: Safe Water Optimization Tool

31 Oct 2023

This study was selected by the HIF for our case study series exploring the success and impact of the project.


Using the SWOT to improve water quality in humanitarian settings: Reflections on our work in Somaliland

15 Jan 2023

In this blog, the SWOT Team present the field work conducted at the Las Anod General Hospital in Somaliland in partnership with Médecins Sans Frontières (MSF) where they evaluated how the SWOT could be used to ensure water safety.


First reflections – what have we learned so far?

20 Dec 2022

This post, the third and final in this series, highlights some of the project's early findings and sets out some key lessons learned so far.


New methods for new applications

08 Dec 2022

This post, the second in the series, describes how we’re testing the SWOT out in new water supply use cases, as well as developing new tools for the SWOT toolkit that will provide for a more holistic understanding of water quality.


Kyaka II – Testing New Territory for the SWOT in Uganda

28 Oct 2022

In the first of three in this blog series, the SWOT Team present the field work being carried out in the Kyaka II Refugee Camp in Uganda.


Building the evidence base for the Safe Water Optimization Tool

9 May 2022

The project team is aiming to turn the SWOT prototype into a fully-fledged product, and has identified three important areas of development and testing to ensure the SWOT is ready for widespread adoption in the sector.


WASH Evidence funding granted!

Nov 2020

The project has received further funding from the WASH Evidence challenge to continue building their evidence base.


Evidence-based FRC targets for centralised chlorination in emergencies

31 May 2017

Current emergency water treatment guidelines stipulate free residual chlorine (FRC) levels to protect water at refugee camps from microbiological contamination. However current guidelines are not based on field evidence, and fail to reliably protect water supplies in emergency settings.


Temperature and seasonal effects from chlorine decay: findings from Jordan

13 Sept 2016

Our findings from Azraq Camp, Jordan evidence why it is so important that emergency water treatment guidelines account for local temperature or seasonal weather changes.


Welcome to Sudan: how the research began

15 Apr 2016

In 2013, the Maban County refugee camps in South Sudan faced major outbreaks of Hepatitis E, leading MSF ask two important questions to find out what happened and why.


Stanford Social Innovation Review: How research universities can help the refugee crisis

03 Apr 2016

Academic-humanitarian collaborations that mobilize rigorous scientific research can improve the effectiveness of aid efforts.


Final report - outcomes and impact

31 Oct 2015

This final report outlines the project's key activities and outputs, and includes information on dissemination strategies and partnership development


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