We are Elrha, a force for change in the humanitarian community. The research and innovation we support equips the humanitarian community with the knowledge of what works, so people affected by crises get the right help when they need it most.
Our purpose is clear: to empower the humanitarian community to improve humanitarian response. We make this happen by supporting and championing the outcomes of robust research and proven innovations.
We empower the humanitarian community. Find out how we can support you...


Current humanitarian water chlorination guidelines (i.e., Sphere) fail to ensure water safety at the point-of-consumption in many emergency settings. This has significant public health implications as drinking water is a primary pathway by which faecal-oral diseases are transmitted (e.g., cholera, hepatitis E, diarrhoeal diseases). Failure to ensure adequately chlorinated drinking water up to the point-of-consumption leaves water at risk for being recontaminated. Multiple studies have shown that post-distribution recontamination of water is linked to the spread of waterborne diseases among displaced populations in camp settings.


In response to this need, we created the Safe Water Optimization Tool (SWOT), a web-based data analytics platform that generates site-specific and evidence-based water chlorination targets that outperform the Sphere chlorination target with respect to household water safety. The SWOT uses machine learning and numerical modelling, housed in a user-friendly and low-bandwidth online platform, to extract life-preserving information from routine water quality monitoring data.

In this project, we will build evidence to support scaling the SWOT by demonstrating its water safety impact and by improving its effectiveness and useability. Through a mixed method approach, we will: i) demonstrate the SWOT’s water safety effectiveness in multiple humanitarian water supply use cases; ii) improve analytics robustness to handle data of varying quality/quantity and ease field data collection requirements; iii) improve functionality and UX/UI of the web platform to enhance useability; and iv) incorporate tools for managing chlorine taste/odour acceptability and disinfection by-products.


1.Rigorous evaluations of household water safety effectiveness of the SWOT versus the status quo Sphere guidelines, in multiple use cases including surface water systems, water trucking, household water treatment programs, and/or medical facility water systems, conducted by an arms-length research partner.
2. A new improved version of the SWOT that is able to generate effective outputs using less and lower-quality field data, which is cheaper and easier for fieldworkers to collect; plus, additional user functionalities and improved UX/UI in response to feedback from field users.
3. New tools in the SWOT toolkit for rapid evaluation of chlorine taste/odour acceptance/rejection thresholds and for disinfection by-products risk characterization in humanitarian operations.
4. Technical memoranda for practitioners and policy briefs for donors and policymakers regarding quality assurance using the SWOT on humanitarian water supply projects.
5. Scientific publications, conferences presentations, training webinars, and other dissemination resources to facilitate outreach and training.

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

Latest Updates

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


Subscribe to our newsletters....

Elrha © 2018 - 2022 Elrha is a registered charity in England and Wales (1177110). KEEP IN TOUCH Want to stay up to date with our latest updates? Sign up to our newsletters
Elrha Please upgrade your browser

You are seeing this because you are using a browser that is not supported. The Elrha website is built using modern technology and standards. We recommend upgrading your browser with one of the following to properly view our website:

Windows Mac

Please note that this is not an exhaustive list of browsers. We also do not intend to recommend a particular manufacturer's browser over another's; only to suggest upgrading to a browser version that is compliant with current standards to give you the best and most secure browsing experience.