Safe water is essential for protecting public health during humanitarian emergencies. Waterborne diseases like cholera and Hepatitis E are some of the leading causes of preventable illness in refugee and displacement camps around the world.

Treating water with chlorine is a safe and effective way to destroy harmful pathogens and protect it from recontamination. But in humanitarian settings knowing how much chlorine is needed for a specific site is challenging. In many places, applying the common guidance simply isn't sufficient to ensure water is protected for long enough to prevent waterborne diseases.

The answer isn't just to add more chlorine because the taste and smell can be off-putting for some people. What's needed is an easy way to provide reliable, site-specific guidance for chlorine treatment that takes account of these issues.

The SWOT works with the water quality monitoring data you already collect, and you can get started with the equipment and staff you already use. To get a reliable recommendation you need to provide around 150 paired samples, each with a measure of free residual chlorine taken at the tapstand and again at the household. This data can be collected for a site as a specific exercise carried out every few months, or as an ongoing process.

We have monitoring tools, templates, and detailed instructions available as well as a support desk if you need more in-depth advice. We have experience supporting teams working with online and bulk chlorination of piped water networks, as well as in contexts with water trucking and handpump chlorinators.

Whatever your use case, we are here to support you to get the most out of the SWOT.

The SWOT applies novel machine-learning and numerical modelling tools to the problem of post-distribution chlorine decay modelling. These modelling tools come from years of water safety research in refugee camps in South Sudan, Jordan, Rwanda, Tanzania, Bangladesh (and elsewhere) by our team at York University, the University of California, Berkeley, and field partners at MSF and UNHCR.

Because the models are based on real, site specific, monitoring data they account for all the factors that affect the rate of chlorine decay, from water temperature to handling practices and the type of storage containers being used.

After the analysis is completed, the SWOT provides clear results that can be applied directly and immediately to modify water treatment parameters and improve safety of water at the household level. In addition to the target recommendation, the analysis provides a summary of the current water safety at the site, and a predicted improvement that would be possible by implementing the SWOT recommendation.

This information is critical for deciding what action is needed to improve water safety at the sites you manage. This could mean increasing free chlorine residual at the tapstand, rolling out a jerrycan cleaning campaign or slowing chlorine decay through better water storage.

Based on your site-specific needs we can help you identify the most appropriate measures to improve water safety.