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With the increased use, availability and implementation of Household Water Treatment and Safe Storage (HWTS) solutions in pre, active, and post-emergency contexts, humanitarian WASH practitioners face a multitude of options. There is currently no independent knowledge base or comprehensive analysis on HWTS options, implementation approaches, location and conditions of implementation, and their suitability for emergency contexts or their place in the emergency-development continuum. This is the gap that our innovation is targeting.

CAWST’s innovation complements existing initiatives by providing a dynamic, regularly updated space with expert moderated knowledge. It is the first space to use visual geo-mapping of information.


CAWST is creating a centralized, web-based, knowledge and technical support hub on Household Water Treatment and Safe Storage (HWTS) solutions to support WASH practitioners, including those working in pre, active and post-emergency settings. This innovation will improve existing humanitarian practice:

  • By making relevant information available, it will allow humanitarian WASH practitioners to increase their decision making efficiency and effectiveness in implementing quality, contextually appropriate and timely WASH solutions.
  • By creating an online platform with structured information, active content management and expert moderators, WASH practitioners will be able to easily access a tool with credible and up-to date information, providing a positive user experience. This will encourage more practitioners to share their knowledge on HWTS solutions and implementation, learn what has/has not worked for others, incorporate it into their decision making and project implementation and adapt their HWTS implementation accordingly, resulting in better emergency decisions and responses.


This project will provide a user-friendly, interactive, online knowledge base where Household Water Treatment and Safe Storage (HWTS) implementers and practitioners can access information, connect, and contribute their experiences. Practitioners worldwide will access the knowledge base and learn about the latest available products, implementation models, and successes and failures of HWTS projects. They will also connect and interact with others working in similar regions/technology contexts.

This increased level of knowledge and stronger network amongst HWTS implementers will support practitioners to plan and deliver more successful HWTS projects that incorporate appropriate technology choices, tried and tested implementation models, and shared learnings. Improved HWTS implementation will lead to a higher rate of correct, consistent and continued use of HWTS products by vulnerable communities, improving their health.

This innovation will bring incremental change to significantly improve WASH implementation and coordination among key actors in humanitarian WASH response before, during and after emergencies.

Latest Updates

Household water treatment and safe storage knowledge base

10 Jan 2017

This readily available information hub on contextually appropriate technologies and approaches will serve as a key resource for emergency response and recovery efforts in affected populations.


Providing safe water in emergencies: context is king

23 Nov 2017

CAWST have made progress on the accessibility of the Knowledge Base and increased the availability of context-specific information through the launch of the HWTS Knowledge Base mobile app and Country Focus pages


Helping wash practitioners get the HWTS knowledge they need, for their specific context

28 Aug 2018

In this second phase, CAWST have created a central place online where emergency response practitioners can access high quality, verified information on HWTS.


Read HIF Emergency Household Water Filter Challenge: Evaluation Matrix And Report

Using filter performance criteria developed by the HIF, CAWST interviewed a range of experts to reach average ‘importance weightings’ of factors such as efficacy, logistics and cost for filter performance in five hypothetical emergency scenarios.

Read now

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