Gravit’eau: washing hands with recycled water

Terre des hommes and partners (Swiss Solidarity, eawag, FHNW, Graviteau Association and Humanitarian Innovation Fund) are deploying a mobile hand-washing station which uses an automatic water recycling system to deal with water shortages in crisis situations.

Deployed in the context of a pilot project in a camp for displaced persons in Nigeria, this innovative idea has enabled more than 400 children to wash their hands each day, reducing the spread of disease and epidemics. It is replicated in other contexts where there is a limited access to sanitation infrastructure such as healthcare centres, schools and refugee camps.


Did you say Gravit’eau?


Gravit’eau is a system used in mobile hand-washing stations which use a very small amount of water thanks to a self-regenerating system. Ideal for water-scarce and crisis settings, Gravit’eau safely reduces water use by up to 99% per handwash when compared to other methods. Waste water is collected in a tank and then automatically filtered by a membrane. The system works by gravity. The technology enables water to be recycled without the use of electricity, without any complex maintenance and without a continuous supply of chemical products. The filtration membrane is so fine that it does not let bacteria or viruses pass through. Water for washing hands flows by means of a foot pump.


Washing hands reduces 50% of cases of diarrhoea and pneumonia among young children and restricts to a great extent the spread of infectious diseases and epidemics such as cholera and Ebola. Gravit’eau was developed to be a simple to use solution”, explains Bruno Pascual, our expert in water, sanitation and hygiene in emergency situations.


A pilot phase in a camp for displaced persons


Gravit’eau pilot projects currently target the most vulnerable populations in refugee and internally displaced person camps, primary health care facilities and schools in Nigeria, Mali, Burkina Faso and Palestine that do not have functional water supply systems.


Up to 100 children an hour can wash their hands using an average of just 2 ml of water per wash. The water in each station only needs to be changed once a month. Stations require very little maintenance, which is a real plus in this type of context.


Impact and potential


If there is anything that the COVID-19 pandemic has reinforced, it is that increasing access to safe, sustainable sanitation is more important than ever with a constant concern for technical improvement. To ensure that good practices are employed, we educate and instruct users on the benefits and process of such an approach. Moving beyond hand washing, other uses of this filtration technology are being investigated involving larger amounts of water, particularly for processing domestic waste water used for cooking or for personal hygiene.


With the support of