Using sunlight to purify water in Vietnam

Many infants in Vietnam die of diarrhoeal diseases, while older children and adults also suffer from them. The main cause is contaminated drinking water. And yet there is a very simple method for ridding water of germs – and it uses sunlight. HELVETAS Swiss Intercooperation showed local people how this works.
The project was successfully completed in 2015.
Over 70 percent of the rural population in Vietnam has to drink water that does not satisfy even basic standards of hygiene. Vietnam’s government has set itself the goal of ensuring that the entire population has access to clean piped water by 2020.

The people suffer greatly due to contaminated water. During the rainy season, large parts of the country are flooded for months at a time. Local people have adapted to this. They build their houses on stilts or hills, and many live on boats. Yet the scope for boiling water adequately to kill the germs are limited.

HELVETAS Swiss Intercooperation introduced therefore the SODIS water disinfection method to Vietnam. This is a simple and scientifically proven technique for disinfecting drinking water at home. Contaminated water is put in transparent PET or glass bottles, which are then left in the sun for at least six hours. During this time, UV radiation from the sun kills the germs in the water.

This technique can be used anywhere, which is why the SODIS method is ideal for improving people’s health and quality of life in remote regions.

HELVETAS Swiss Intercooperation offered training and assistance to local people to raise awareness about this simple and efficient method. Lectures in schools were particularly effective, as children quickly share their newly acquired knowledge with their families. This ensured that the benefits from SODIS are spread rapidly to many Vietnamese men and women.
Vo Ket
image description When an expert told us about SODIS I was amazed and I thought, “If this really works, it’s fantastic.” And it does work! SODIS and hygiene education have changed our lives for the better. image description Vo Ket, who lives in Village No 4 in Long An province


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