Tanzanian engineer invents low-cost water filter

Dr. Askwar Hilonga is a Tanzanian scientist who has created a water filter that he says can remove 99.9 percent of bacteria, micro-organisms and viruses.

The invention uses nanotechnology to filter out contaminants and produce clean water.

The idea was inspired by a visit to his parents’ village outside Arusha in Tanzania, where many people still risk their lives drinking dirty water and often suffer from water-borne diseases.

Catherine Nanyaro is a housewife and lives in Arusha. She says the filter has also helped her save time as she goes about her chores.

“Before I had this filter, I used to fetch water from the river, and sometimes I used it without boiling it because it is very time consuming to boil the water. I had many problems, like typhoid, and other diseases from the water,” she said.

The filter can be tailored to absorb anything from copper and fluoride to bacteria and viruses. Gravity pulls the water down through a series of buckets connected by tubes. The buckets contain sand with a layer of ‘good’ bacteria on the top, which eat the microbes that contain diseases like Typhoid.

The magnetic quality of the sand also kills other bacteria as the water filters through it.

The final bucket uses nanomaterials to filter out any remaining microbes. In short, an invisible biological ‘net’ which stops bacteria from passing through, but allows the water to reach the final bucket bacteria free.

Dr. Hilonga was one of only four students in his year to graduate from primary school. He went on to university and won a scholarship to study a PhD in nanotechnology in South Korea.

When he returned home, he started looking for ways to use his expertise to help people.

“In Tanzania, 70 percent of households, of nine million households, are not using any kind of a filter. That is how big the market is. That is in Tanzania alone, nine million households. Now imagine in Kenya, Uganda, Ethiopia, sub-Saharan Africa, India and elsewhere. So the market is very big,” Dr. Hilonga explained.

One filter is capable of supplying many litres of clean water a day.

The Blue Sky primary school in Arusha uses it to quench the thirst of more than 70 children.

“We analysed the water around, and we have a river like 50 metres far from here, and we saw that it is not healthy, that water. Then we took water from the government supply, but we also saw that it was not going to be healthy and we want the best things for our kids, so we decided to buy the filter,” said Blue Sky primary school headteacher, Elena Ramos.

Dr. Hilonga has received a grant from the U.S. government to help him make his filter available commercially. One filter costs about 140 U.S. dollars.

He hopes the filter will one day be used to help communities and villages across Africa access clean water.