Impact Journalism Day 2016 |

Making Light Work of Dirty Water

A near-death experience inspired Martin Wesian to devise a low-cost UV solution that makes water drinkable.

Alfred Tumushabe
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A woman drawing water from a rainwater harvesting tank.
A woman drawing water from a rainwater harvesting tank.Credit: Alfred Tumushabe
Alfred Tumushabe

Stella Kyomuhangi is a mother of eight young children. She lives with her husband, Bedius Aruho, in Mbarara District, southwest Uganda. Like many other places in the district, the area doesn’t have a lot of bushes or shrubs. This poses a challenge when sourcing firewood – the only means of energy for cooking in homes and boiling water.

Realizing that lack of safe water was a serious challenge for the community, an international nongovernmental organization, Agency for Cooperation and Research in Development (ACORD), started a project to build tanks for the harvesting of rainwater. The sources of water were streams, swamps and communal wells.

Although water tanks lessened the challenge of providing water for household use, they didn’t curtail the unhealthy culture of drinking unboiled water. People were still drinking unclean water from the tanks, just as they did the water that came from streams and wells. According to the residents, this was due to the lack of firewood. As a result, children would often suffer diarrhea and other diseases.

“It’s not that we didn’t know about the dangers of drinking unboiled water, but the challenge was the lack of firewood,” relates Kyomuhangi. ACORD had to find a way of sanitizing the water without first having to boil it. This is how the WADI water disinfection device reached the rural community last September.

A creation of Australian company Helioz, WADI is an ultraviolet (UV) measurement device. The equipment is the size and shape of a small pocket radio or voice recorder. The ultraviolet radiation from the sun renders harmful pathogens in the water inactive and, over time, this makes the treated water safe to drink.

The WADI.Credit: Alfred Tumushabe

Ironically, the Ugandans owe their improved health to the near-death experience of Helioz founder Martin Wesian, who had contacted cholera while in Venezuela. This set him on the road to creating an easy-to-use, inexpensive household water treatment solution for the poor, who have no access to this basic human utility. “Because of cholera, I lost 15 kilograms in 10 days and I saw people die around me,” recalls Wesian.

Even with all our modern technological advancements, the majority of the world’s population still dies from lack of access to safe water. Helioz is currently focusing on six countries – Uganda, Ethiopia, Kenya, India, Nepal and Pakistan – to bring safe water to communities through NGOs like ACORD.

How the WADI works

In order to disinfect the water, it is poured into a PET (polyethylene terephthalate) bottle – the common, colorless plastic used to package processed water. The bottle is then placed on a rack or table and exposed to sunlight. The WADI (Water Disinfection) device is then placed beside the bottles (there can be as many as 20 or more bottles).

The WADI device then helps gauge whether the water has been disinfected by the sunlight. The device has a small screen showing “power bars” that keep materializing (like a phone battery charging). Once four bars have appeared, it means the water in the bottles has been disinfected. The water to be treated needs to be clear and without chemical contamination from the likes of lead and manganese; UV only kills biological contaminations such as bacteria, protozoa and, to a lesser extent, viruses.

Users also keep observing the small, in-built animation on the device screen, which they have nicknamed kakyebezi (checker). When a smiley face appears, it means the water is ready for drinking. It takes between three to six hours for the sun-kissed water to become safe.

Ultraviolet disinfects water from boreholes and springs (but only those in villages), and from gravity flow systems and rainwater collected in tanks or containers. This is because this water is largely free of chemical contamination. The disinfected water has to be stored in clean containers and consumed within two days.

“For the four months I have been using the WADI, my children no longer suffer from illnesses. I make sure I treat at least seven liters of water each day for the whole family,” says Kyomuhangi, adding, “The children take some to drink at school.”

Following initial training (by ACORD) on how to use and maintain the device, she says she hasn’t encountered any problems with it.

Reading time for the kids

The device has also helped in less obvious areas. “The children now have time to read. They had been spending a lot of time looking for firewood to boil water,” says another resident. “Besides, this water tastes good, unlike the one we boil – which sometimes has a bad odor.”

“I treat five liters of water daily for us to drink,” says another local resident, Adrine Nuwagaba. “The neighbors who don’t have the WADI bring their water here for disinfecting. Lack of firewood is a big problem here; it has been difficult for us to boil water. We have been taking it the way you get it from the tank,” adds Nuwagaba.

Dunstan Ddamulira, ACORD’s programs manager in Mbarara District, says they previously piloted the use of UV light to treat water in Kisoro District, further west. However, although they exposed bottled water to sunlight for many hours, they didn’t have a mechanism to ascertain whether it had been disinfected or not.

The WADI device costs 52,000 Ugandan shillings ($15), but it’s not currently available on the local market; it can only be imported from Australia. It runs on solar energy so doesn’t need any other power source. The device is lightweight and water-resistant, has a two-year warranty and is environmentally friendly.

Some 500 homes are currently using WADI devices in various parts of Uganda. ACORD has also launched a two-year drive to reach a further 74 schools and 500 households in the East African state.

ACORD also hopes the popularity of the life-saving innovation will grow, and will encourage businessmen to import the devices into Uganda, so they’re easily accessed by individuals and institutions.

This article first appeared in Ugandan newspaper The Daily Monitor.

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