Bio-sand filters: Cheap technology to purify water
THE Centre for Affordable Water and Sanitation Technology (CAWST) has embarked on massive training of Ugandans to ensure that they get clean water.
By Juliet Waiswa
and Gladys Kalibala
THE Centre for Affordable Water and Sanitation Technology (CAWST) has embarked on massive training of Ugandans to ensure that they get clean water.
CAWST, in collaboration with Rotary Club of Calgary in Canada, trained representatives from army, the Police and students from institutions to construct bio-sand filters, which kill bacteria in water. CAWST is working with Rotary Club to raise awareness on global water issues.
The Rotary Club of Muyenga invited a technical advisor, Tal Woolsey, to train 42 Ugandans on how to construct the filters.
The director of Connect Africa, Trevor Tychon, linked the Muyenga Club to CAWST and facilitated the training at his residence in Muyenga.
A bio-sand filter is one of the community-driven initiatives that CAWST has come up with to ensure that people, especially in rural areas, get safe drinking water.
Constructing a filter involves mixing cement with stones, water and river sand. The mixture is then poured into a metric quadrilateral-shaped mould and the mould left to dry.
Tychon says quarry stones of varying sizes are placed at the bottom of the bio-sand filter. They are mixed with water and sand and left to settle. After an hour, the water is ready for drinking.
When the water is poured into the filter, the diffusion plate reduces the force of the water. The water goes to the bio-sand and after passing through the gravel stones, it is propelled up and down and poured into a bucket.
It removes 98% bacteria and the 2% can be disposed of by putting the water in a plastic container and leaving it under the sun. The locally-made filters cost sh30,000.
The system has been adopted internationally. According to a 2006 report, Centre For Water and Sanitation, CASWST has empowered people in Angola, Bangladesh, Bolivia, Cambodia, Guinea, Kenya, Laos, Mexico, Sri Lanka and Zambia, with skills to purify their drinking water.
and Gladys Kalibala
THE Centre for Affordable Water and Sanitation Technology (CAWST) has embarked on massive training of Ugandans to ensure that they get clean water.
CAWST, in collaboration with Rotary Club of Calgary in Canada, trained representatives from army, the Police and students from institutions to construct bio-sand filters, which kill bacteria in water. CAWST is working with Rotary Club to raise awareness on global water issues.
The Rotary Club of Muyenga invited a technical advisor, Tal Woolsey, to train 42 Ugandans on how to construct the filters.
The director of Connect Africa, Trevor Tychon, linked the Muyenga Club to CAWST and facilitated the training at his residence in Muyenga.
A bio-sand filter is one of the community-driven initiatives that CAWST has come up with to ensure that people, especially in rural areas, get safe drinking water.
Constructing a filter involves mixing cement with stones, water and river sand. The mixture is then poured into a metric quadrilateral-shaped mould and the mould left to dry.
Tychon says quarry stones of varying sizes are placed at the bottom of the bio-sand filter. They are mixed with water and sand and left to settle. After an hour, the water is ready for drinking.
When the water is poured into the filter, the diffusion plate reduces the force of the water. The water goes to the bio-sand and after passing through the gravel stones, it is propelled up and down and poured into a bucket.
It removes 98% bacteria and the 2% can be disposed of by putting the water in a plastic container and leaving it under the sun. The locally-made filters cost sh30,000.
The system has been adopted internationally. According to a 2006 report, Centre For Water and Sanitation, CASWST has empowered people in Angola, Bangladesh, Bolivia, Cambodia, Guinea, Kenya, Laos, Mexico, Sri Lanka and Zambia, with skills to purify their drinking water.