Ceramic Silver Pot (CSP) filter

Family using a CSP (Ceramic Silver impregnated Pot model) filter in Zapatera, Nicaragua. Photo: NWP.

A new alternative to conventional ceramic candle filters is the CSP filter.This model has a pot-shaped ceramic filtering element that is treated with colloidal silver. It has a bigger capacity and is easier to produce locally than candle filters. Also leakages are easier to detect than in candle filters so there is less risk in use.

Evaluations, including a USAID-funded test in Nicaragua, indicate that CSP filters remove turbidity and harmful bacteria that cause diarrhoea, cholera and other waterborne diseases.Maintenance consists of cleaning with a brush and changing the ceramic element every 2-3 years. If filled twice a day the filter produces enough for a family of six.

Field studies have shown that investment in a filter is “paid back”within 3 to 6 months because of savings on expenses for medicines, fuel wood and labour. In Nicaragua, Guatemala and Cambodia the production of this filter is a commercial activity and production is starting up in six other countries.

“A filter for family use that provides clean and bacteria-free water at a cost of US$ 3-5 per family per year” - Ron Rivera of the NGO Potters for Peace.

Construction, operations and maintenance

Capacity: 10-20 litres/day.

Costs

Cost complete filter: (off-factory): US$ 8 in Cambodia, US$ 10-15 in Nicaragua.

Cost of introduction: US$ 15,000 - 30,000 for project incl. training, machinery and a first production of 500 filters. US$ 50,000 - 100,000 for project incl. production shop, training, first promotion, and 5,000 filters.

Field experiences

150,000 in Central America, Asia and Africa.

Acknowledgements

• SmartWater Solutions: Examples of innovative, low-cost technologies for wells, pumps, storage, irrigation and water treatment. or (alternative link). Netherlands Water Partnership, 2006.