Ceramic Silver Pot (CSP) filter

CSP filter (Ceramic Silver impregnated Pot model). 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.