Houshold Water Treatment in Developing Countries: Ceramic Filtration
Household water treatment and safe storage (HWTS) interventions are proven to improve water quality and reduce diarrheal disease incidence in developing countries. Five of these proven HWTS options – chlorination, solar disinfection, ceramic filtration, slow sand filtration, and flocculation/disinfection – are widely implemented in developing countries. Organizations wanting to develop HWTS programs are often faced with the difficult decision of selecting which option or options are appropriate for their particular circumstances. The most appropriate HWTS option for a location depends on existing water and sanitation conditions, water quality, cultural acceptability, implementation feasibility, availability of HWTS technologies, and other local conditions. This series of fact sheets is designed to assist organizations in comparing, and ultimately selecting, the appropriate proven HWTS option or options. For more information on household water treatment, please visit www.who.int/household_water. For more information on ceramic filtration programs in developing countries, please visit www.pottersforpeace.org.
Table of Contents
Ceramic Filtration
Locally manufactured ceramic filters have traditionally been used throughout the world to treat household water. Currently, the most widely implemented HWTS ceramic filter is the Potters for Peace design, which is flowerpot shaped, holds about 8-10 liters of water, and sits inside a plastic or ceramic receptacle. The filters are produced locally at ceramics facilities, and then impregnated with colloidal silver to ensure complete removal of bacteria in treated water and to prevent growth of bacteria within the filter itself. Numerous other locally-made and commercial HWTS ceramic filters are widely available in developed and developing countries.
Most ceramic filter HWTS systems are based on a filter/receptacle model. To use the ceramic filters, families fill the top receptacle or the ceramic filter itself with water, which flows through the ceramic filter or filters into a storage receptacle. The treated water is then accessed via a spigot embedded within the water storage receptacle.
The Potters for Peace filter, locally produced in Nicaragua
(CDC / D. Lantagne)
Lab Effectiveness, Field Effectiveness, and Health Impact
The effectiveness of ceramic filters at removing bacteria, viruses, and protozoa depends on the production quality of the ceramic filter. Most ceramic filters are effective at removing most of the larger protozoal and bacterial organisms, but not at removing the smaller viral organisms. Studies have shown removal of bacterial pathogens in water filtered through high quality locally-produced and imported ceramic filters in developing countries. A 60-70% reduction in diarrheal disease incidence has been documented in users of these filters. Studies have also shown significant bacterial contamination when poor-quality locally produced filters are used, or the receptacle is contaminated at the household level. Because of the lack of residual protection, it is important that users be trained to properly care for and maintain the ceramic filter and receptacle.
Benefits, Drawbacks, and Appropriateness
The benefits of ceramic filtration
- Proven reduction of bacteria and protozoa in water;
- Acceptability to users because of the simplicity of use;
- Proven reduction of diarrheal disease incidence in users;
- Long life if the filter remains unbroken; and,
- A low one-time cost.
The drawbacks of ceramic filtration are:
- Lower effectiveness against viruses;
- Lack of residual protection can lead to recontamination if treated water is stored unsafely;
- Variability in quality control of locally produced filters;
- Filter breakage over time, and need for spare parts;
- Filters and receptacles need to be regularly cleanes, especially when using turbid source waters; and,
- A low flow rate of 1-3 liters per hour in non-turbid waters.
Ceramic filtration is most appropriate in areas where there is capacity for quality ceramics filter production, a distribution network for replacement of broken parts, and user training on how to correctly maintain and use the filter.
Resources
The issues in this article are addressed on the USAID Environmental Health web pages. For more topics relating to environmental health, visit the web site at: http://www.ehproject.org
Related Pages
Household Water Treatment Options in Developing Countries Fact Sheets
- Ceramic Filtration
- Flocculant/Disinfectant Powder
- Household Chlorination
- Safe Water System
- Solar Disinfection (SODIS)
- Proven Household Water Treatment Options
- Interventions to Reduce Diarrheal Disease
Preventing Diarrhea in Developing Countries - Country Fact Sheets
- The CDC/PSI Project in Kenya
- The Jolivert Safe Water for Families Project in Rural Haiti
- The CDC/PSI Program in Zambia
Household Water Treatment Articles
- Boiling: Household Water Treatment Options in Developing Countries.
- Filtration & Chlorination Systems: Household Water Treatment Options in Developing Countries.
- Preventing Diarrheal Disease in Developing Countries
- Simple Options to Remove Turbidity
- Safe Storage of Drinking Water
Household Water Treatment Technical Reports
- Working with local health care staff to increase SWS uptake
- Safe Drinking Water and Hygiene in Kenyan Schools
- Effect of Chlorination on Inactivating Selected Pathogens
- Chlorine Residual Testing
- Preventing Diarrhea in Persons Living with HIV and AIDS
Household Water Treatment Manuals
Safe Water for the Community: A Guide for Establishing a Community-Based Safe Water System Program
Household Water Treatment
