Slow sand filtration for community water supply : planning, design, construction, operation and maintenance

Established information on slow sand filtration is presented, as well as guidelines resulting from demonstration projects in develping countries. The basic principles of community water supply and community participation are set out before entering into a detailed discussion on the slow sand filtration process. Overall system design and the cost of construction, operation and maintenance are discussed. To illustrate the previous information, an example of planning and designing a slow sand filtration system for a hypothetical community is given. This is followed by detailed information on the structural design, which is further illustrated by design examples. It should be understood, however, that these examples are based on specififc local conditions and may not be applicable under other circumstances. Because the quality of construction can greatly be improved in many cases, construction guidelines are also presented. Finally, outlines are given for detailed operation and maintenance procedures and the importance of proper training is emphasized. There are appendices on pre-treatment, chlorination, soil investigation, flow measurement and water quality analysis.