发展中国家水处理厂的设计应反映当前的社会、经济和技术条件。在发达国家，一个简单的核电站比一个复制的核电站更有可能在数年内保持可操作性。以下技术说明了适合发展中国家社区的治疗类型:预处理；化学制品；化学给料机；液压快速搅拌机；水力絮凝器；水平流沉淀池；过滤器间灰化过滤装置；直接过滤；上流-下流过滤器；慢砂滤池；和过滤器间洗涤下降率过滤器。在可行的情况下，本土材料也更合适。例如，如果当地没有明矾，凝固剂和助凝剂可以从节肢动物的种子或外骨骼中提取。 包括7个参考文献、表格、图表。

The design of water treatment plants for developing countries should reflect the prevailing social, economic, and technical conditions. A simple plant is far more likely to remain operable over a period of years than a duplicate of a plant in a developed country. The following technologies, illustrative of the kinds of treatment appropriate for communities in developing countries, are discussed: pretreatment; chemicals; chemical feeders; hydraulic rapid mixers; hydraulic flocculators; horizontal-flow settling basins; interfilterwashing filtration units; direct filtration; upflow-downflow filters; slow sand filters; and interfilter-washing declining-rate filters. Indigenous materials are also more suitable where feasible. For example, coagulants and coagulant aids can be derived from seeds or the exoskeletons of arthropods if alum is not locally available. Includes 7 references, table, figures.