In rural areas, the quality of the water bodies will continue to be influenced by the purification performances of small and smaller wastewater treatment plants (WWTPs). In this paper, the different methods of wastewater discharge and treatment currently available for rural areas were presented. Today, both technical and natural methods achieve purification results which are equivalent to, if less stable than those of larger technical pants, provided that dimensioning, design, and operation are optimally cared for. The general question will be to decide for a centralized wastewater system or for local, on-site solution installing small treatment plants. Important criteria for this decision as the distance between the houses and also crucial dimensioning parameters like the amount of wastewater will be given within the report. Several wastewater treatment technologies will be explained and also results from the SBR-System, which are applied in Germany special in smaller communities, are discussed. The evaluation of monitoring values showed that on average the required effluent qualities could be obtained. But still one has to consider that there are technical and economic limits of the degree to which WWTPs can be cared for in rural areas. For on-site treatment the main reasons is the organization of a good operation, maintenance and surveillance.
