Lacks and needs of R&D on wastewater treatment in small populations

Wastewater treatment in small communities, with less of 2,000 population equivalent, is one of the priorities of the new Spanish National Plan for Water Quality: Sanitation and Purification (2007-2015). Due to the peculiarities of the small agglomerations, the treatment solutions used in medium and large cities usually do not give satisfactory results if they are implanted directly into those communities. It is therefore necessary to adapt these technologies to the small towns or to search for new treatment solutions. In this regard, R&D activities play a key role. In fact, many research groups address their activities to the study of sanitation and treatment of small populations. In relation to the technologies studied there is a wide range that includes both extensive and intensive technologies. In the case of Spain, as in other countries, constructed wetlands seem to be the most studied technology in the recent years to sewage treatment in small settlements. However, there are still areas of study to be promoted in order to solve the current problems of sanitation and wastewater treatment in small settlements.