Necessity and basis for establishment of European guidelines for reclaimed wastewater in the Mediterranean region

The use of reclaimed wastewater for irrigation contributes to water conservation and, therefore, is an important component of a sound policy for water resources management in the Mediterranean region. With the exception of France and Germany, European Mediterranean countries have not established guidelines for the use of reclaimed wastewater for irrigation. The existence of such guidelines means an important step in the planning and implementation of safe use of reclaimed wastewater for irrigation, because it contributes to a sustainable development of landscape and agricultural irrigation. Guidelines for reclaimed wastewater use for irrigation must clearly define what is allowed and what is forbidden to execute. This can be defined in great detail or in a broad manner, but must take into account some important specific local conditions, such as the quality of reclaimed wastewater, soil, climate, relevant crops and agricultural practices. Consequently, experimentation means a key-support to establishing guidelines. The experience from a research project with different type of reclaimed wastewater, crops and irrigation methods carried out for several years in the climatic Mediterranean region of Portugal brings some contribution to the technical content of possible European guidelines. Other aspects to be included in the proposed guidelines, such as monitoring and institutional management are also presented.