Revitalization of an artificially recharged groundwater source: Mediana in the city of Niš, Serbia

The artificially recharged groundwater source Mediana provides water supply to the City of Niš. It is situated on some 250 ha of land in an alluvial valley. In the early 1990s, the source sustained heavy pollution by organic pollutants from nearby electronics industry, and somewhat less extensive pollution by nitrites from a neighbouring settlement. The capacity of the source decreased from 270 l/s to 150 l/s. The pollutants were flushed and a permanent protection system was put in place. Following revitalization, this groundwater source was upgraded to the current capacity of 500–600 l/s. Monitoring of the groundwater source during the period from 1996 to 2006 revealed no functional interferences, confirmed that the source delivers the required water quality, and indicated that significant self-purification processes are taking place in the aquifer.