The project concerns a sampling program at the most important Wastewater Treatment Plants in the North Aegean Region, which aims to control the quality or characterise the quality of waste water. The ESAs in which the programme will be implemented are the eleven (11) existing SPDs of priority settlements B and C in accordance with European Directive 91/271/EEC, namely one (1) in Limnos, one (1) in Chios, five (5) in Lesvos and four (4) in Samos.The above units will be sampled and analysed to monitor the quality of treated wastewater, in accordance with the requirements of the existing legislation (CYP). 5673/400/14-3-1997, OJ 192B).