For years, the southern basin of Lake Ceresio has been experiencing a deterioration in the quality of the water connected to the contribution coming from the sewerage networks of coastal towns bordering the lake, which creates a situation of compromised lake environment with important consequences both on the use by the local Italian and Swiss populations and on the image of the territory and on the attractiveness of the lake from the tourist point of view. The studies carried out by the International Commission for the Protection of Italian-Swiss Waters (CIPAIS) have identified discharges from the sewerage networks of the Municipalities on Italian territory as the main cause of the poor state of the basin waters. The ACQuA Ceresio project aims to improve the quality of the waters of Lake Ceresio by intervening on the sewage and purification system and making it more efficient.