skyline of the city of Milan
The sewer system and wastewater treatment

MM manages wastewater, from the collection of the wastewater from the houses and industries, to its collection in the main sewers and treatment of the wastewater coming from the municipal district of Milan.

MM also handles the network of drains of the city’s watercourses. At present the network consists of over 1,500 km of piping with a service coverage of over 98%. Limited isolated parts of the municipal district outside the urban area remain excluded as do some production plants equipped with independent wastewater treatment systems. A quantity of about 290 million cubic metres of wastewater from the district of the municipalities of Milan and Settimo Milanese flows into the sewer system.

The wastewater is then transferred to the treatment system, which is divided into three plants:

•    Milano San Rocco
•    Milano Nosedo
•    Peschiera Borromeo

The Milano San Rocco and Milano Nosedo plants constitute the main structure of the wastewater treatment system of Milan, while the Peschiera Borromeo plant, understood as the 2nd line of treatment serving the eastern area of Milan, had to be constructed to meet technical and hydraulic requirements.

In particular, the catchment area served, except for the northernmost part, is substantially disconnected from the rest of the city’s sewer system due to two major barriers represented by the railway belt and the Northern Lambro river.