Treatment
As provider of the Integrated Water Service, Metropolitana Milanese coordinates and controls the water treatment system for the City of Milan. This system is structured in three industrial treatment centres, each one run by a different contractor, under the agreements signed by the Milan Municipality. The water treatment service in the City became fully operational in 2005 and can serve a total of up to 2,550,000 population equivalent (PE - A conventional unit of wastewater treatment load.) .
The quantity of wastewater treated by the plants has not changed much over the recent years.
The total quantity processed by the wastewater treatment plants exceeds the water delivered by the waterworks, since the wastewater system collects both sewage and drained part of the rainfall.
| TREATMENT SERVICE – CITY OF MILAN | |||
| PLANT | CONTRACTOR | RESPONSIBILITIES OF CONTRACTOR | RESPONSIBILITIES OF MM |
| Milano San Rocco | Degrémont Spa | Contract management of the plant
In-house controls of treatment efficiency |
Control of correct functioning of plant and verification of contract management terms |
| Milano Nosedo | MilanoDepur Spa | Contract construction and management of the plant In-house controls of treatment efficiency |
Control of correct functioning of plant and verification of contract management terms
Transport and disposal of treatment sludge and residue |
| Peschiera Borromeo (2° linea) |
Amiacque Srl | Treatment serving the eastern Milan suburbs | Administrative control |
| CHARACTERISTICS OF THE TREATMENT PLANTS | |||
| PLANT | MILAN SAN ROCCO | MILAN NOSEDO | PESCHIERA BORROMEO (LINE 2) |
| Basin | West+Municipality of Settimo Milanese | Centre-East | East |
| Year of commissioning | 2004 | 2003-2005 | 2005 |
| Size of basin served | 101,3 km2 | 69 km2 | 22,3 km2 |
| Maximum population served (in PE) | 1.050.000 | 1.250.000 | 250.000 |
| Design capacity | 4 m3/s | 5 m3/s | 1,10 m3/s |
| Modifications
2005 – 2008
(undertaken by contractor) |
Sludge drying | Sludge drying | |
The Milan San Rocco and Milan Nosedo plants form the backbone of the Milan wastewater treatment system, while the third (ie, the treatment line 2 at Peschiera Borromeo, serving the eastern Milan suburbs) became necessary for technical and hydraulic reasons since the served area, except the northernmost section, is basically disconnected from the city sewage system by two large barriers – the railway belt and the northern Lambro river.