The Nosedo municipal WWTP is the biggest plant serving the city of Milan (Italy).
The Nosedo municipal WWTP serves the municipality of Milan. It purifies about 50% of the total urban sewage, corresponding to a treatment capacity 1,250,000 p.e. and an average flow of 5 m3/s.
Since the design stage of this plant, a great attention has been paid to some aspects of energy efficiency as, for example, choosing equipment with inverters, installing fine bubble aeration system with high efficiency in oxygen transfer and dO2 probes, to monitor and control the oxygen concentration in each biological treatment line.
It is also worth noticing that the WWTP of Nosedo has biological steps of oxidation – nitrification with high sludge age, tertiary treatments of sand filtration and high level disinfection.
In addition to this very good starting condition, in the year 2012 the company in charge of the plant’s operation & maintenance, Vettabbia S.c.a r.l. has started a virtuous process for improving energy efficiency.
A group of 7 concession companies has undertaken a Concession Contract with Milan Municipality, under which it had to build the plant in 1,340 days; funding 50% of the works; managing the plant for 16 years.
The complete plant was put into operation as from October 30, 2004 (3 months in advance).
Evidence of success
WWTP of Milano-Nosedo is one of the largest European water processing sites. It treats 50% of sewage of Milan, particularly those coming from the central and eastern area of the city- The WWTP is able to treat about 150,000,000 m3/year of wastewater which is then restituita to hydrografic system (Roggia Vettabbia) but also reused for irrigational purposes.
Potential for learning or transfer
The WWTP contribute to the purification of wastewater coming from a metropolitan area with around 1.300.000 showing that a solution for improving urban water management is feasible. The wastewater used to irrigate the rural areas is a precious resource for agriculture, also from the circular economy viewpoint. The WWTP is indeed a great example of reduction of water demand from conventional sources and efficient use of water resource, even across sectors.
The project also include other bettering of the surrounding areas aimed at recomposing the landscape and environmental features of part of the historical Vettabbia Valley, dominated by the Chiaravalle Abbey, and creating diverse yet interconnected habitats in order to maximise biodiversity.