Institutional portal - Municipality of Milan

All waste must be collected at the source and conducted to the public sewer channel through a pipe without interruptions of any kind along the route by gravity. If there are drain outlets located below road level, suitable devices must be adopted to avoid backflow. It is not permitted to channel waste into drains and rainwater collection grates, much less coming from other drains and/or grates.

In the case of buildings built after 1.4.1994 (date of approval of the Hygiene Regulations of the Municipality of Milan) or of new connections for buildings with purification facilities, separate networks must be provided for the different types of water to be removed ( meteoric, non-meteoric and process of production activities) distinctly up to the final delivery. If the street sewer pipe is single, unification upstream of the final delivery is permitted. Each net must have its own sample collection well with an opening of 40cm in diameter and a door of 50cm. In any case, the rainwater network must be equipped with a hydraulic siphon closure before unification with the non-rainwater network.

There must be a sufficient number of inspections on the pipeline to ensure maintenance and cleaning and equipped with suitable caps, corkscrews and gaskets.

The main pipe and the discharge columns must be extended (therefore with the same diameter of the column) beyond the last covering and be conveniently ventilated by means of towers of at least 40 cm if there are no windows in arrears and in the event that the last covering it is an unusable terrace or pitched roof. Otherwise the fumes must be carried beyond the ridge for pitched roofs with windows/dormers or towers of at least 2m when the last roof is a usable terrace.

The downspouts cannot act as vents for the private pipeline and therefore if there are previously authorized bathroom or kitchen drains (prior to 1.4.1994) they must be equipped with an vent and hydraulic siphon closure before the roof/gutter.

The horizontal pipe must be exposed underground. If this is not possible, the pipe must be placed in a special wall box that can be easily inspected, in order to allow for checks on possible leaks and maintenance.

The pipes must unify upstream of the interceptor siphon and the connection pipe must be made up of a 45° branch placed perpendicular to the municipal sewer system and in axis with the connection (bends are not permitted after the branch). No discharges are permitted between the Sifone and the Braga. The Braga is the inspection through which the Municipality of Milan, through the manager of the Integrated Water Service, carries out checks on the connection pipes such as unblocking operations or checks for possible breakages) and therefore must be placed in places that are always accessible and not on private properties.

Please remember that the internal sewerage network must be arranged under regular levels with joints and closures (inspections) with perfect hydraulic seal capable of resisting safely and without leaks, internal pressures of no less than 0,5 atmospheres.

FAQ SUE n. 89 - Published on October 12, 2021