The balancing tank is a storage unit that has the purpose of regulating the flow of rainwater discharged into the final receptor (public sewer, ditch, watercourse,…). This is in order to discharge a flow that does not exceed the limit specified by the regional and local governments and/or the water authority. The rainwater is fed to the gravity balancing tank through an inlet pipe and is discharged to the receptor through an outlet pipe located at the bottom of the tank. The diameter of the outlet pipe is such that the maximum discharge flow is never more than the permitted discharge to the receptor. In this manner, in the case of heavy rainfall, the water exceeding the permitted discharge rate is stored temporarily in the tank and released over a longer period of time. Balancing tanks are required in all those areas where high soil impermeability overloads stormwater sewerage systems, ditches or natural watercourses, thus creating rainwater disposal problems, above all during severe meteorological events. 

USE: Temporary storage of rainwater collected from an impermeable surface (roads, car parks, roofs, coverings in general, warehouses, pavements, etc.) during a meteorological event. 

REFERENCE REGULATIONS: Local regulations, for example: City of Trento: instructions for sizing balancing tanks – January 2011 Section 3 of Regional Decree 53 dated 27/01/2014, Marche Region