Infiltration/inflow clear water

Unpolluted water, which is constantly found in public sewer systems. This water is of natural origin (spring catchment, groundwater drainage, ditches, flooding of systems or return/delivery pumping stations, etc), or artificial (fountains, drainage of buildings, cooling water, discharge from heat pump, water from air conditioning, etc). It has the disadvantage of diluting wastewater effluents and reducing the carrying capacity available in sewage systems and wastewater treatment plants.