Wastewater treatment is particularly important to maintain a clean and healthy living environment. Through wastewater understood in this context, the dirty water from household activities, industry, public institutions or to other uses, i.e. waters whose characteristics have been changed after using. Stormwater too, under certain conditions, will not be considered conventional clean water and will be subject to treatment prior to its infiltration into the ground or discharge a receiving water. Protecting existing water resources requires quality and quantity controlling of discharges both high flow and low flow rates. Small wastewater flows, seemingly insignificant, produce little local pollution, which must be removed before they can grow. If big cities already have modem sewage treatment plants with a treatment technology well developed, small consumers raises specific issues. Therefore it is not possible direct application of treatment technologies by simply sizing for smaller capacities. In this paper the authors present some aspects of wastewater treatment from small households or from other consumers, which in terms of discharge water quality can be compared with those.
