Dirty wastewater contains bacteria and harmful nutrients that affect the quality of surface and groundwater as well as our coastal waters. A modern household includes a well-functioning sewer system that meets statutory requirements. A cesspool (holding tank) does not purify wastewater from bacteria and harmful nutrients but collects thicker sludge. According to legislation, your property can be located in a network area for a public sewer system or in an area outside the network area, which determines whether you should connect your property to a public sewer network or whether you should have your own sewage wastewater treatment system.