Foul water drainage is installed underground and is required to carry waste-water from appliances in bathrooms, kitchens or utility rooms away from the building. For properties connected to the mains drainage, the foul water drainage system will connect to the main sewer which will then transport the waste water to a local treatment plant, or remote properties not connected to the mains sewer, the foul water drainage pipes will need to connect to a sewage treatment plant on the property or a septic tank. Various types of materials are used for foul drainage. The most common type of material used for smaller sizes is plastic which benefits from being quicker to install and cheaper. Other materials used include clay which is more common for medium sized pipes and concrete which is typically used on larger installations. All drainage system incorporate manholes or inspection chambers.