Reticulated sewerage systems Reticulated sewerage systems (network of pipes) carry sewage from homes to modern sewage treatment plants. Treated water from these plants is either reused or released into the environment. The pipes in your home are generally made of UPVC plastic or iron and the underground drains would probably be made of clay or UPVC plastic. These underground drains would lead to a reticulation sewer that carries the sewage to the nearest sewage treatment plant.
Tree roots are a major cause of sewer blockages. Fats become trapped amongst the roots and worsen the problem.	Tree roots breaking through the joint between two sections of sewer pipe.
Property connection onto a sewer upgraded with a PVC lining wound into place.	Brick sewer built in 1903.
Property connection onto a concrete sewer.	Cracked vitrified clay pipe.