Part of a waste management system, the actual sewage pipes aren't accessed but rather the maintenance tunnels that are explored. These tunnels are sectioned off by valve-controlled gates, which require a team of two to operate. There are at least 13 different gate systems, though few are actually operable. The tunnels are constructed around three key features of the sewage system - a bilge tank, a spillway, and a large, main drain chamber. How far the sewer system continues outside of Shepherd's Glen is unknown, as access to the deeper sections of the underground complex is either cut off, or simply left unexplored.