A series of sewage pipes and support structures underneath the City of Tears. At the east end is a lift shaft to the City that has been destroyed. Near the northeast end is a shaft connecting to Eternal Emilitia's room in the City of Tears.
| Defender's Crest |
requires defeating Dung Defender
| Flukenest |
requires defeating Flukemarm
| Mask Shard x 1|| Grub x 2|
| Whispering Root x 1|| Wanderer's Journal x 1|
in the room connecting to Ancient Basin
| King's Idol x 1|
requires defeating Dung Defender and using Desolate Dive on the floor beneath the giant valve
| Geo Deposit x 10|
| Soul Totem x 4|| Rancid Egg x 4|
Sub-area: Isma's Grove
A hidden garden accessible by using Crystal Heart to dash through a tunnel of spikes at the east end of the Waterways after defeating the Dung Defender, or through a tunnel connected to the Kingdom's Edge. The Grove houses the presumably deceased Isma, on whose corpse the Knight finds Isma's Tear, which allows the Knight to swim through acid.
Sub-area: Junk Pit
- There is an unused key in the game's files labelled "Waterways_Key" which was presumably used to open Royal Waterways instead of the currently used Simple Key.