|The following is based on Fallout New Vegas cut content and has not been confirmed by canon sources.|
The southwest sewers and its counterpart the Northwest sewers would've have been accessed from the central sewers. Large, maze-like and mostly submerged in radioactive water and the only working door being a sewer pipe to the northwest sewers.
While never actually making it in-game, the southwest sewers has several spawners for Fiends, but no actual loot or usable items are placed within the entire section.
- Random loot obtainable from Fiends
The southwest sewers were set to appear in Fallout: New Vegas but were ultimately cut.