Undercity sewers

"It can be pretty nasty down there."

- Mission Vao

The Undercity sewers referred to a sewer complex on Taris not far from the Undercity. It served as both a sewage disposal system and a hideout for various criminal elements on the planet.

Description
The sewer system consisted of several levels, connected through large metal pipes that transported sewage into large reservoirs. The complex had at least two maintenance levels, which were largely abandoned by 3,956 BBY. Several pipes were apparently missing or in gross disrepair, as raw sewage flowed directly through the maintenance levels at several points. Most of the complex was made up of what appeared to be permacrete, bolted fast with metal bolts, as well as large, rusted metal sheets, and was illuminated by several dim lamps. The system appeared to be largely automatic, and was driven by enormous, perpetually rotating gears. Maintenance and waste removal was performed by droids, although these seemed to be largely absent or malfunctioning.

Lower sewers
The maintenance level referred to as the "lower sewers" was potentially the most overrun by criminals and animals. Two ladders granted easy access to the level from the area directly surrounding the Undercity. It contained large groups of rakghouls, and served as the main base of the Gamorrean slavers. The Black Vulkars gang, fearing for their safety, set up a ray shield to keep the two factions from entering the "upper sewers" outside their base.

Upper sewers
Separated from the rest of the sewers by the aforementioned energy shield, the "upper sewers" still contained several rakghouls and slavers. The area was effectively sealed off, the only two entrances being the corridor from the lower sewers and the entrance to the Black Vulkars' base itself. The area did contain one ladder leading either out of the sewers or to a higher maintenance level, but it was blocked off.

History
The sewer system was established by Taris city some time before 3,956 BBY to manage the sewage from the the building levels above the Undercity. Over the years, maintenance of the system apparently ceased completely, leaving it rusted and malfunctioning. With the lack of upkeep, criminal elements managed to disable the manual locks of the maintenance levels of the facility, and it soon served as a hideout for Gamorrean slavers, who used the vacant complex's many small sections as holding cells for slaves. The Black Vulkars gang based in the Lower City, directly above the sewers, were forced to put up an energy shield to keep elements from the Undercity wandering through the sewers from entering their headquarters, which led to a concentration of criminal activity in the complex. At one point, a rancor managed to find its way into one of the maintenance levels of the sewers, settling in the north-east and surviving by eating passers-by.

When the amnesiac former Dark Lord of the Sith Revan entered the Undercity in order to rescue the Jedi Bastila Shan from the Black Vulkars, he encountered Mission Vao, who offered to help him enter the Black Vulkars' headquarters in exchange for helping her save Zaalbar, her Wookiee companion, from the Gamorrean slavers in the sewers. Revan agreed and entered the complex, killing several rakghouls and Gamorreans, eventually rescuing the Wookiee, who swore a life-debt to him. In return for freeing Zaalbar, Mission deactivated the shield hindering access to the Black Vulkars' lair from the sewers. Revan then encountered the rancor in the north-east of the complex, but was able to trick it and enter the Black Vulkars' base.

Rakghouls
The rakghoul disease was a deadly malady that turned its victims into savage rakghouls. The beasts, shut out from the Undercity by a large metal wall, were forced to look for food, and possibly shelter in the sewer complex near the village. They soon infested large parts of the sewers, becoming a large threat to the Gamorreans, who attempted to kill them off by sealing them inside small rooms and starving them to death.

Rancors
A large rancor somehow managed to find its way into the sewers around 3,956 BBY, likely looking to feed off the large amount of Gamorreans, rakghouls and Sith patrols in the area. It operated out of a large hall just outside sewer entrance to the Black Vulkars gang's base, severely restricting access both to and fro.

Inhabitants
"Those Gamorreans like to hang out in the sewers. The stink reminds them of home, I guess."

- Mission Vao

Black Vulkars
The Black Vulkars gang, led by Brejik, controlled both entrances to the upper sewers, which may have contributed to the lack of maintenance in the area. Their base may have once been a part of the sewer complex; pipes from the sewers adorned the walls in several places, and the doors carried the symbol of Taris city.

Gamorreans
A group of Gamorrean slavers operated out of the lower sewers, capturing passers-by and likely selling them to other criminal groups on the planet. People wandering the lower levels of Taris were unlikely to be missed, which substantially lowered the risk of being discovered by Tarisian security forces. The Gamorreans were possibly affiliated with Davik Kang, the leader of the Exchange on the planet, who was said to have a hand in everything on the lower levels, even slavery. The Gamorreans probably suffered large losses in 3,956 BBY, both when Revan cut his way through the sewers, and when Darth Malak's Sith forces bombarded the planet.

Hidden Beks
At least one associate of the Hidden Beks gang visited the sewers looking for a way to enter the Black Vulkars' base. He carried vials of synthesized odor with which he hoped to lure the rancor outside their base into eating something that would cause it internal injury. However, the Hidden Bek was killed by the rancor before being able to carry out his plan.

"Promised Land" believers
At least three villagers from the Undercity traveled into the sewers to find the "Promised Land," a mythical location on Taris said to be completely self-sufficient. All three perished in the complex.

Sith
The Sith Empire, looking for escaped Republic soldiers whose escape pods had crash landed near the Undercity, sent several patrols into the sewers, but at least a few participating soldiers were killed, probably by either rakghouls or the rancor.

Appearances

 * Star Wars: Knights of the Old Republic