Sewer

Fallout 3

 * Sewer (metro), an underground link between Pennsylvania Avenue and Seward Square.
 * Dry sewers, the basement of Our Lady of Hope Hospital with entrance from Dupont Circle.
 * Tepid Sewers, a mole rat infested raider base under ground between Georgetown and the Anchorage Memorial.
 * The County Sewer Mainline between Grayditch (Sewer Waystation) and Arlington Memorial Bridge.
 * The small radioactive sewer that is used as a super mutant base in Vernon Square.
 * A blocked sewer entrance and utility rooms, accessible via a manhole cover found in an alley in Vernon Square.
 * The sewer south of Grayditch, northeast of Red Racer Factory, with some feral ghouls.
 * A sewer south of Arlington Library containing raiders and a big stash of chems. A fairly easily missed dungeon.
 * Old Olney Sewers, a sewer system under the abandoned town of Old Olney.

There are also seven "drainage chambers" and two "sealed cisterns" for the nine Morse code "Signal" radio stations.

Fallout New Vegas
New Vegas sewers, an overview of the New Vegas sewer locations


 * Central sewers
 * East central sewers
 * North sewers
 * Sealed sewers