20 Things to Find in a Sewer

Adventurers always seem to be venturing into noisome sewers in search of wererats, skulking thieves and other, more sinister, threats.

By Bradley K. McDevitt

By Bradley K. McDevitt


Use the table below to generate the details of minor discoveries the party may make while adventuring in a sewer. Such discoveries could be nothing more than a point of interest or could spawn an entire encounter.

  1. A mouldering, slime-covered rat corpse lies on a ledge. It’s eyes are missing and its tail has been partially chewed off.
  2. A slimy pile of excrement and mud partially fills the sewer channel.
  3. Bricks have come loose from the ceiling and water dribbles through the gap.
  4. A pocket of noxious gas fills this part of the sewer. Characters breathing in the gas must make a DC 12 Fortitude check or become sickened for 1d6 minutes.
  5. Slime and ooze covers the walkway, making it very slippery (+5 to the DC of Acrobatics checks).
  6. Bats nest on the ceiling. Bright lights disturb them and they flap about until the intruders leave.
  7. Bricks have come loose from the wall, and water oozes from the gaps. This make the wall slick (+5 to the DC of Climb checks) and the floor similarly slippery.
  8. The air in this section of the sewers is fetid. The stench is overpowering and negates any scent ability the party may possess.
  9. A thick miasma hangs in the air. Tendrils of a fog-like vapour rise from the fetid waters and provide concealment (20% miss chance) to anything more than 20 ft. away.
  10. If the party possesses any naked flames, they suddenly turn blue as they encounter strange gases in the air.
  11. The loud sounds of dripping comes from up ahead. Shortly thereafter, the party discover the roof has partially caved in over the sewer. Water drips down from above, and the rubble from the collapse has created a dam of sorts.
  12. A great mass of rubbish and detritus has formed a veritable island that almost completely blocks the flow of water through the sewer. Tracks of small creatures—probably rats—are easily visible in the island’s “mud”.
  13. A mouldering red cloaks floats in the water.
  14. An extinguished lantern stands on a walkway. Of the owner, there is no sign.
  15. Faded and smeared chalk sigils once decorated this wall, but they are now illegible.
  16. A glimmer of light comes from up ahead. When the party reaches the light, they discover a narrow hole in the ceiling enables a thin beam of sunlight to reach into the sewers. The air here is a little clearer.
  17. An iron-bound door pierces one wall of the sewer. It is old and swollen and hard to open. It is also barred from the inside—clearly someone values their privacy.
  18. This sewer passageway is old and decayed. Part of one wall has fallen away creating a rubble field to scramble over. Characters exploring the collapsed wall discover a small, dry natural space beyond. The foundations of a large building intersect the area.
  19. The water in the sewer flows rapidly in this narrow section of the sewers.
  20. At this point, several sewer passageways come together in a rough cross. The flow of so much heavy, turgid water has eroded the bottom of the intersection, and now a lazy but powerful whirlpool draws the waters into yet deeper caverns.

GM’s Miscellany: Urban Dressing

If you enjoy the table above and like dungeon dressing, Raging Swan Press has got some books for you! Check out Alternate Dungeons: Infested Sewers, GM’s Miscellany: Dungeon Dressing and GM’s Miscellany: Urban Dressing; all are crammed with information and charts designed to bring your campaign alive!


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