I don't think I've seen this question asked so I'll be that guy and ask it.

I'm sure that these starships have some sort of plumbing system in place, but how do they empty the tanks?

  • Do they do like modern day aircraft with the blue stuff which can be emptied mid flight?
  • Do they do like RVs do and stop at designated stations in space to drain the tanks?
  • Do they simply return to base and drain the tanks there?
  • Is it more like the ISS where they just shoot it out of the station?

So basically, where does the poop go?

  • 27
    In The Empire Strikes Back, we learned that Imperial Star Destroyers dump their garbage before going to lightspeed, and in the movie they dumped enough stuff that two interstellar spacecraft could be hidden in the debris. So polluting the space shipping lanes is not one of the Empire's great concerns. I don't think we needed to see coiling turds and yellow ice crystals on screen to make the obvious deductive leap.
    – Kyle Jones
    Commented Nov 20, 2014 at 22:50
  • 2
    Also, modern aircraft are not allowed to empty anything midflight. That's just television. en.wikipedia.org/wiki/Blue_ice_%28precipitation%29 Commented Nov 21, 2014 at 1:39
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    @KyleJones So that's why comets smell so bad. Commented Nov 21, 2014 at 6:17
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    @IQAndreas That's only really true if you're dumping in some arbitrary place in space but, more likely, you're going to be travelling along some specific route or parked around some specific place in some specific orbit. Social context vastly increases the risk of collision. Commented Nov 21, 2014 at 10:34
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    @KyleJones: there's nothing that make a Sith lord smile quietly to himself as much as the thought of another Sith lord's spaceship all covered in toilet waste. You can imagine the conversation at DarkSideCon - "Hey, Vader - heard you had a little accident out there! Hur-hur-hur-hur-hur!!!" And Vader thinking to himself, "Just wait 'til I get done with these Rebels - then I know of one more planet that's gonna get vaporized..!". Commented Nov 21, 2014 at 17:47

4 Answers 4


I thought the physics of the matter was the core of the question. Obviously they just leave waste in the area the ship was positioned prior to movement.

The tricky situation is the mechanics of ejecting waste. I'm going to lay a bunch of educated guesses:

Mess and Containment

I don't think that they can reliably eject raw organic waste into space. The surface tension of the water in the waste is likely to cause it to stick to the hull of the ship after 'ejection'/ This would lead to that part of the ship looking like the butt of someone who never wipes after pooping.

The trash depicted in 'episode V' is containers or compressed waste. We can suppose that organic waste could be entombed within such a container and abandoned. I don't think this is the correct line of thinking.

Sustainable Engineering

Organic waste would be immensely valuable for any space craft, isolated from an ecological environment. Systems for breakdown of organic waste and excrement are known today, and there is no reason to consider that composting would be absent, as a process – particularly when we know that it can produce energy even with the tech we have today. Much of the organic waste stream could then be tempered (see above) and used for food systems.

So I presume that any of the Star Destroyer class vessel, and above, would be sufficiently sized to make waste reclamation a worthwhile operation. In this situation, most organic waste would be reused. Anything particularly problematic to that process could be separated, dried, compressed to bricks, and ejected.


All of this presumes that the resupply periods are sufficiently long that increasing sustainability of the ship is worthwhile. This seems inevitable, but I welcome anyone deeply-read to correct me on that.

  • 5
    -1 ) this answer is pure speculation, based on real world science. This answer would be great on say Space Exploration.SE, or WorldBuilding.SE, but here the goal is to get a inuniverse canonical answer. Commented Nov 21, 2014 at 23:04
  • I'm waiting for someone to bring force with more canonical details. I agree with you in principal, but in practice the physics and systems of the Star Wars universe will be no less sophisticated. I don't see what issue you can have with that. Commented Nov 22, 2014 at 2:52
  • There's a possibility that they recycle wastes...
    – user931
    Commented Nov 22, 2014 at 7:38
  • @SachinShekhar do you know another way, in-canon, that organic waste is recycle aboard republic and/or imperial vessels of this scale, in the time period of ep.5,6,7? Commented Nov 22, 2014 at 7:55

Standard procedure for Imperial Capital Ships is to dump all trash overboard before jumping to Hyperspace, as Han Solo or Boba Fett will tell you.

HAN : Well, if they follow standard Imperial procedure, they'll dump their garbage before they go to light-speed

So at least for Imperial Star Destroyers, it seems that waste would go directly into empty space - perhaps unsanitary, but they may have a standard dumping procedure to avoid contaminating inhabited planets.

Smaller ships like the Falcon may do the same thing as needed (and for the time they spend in space in Episode V, it's almost certainly needed at some point). As for single-pilot ships like X-Wings...that is harder to explain, unless their space suits take care of that business in some manner.

And the Death Star at least had a giant trash compactor (several, in fact), so it wasn't like that waste was going to all be dumped raw and en masse.

But, at least for Capital Ships specifically, it seems they dump it straight into space as you suspected.

  • 1
    The water in the human wastes is probably recycled, leaving mostly solid matter which can be compacted before dumping.
    – Dungarth
    Commented Nov 20, 2014 at 22:19
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    I would imagine X-Wing pilots face the same issues as our modern day pilots.
    – BlueBuddy
    Commented Nov 20, 2014 at 23:42
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    It's highly likely any trash dumped near an inhabited planet would burn up on reentry.
    – Codeman
    Commented Nov 20, 2014 at 23:48
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    @Richard - but: "What an incredible smell you've discovered!" - seems unlikely to just be mechanical/inorganic junk, eh?
    – user8719
    Commented Nov 21, 2014 at 0:23
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    @Richard Inorganic waste does not "rot"; that's the organic organisms in the water that grow, spread, and cling onto the inorganic matter.
    – IQAndreas
    Commented Nov 21, 2014 at 6:07

I have to agree with Jon. A spaceship is basically a canned environment. Throwing stuff away like that is expedient, but really not practical. I guess if you have 1:1 matter-to-energy conversion capability it wouldn't make a difference, but its clear that is not the case in the SW universe. While fecal matter and urine might disgust people, its a reusable resource - with the right tech.


I doubt very much that even the Empire is stupid enough to throw away valuable organics and water on ships that house personnel long-term. So on the bigger ships, like the Imperial destroyers, it's likely to be recycled. Fighters are typically returning to their bases in short term, so probably don't have any facilities for this (probably in-suit bags for emergency use, but you don't want to use them...). It's not clear what you'd do on something like the Millenium Falcon, which doesn't seem to have a lot of onboard facilities beyond simple galley, but clearly is not a short-haul ship. Presumably, they could either dump their waste en-route (having no use for it) or perhaps they'd find a market for it (not inconceivable)

  • "Well, if they follow standard Imperial procedure, they'll dump their garbage before they go to light-speed"
    – Taemyr
    Commented Nov 21, 2014 at 13:27
  • Agreed, that's what they do, tho I regard this as an in-universe inconsistency. If you have the tech to obsolete saving organics, then you probably also have the tech to make fighting wars stupid as well. The movie needs a plot tho...
    – cod3fr3ak
    Commented Dec 29, 2014 at 3:32

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