Is there a laundry service aboard? Do they save up dirty uniforms until meeting up with a sub tender? Really curious about that. Seems like the water needed would make it a logistical PITA.
There are washing machines and dryers on American subs. I imagine all modern nuclear boats have them, and probably even most modern diesel-electric subs.
A side note, these are pretty specialized affairs on the American subs, being made to certain noise and efficiency standards, not to mention being able to withstand odd angles and whatnot, and are purchased in fairly small quantities. So they are pretty expensive (economy of scale and all). So the next time you hear about the military overpaying for Common Household Item X, withhold judgement until you know if it really is a common household item, or if it was specially designed and built for specialized use. 
Keep in mind that modern submarines have the luxury of a nuclear power plant, with full steam plant. Hence, they can run their distillers 24/7. I did not serve on a submarine, so I cannot speak to specifics, but they surely produce as much water as they please.
It appears that even in WWII, they had distillers with 1000-2000gal/day capacity onboard: a very dull looking Naval manual on WWII-era submarine distillers
Having had the honour to have been given a guided tour of a Los Angeles class SSN back in 1989 (the “Helena”), I can confirm as an eyewitness that there is (or certainly was then) a washer & dryer on board. IIFC, it was not much bigger than your average domestic unit, and I recall it just kind of seemed plunked down (or maybe “squeezed in” is a better phrase) alongside one of the messes (the men’s, I think).
The only reason I took note was that it just underlined how even in such a modern sub (the Helena was pretty much brand-new), every square inch of space counted, and had to be used to its utmost.
While I never asked, I would bet money that access was organized by watch; and further that you did your own laundry (or worked out a deal with a buddy to cover off); I doubt very much if a sub carries superfluous personnel just for laundry–I think there are several ex-USN “bubbleheads” on the board who can give us the real SD on this, however…
I remember going past the comms room (or whatever it was properly called), and seeing a poster of a (then) Soviet Typhoon class sub with a caption saying “Kill the Bastards!” The officer taking my friend and I around pulled the door closed and said “Oops–you weren’t supposed to see that!” (The comms room, I assume, not the poster.) After all, we were civilians (and furriners, at that).
Former bubblehead here…
688 Fast attacks have one washer and one dryer located outside the auxillary machinery space on the lower level. The washer is an upright frontloader and uses a minimum amount of water. However, if there was a problem with the main distiller, the washing machine was the first to be secured from use.
Wash days were by departments, for instance, Combat Systems on Tuesdays, Navigation on Wednesday, officers on Sunday. Everyone does their own laundry, except for the officers, whose laundry was done by a mess specialist.
I served as an officer aboard a Los Angeles-class attack submarine.
There is only one washer and dryer for the 130+ men aboard the sub. Both are rather small industrial-type front-loaders, stacked on top of each other. Each sailor does their own laundry, except for the officers. The wardroom actually had a sailor assigned to serve meals and do our laundry. Rank hath its privileges and all… (Actually, I don’t recall refusing laundry service to be an option.)
I’m pretty sure most of the Chief Petty Officers had junior sailors to do their laundry as well, though on a more informal basis.
Water was not an issue, so long as the main evaporator was up. If the evaporator went down, laundry and showers were secured for all personnel except for the mess cooks/food handlers. (Note that there was also a back-up distilling unit to ensure a supply of make-up water for the steam plant.)
Oh, and the Radio Room is probably the most restricted area of the boat because of the crypto issues. Nobody was allowed access without a TS clearance and demonstrated need. It is (or should be) locked at all times.