I've been on a number of flights without water in the airplane's internal system over the years . . . .

Sometimes, in the winter, the lines freeze. Once, a drain heater didn't work. I've seen the tiny sanitizing wipes in the lav on RJs MANY times. There should at the very least be bottled water on board, I think, but they can't use that for coffee, I don't think, since the water to the coffee makers is from internal lines from a tank - LORD only knows where!!!

Once, not a water issue, but, on a CR7, I think, the GA announced that the one and only lav was out of order for a CVG/PIT flight - - it's only 40 minutes, she said. Pushed back - delayed. Almost 2 hours from gate to gate! Ugggh!