Originally Posted by
Often1
This was likely a system failure. The potable tanks and the chemical fluid for the loos are not the same and operate on totally different systems (for fairly obvious reasons). Thus, unlikely the aircraft ran out in the sense that the supply was used up.
To clarify, it was stated by the CSD that the problem “affected use of the toilets” so having not checked directly myself, it may have been the case that they still flushed but there was no water from the taps. I made an assumption based on the way it was phrased in the announcement