This sort of incident (which occur for a variety of reasons but usually related to lack of investment and maintenance) is narrowly avoided a lot more often than you might imagine. Because it’s avoided by desperate last minute scrambling you just don’t get to hear about it.
That’s not fair. NI Water have had to deal a terribly under-invested infrastructure compared to the rest of the UK and that was a result of pipe bursts. Nothing to do with availability of drinking water.
You want they should send two pipes to your house?
Anyone who doesn’t like using drinking water to flush the bog should capture their own grey water and send it to the toilet. It’s not the water companies fault, it’s yours.