This is purely anecdotal, but on Saturday my wife and I dropped in to a major supermarket in a large town in the UK for some bottled water - there wasn't any.
This happens now and again, so didn't think much of it.
Today I decided to go down to a local store near where I live in the sticks - no still water in stock.
So, I decided to head down to our local supermarket that's just a couple of miles away - almost no still water to be had.
I managed to get a few bottles, but it was clear that it was going to be the last because they had filled the space that the water usually sat with boxes of fizzy drinks cans so as not to create an empty space where the water should be.
There was stacks and stacks of sparkling water however.
Like I said, totally anecdotal, but perhaps something to keep an eye out for on your travels.
I'll try and remember, no promises :P
Those bottles make it look appealing