Where does the water in real Irish Guinness come from?

I'll take a cold one!

Touring the mammoth Guinness brewery, we saw what it takes to produce three million pints (a quarter-million gallons) of beer every day. The city of Dublin used to complain that the factory took too much water from the river Liffey that flows through town. Guinness insists that it uses no river water, only pure spring water from the nearby Wicklow mountains. Given that the Liffey originates in the Wicklow mountains, that gives Guinness lots of flexibility to describe their water source. In any case, there is certainly no water shortage in Ireland. Up in the mountains every scratch in the dirt becomes a little stream.

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