I also dont recall drinking fountains in Phnom Penh or Saigon's airports.
So I'm not sure what you are talking about. Maybe some of the smaller regional ones?
I didn't say that there wasn't one (now or then), only that I couldn't find one, and that an employee told me there wasn't one—and both those facts are true.
Also... "Responding to Prof Colbourne's comments, a spokesman for airport operator BAA said drinking fountains offering free water were already installed at Heathrow, Gatwick, Stansted and Southampton airports."
This is from 2002... http://www.dailymail.co.uk/health/article-355500/Free-water-...
http://www.heathrowairport.com/static/Heathrow/Downloads/PDF...
Gatwick: "once you're through security, you can use our water fountains or any of our food outlets will be happy to provide you with a glass of tap water."
http://www.gatwickairport.com/at-the-airport/flying-out/secu...
One potential hack around this is to find the disabled bathroom, which usually has taps with adjustable water temperature,
Ireland is not in the Schengen area