Recently (like two weeks ago) we had tap water with our meals at the following restaurants in addition to our drinks, etc.: Ocean Lounge, Chesterfield's, The Green House, Mark's Place, Sunset Beach Bar & Restaurant ... all on the Dutch side and 1). all these places were happy to provide it, and 2). it tasted great. There were zero ill affects. Absolutely no issues at all on the Dutch side. However, on the French side we only had drinks, beer or soda at Yellow Submarine, Perch Bar & Grill, and at Friar's Bay. So, I would suggest following the advice of the above posts and go with bottled water on the French side, but no worries on the southern side of the island!