You will get a wide variety of answers on question #1. Duck meat is highly variable depending on the breed and how it was prepared. There can be big differences between the domestic Mallard-derived breeds (all domestic ducks basically minus Muscovy), Muscovy, and Muscovy-hybrids.
Domestic duck meat other than Muscovy meat can be rather oily and gamey in taste. If you cook it in the rendered fat (one of the more common ways to cook duck), it can taste almost like dark turkey meat (like braised turkey leg) to me personally. If you prepare it in the traditional method for crispy duck where you separate the skin with air, it can taste almost like chicken. That is my personal favorite way to eat duck. The difference with Muscovy meat is that it is leaner. I have heard some people that love Muscovy meat describe it as similar to a nice, lean steak. So, it all just depends.
As far as raising ducks, no- they don't need swimming or bathing water. Of course, they love it, but they will do fine with or without it. They do need a water receptacle deep enough to submerge their head in if at all possible though.