If you get the larger quart waterers there IS space for a chick to drown, even beyond a week old. I lost a 3 week old my first go around with chickens. If you don't want to put marbles in their waterer(which I understand because they can get NASTY!) I recommend purchasing a quail waterer for the first couple week. It's a very narrow base in which chicks will be unable to get stuck and/or drown.
