Although it's been mentioned before, I'll say it again, I think water is extremely unlikely.
1. Water is hard to build, yes, water is hard to build.
. At regionals, if you're looking at a robot playing field with the 2-D layout of this year, and then you think about going about roughly 6 feet high. That' is a LARGE field. Also a lot of water. FIRST makes challenges, but I don't think they are cruel.
2. About Dave's fish, I have hypothesis about that. it could be that he's just trying to get the hype up about the feared water game or that the field this year will be "bumpy". The fish has scales and is generally bumpy. Expect terrain this year.
With the FTC game having some soft of terrain this year, I wouldn't be surprised to see the FRC game have some sort of terrain as well.