That's why I specifically grow flood tolerant trees. I take a couple trips a year, and I just put all my dudes in basins of water, and they love it. Some just tolerate it but hell, stress free traveling. It limits the number of species you can grow but I do bonsai as a way to relax and have fun. Worrying about trees isn't fun or relaxing to me so I made the two meet in the middle. I have failed to convince anyone else here that it's a good idea haha. But if you want a list of flood tolerant trees for your zone just message me. Sorry for your loss. And I do believe all the serious nuts use timer systems when they travel. That's option 2 of course