If the owner knew a flood was coming or was negligent in flood prevention, you could probably sue. However, just because he thought that floods usually happen in the spring does not mean he was negligent or fraudulent in not warning you to get out ahead of time--by their very nature, floods are unpredictable. Given that unpredictability, it's unlikely you'd prevail on a claim--if you camp in a campground, especially one where you're told it could flood some times, you are assuming some risks, such as that of property damage from flood. That's not to say you couldn't bring a claim and win, but claims are always harder when you are engaging in an activity that has its own risks, especially if you can't show fraud or negligence on the property owner's part.Your insurance is the best place to look for compensation in a situation like this.