I understand the problem, and there is no easy solution. I don't believe that the government should be able to tell someone that they cannot build (or move their home) on their property. If they do prohibit it, I think there would be a Fifth Amendment taking and the government would have to pay just compensation.

However, perhaps we are getting to the point where we need to modify the federal flood insurance program. Maybe there should be some locations that are just uninsurable? Where people could build at their own risk? Like I said, no easy solution.