Did something happen to call attention to your lifestyle?
That was also my first thought. The law is very much the same here in France and I would imagine probably in the whole of Europe. Rain water for anything else than gardening and washing your car is a no-no. I don't even dare to look into the regulations for humanure. Still, many people here live under the radar, so to speak and enjoy the kind of life that you described.
I am not much good for fighting laws in Arkansas all the way from France, but I wish you good luck with your dealings with the authorities and hope that you will find help somewhere, somehow.