You don't say if the animal was trying to access the water reservoir or somehow attracted to it. If it wasn't interested in that, then it means that a self-watering planter is not important here. It is the animal.

If you know what the animal is that was doing that, you can try to discourage it somehow. And in case it was attracted to the chamomile, then if you don't have it this year, you may also be OK.