I have crawdads in my yard too. I bet at least 50 holes. I know it is crawdads because i have seen them and there holes are at least 800 feet from the nearby stream. My yard is level and doesn't hold water but the soil is soft. Actually, my yard use to be a garden years ago. I don't know if this is legal or not but I have recently been told to put one piece of carbide down each hole to get rid of them. I will try it this spring.