Good points. The airline is PVC from my house down to the backside of the dam and then I switch to the weighted hose from there to down into the pond. This section is ~8" buried the whole way so I can mow over it. I've never seen voles or moles or gophers or anything like that. Obviously, we have rats and mice, and the highest density critter is actually crawdads. I'm just surprised that it's happening at this depth, if it was laying on the surface, I'd understand. Here's a picture of it, sorry I started to repair it with the white rtv, but you can see on the right hand side the pits and divots taken out of it.
