What are you going to do for water?? I had a long set that I ran 4" pvc all the way thru and just outside the first pen I rigged a float, cut a small hole in the top of the 4" pvc in every pen so the dogs could water. I used screwed ends so if I needed to wash out or something, usually kept clean chemically(bleach). It seemed like the white pvc helped keep the water a little cooler, because mine where on cement like yours I even would jam the float a little in the summer so it would run over(just slowly) keeping a little cooler water flowing in all the time. Really looking good.
I thought of something along the same lines, but the only thing that worries me about that is one dog being sick and having the same water source as the others. I know it's probably a long shot.
