This photo shows _ inch plastic PVC pipe for drinking water. Later I was to realize that I should have bought plastic PVC pipe for non-potable water. I had some of that in my garage and compared the two. . The difference is in the pipe wall thickness. The drinking water version is twice as thick. This makes the drinking water version much stronger but less flexible. This mistake caused my initial plans to be faulty due to this lack of flexibility. The drinking water pipe costs about two dollars for a ten-foot section.