While drilling a hole to hang a towel rod in a first floor bathroom, I drilled into the PVC waste line that comes from the upstairs bathrooms. I cut away a section of the drywall and can see I hit almost dead center into a 2 or 3 inch PVC waste line. The hole is approx. 1/2" in diameter. Is there an easy way to fill the hole or will I need to get that section of pipe replaced?

You will most likely be advised by other experts to replace the bad section of pipe but I like a simple repair best. Get a piece of PVC in the correct pipe size and cut a one or two inch patch out of it. Now dry off the pipe and prime both the patch and the pipe. Slaver on PVC cement and hold the patch over the hole until it sets up. Don't use for a hour or so. Ordinarily I wouldn't recommend this if this were a pipe under pressure but drainage hasn't any pressure behind it and the patch should last the lifetime of the pipe. If that don't grab you you can purchase a saddle clamp,(see image) and patch it that way good luck, Tom

Thanks for your quick response, I will give that a try.