If you want an idea of what replacing just some of the drywall would look like and how to do it, look up "repairing flood cut drywall" on Youtube. That process is exactly what you'd need to do to remove and replace the lower section of drywall.

Well there's the other half of where you went wrong :). Please tell me you at least have a string already pulled through the pipe.

I have the same setup on my 20' wide patio but it's only a 2" pvc pipe. I made sure NOT to glue the caps on and TO have a string pre-run through to be able to pull anything if I do ever need to use it.

Good luck!

Wire seven 10' lengths of rebar together and shove it through, knocking off the cap on the other end?

How about flooding it with water to see if water comes out the other end? Or blast it with compressed air?

Haha, take that Texas. Keep voting those idiots into office that don't really give a sh!t about you. They should have learned two years ago (and so should have the voters) from the last incident.

Not a GD thing has changed since then.

Enjoy your rustic living.