It seems amazing out of 60 posts that the most important part of this endeavor was only mentioned ONCE. Whether its the 'approved' sewage hose, the clear stuff, or PVC.
The SEACOCKS. I know where mine are. I make sure they are maintained. And most importantly (even at work) I have several bags of wooden plugs
) Both on a 125' 4300 HP tug, and a little 30' Ranger
. There is no issue of broken pipes (PVC or otherwise). The valves are OFF until used, shut while boat is unoccupied (Unless of course it is at work with a Duty Engineer