Our sewer line argues for dry toilets.

Like a lot of people living in older houses with clay-pipe sewer line, we've occasionally had to call the plumber over the years (ours is good, if you need a recommendation) in order to ream the roots out of the age-weakened, perforated pipe sections. Since we've been dry-toileting, I've been worrying about this a lot less, which turns out to have been a mistake. Against the advice of our plumber, we've shied away from dumping the acid foam products down the flush toilet in order to periodically eat away at the ever-clogging root balls. And until the moment in the future when we can afford to completely grey-water our old plumbing, the shower and sink (and yeah, sometimes the flusher, under certain circumstances) all use the sewer line still. Until now, the root problems have been minor. But now, apparently, we've got some major excavations to attempt, through concrete things. The worst.