Resisting Back Passage Double Entendres

The saga of the mouldering wall continues. We're pretty sure it's due to a leaky pipe which carries rain water from our back garden into the street out front and runs the whole length of our living-dining-room wall. The wall is stone and porous; the pipe is probably ancient.
Our insurance man came and had a look and then our next-door neighbour's insurance man came and had a look. They took the standard couple of months to think about it and then they sent a man with a camera to do a videoscopy.
He trailed all of his equipment through the house into the back garden. He inserted a long tube with a mini camera on the end into the pipe and recorded the pictures it sent back on his laptop. Afterwards, in an experience which is as close as I hope ever to come to seeing the insides of my own bowels on a monitor, I got to watch the video footage of the crumbling pipe that lies under the house and the dead leaves and débris that litter the bottom. And just like a doctor, the man announced after the procedure that he had good news and bad news: the good news being that he had diagnosed the source of our affliction, the bad news that the treatment was going to cause major financial haemorrhage.