I could only conclude that my surface concrete pavers were clinging together out of habit, as they had no form of physical support.
It's a small wonder that our car hadn't fallen into something resembling an elephant trap when we arrived for the Christmas holidays.
Alarmed that the cavity might be due to some sort of geothermal activity, I called in a council engineer, who, after removing a few more pavers, disappeared underground to investigate the mystery.
What I like about engineers is they don't pussyfoot around the facts.
"You've got crook drainage. All your roof water's been spilling into this hole over the years and washed away the subsoil," he muttered, adding with a smirk: "Some cowboy didn't know what he was doing."
I didn't dare mention that I was the cowboy responsible for the work 30 years ago.
"So, what do I do to fix it?" I squeaked, wishing I was back in the effete, comfortable surroundings of Parnell - drinking latte and scoffing croissants - instead of stuck in the middle of nowhere with a serious drainage problem.
He scornfully stared back, before muttering it was easy to repair and immediately went into a long dialogue about pumice, river stones, filter cloth and sand.
Determined to undergo some sort of metamorphic process that would transform me from a wispy cartoonist into a real bloke, I retreated back to the internet to learn how to construct a drainage system.
I guess if I get it wrong this time, I won't be around in another 30 years - if my latest efforts turn into another elephant trap.