Had to dig up a city water line that couldn’t be shut off due to a failed valve. Was particularly aggravating to incur the effort and expense to deal with failed city infrastructure. Despite that it was an interesting adventure and one I knew that eventually I’d have to face. You can only buy so many hideous old shacks before you unearth a gremlin. Luck was on our side with a trench filled 9 ft down with pea gravel and soil conditions resistant to caving in. We were also blessed with the best equipment and operator to do the job. Another lesson in network equaling net worth, for me it is more network = get it done easy and quick.
Trade secrets involved in shutting off the pressurized water line with no means of shutoff upstream.