I will check with a couple LEOs, but I think if you were to bury something like a pipe or bucket anywhere in a city:
1. Local druggies or homeless would dig it up and make off with it in a heartbeat.
2. LEO or union workers would stop you unless you did a stealth, dead-of-night job.
3, Digging any such thing up would subject you to the attention of the above groups.
There are eyes everywhere and the first thought about any out-of-the-ordinary activity: terrorist.