Without knowing how the local utility company implement their Earthing system, sinking a wire into soil, concrete or plumbing fixtures may or may not achieve much,
and or score floating voltage drama.
Maybe the dude next door is playing with electricity too after watching some backyardesque Youtubes
perhaps going for it with coat hangers and leaky dumpster grade arc welder that escaped its overdue rendezvous with the metal scrap yard
AFAIK+EMMV: in a proper Earth/ground system, a UPS in battery backup mode will 'usually' supply 60 volts on both live pins to give 120 volts,
and NO EARTH/ground, unless it sources it from the UPS chassis and or output third pin out of the wall socket.
i.e. even with a UPS in backup mode via battery, you still have a non-Earth referenced floating live electrical system that can still bite you, hopefully via 'inverter to output transformer'
but not with the full force of a power station feeding a street transformer
(but chances are still good for an unplanned demise from the Earth, and consequent burial in it..)
How about a 120v isolation transformer with two 60v secondaries with a center tap between the two acting as the third pin ground-earth reference,
for a 'better than nothing, hey might even work..' portable 'ghetto Earth'?
NOTE: I will delete the above tip if it's not the 'balanced transformer' set up I was thinking of.
Otherwise, lose the shorts and flip flops,
and enter Float City with gloves, glasses, long sleeves, rubber soles
..and someone nearby with a fully charged phone