The incident happened at around 10.30 pm last night when the pillar was found leaning on the on the Diamond Harbour Road at Behala tram depot crossing, a police officer said.
Nobody was injured in the incident as alert metro workers removed the iron pillar, a senior Metro official said.
Traffic was partially stopped on the road as senior officials of Metro Railways besides a team from the Behala police station rushed to the spot.
Traffic resumed at that stretch within hours, a traffic official said.