Fixing all the damage inflicted on the South Street subway station by Superstorm Sandy may take up to three years.

Last month, the MTA said the repairs would take at least a year.

But on Thursday, the agency said it estimates that fully restoring the station would take much longer and cost $600 million.

That includes $350 million for physical repairs; $200 million for signal replacement; $30 million for third-rail equipment and $20 million for line equipment.

The South Ferry subway station, at Manhattan’s southern tip, was inundated with water up to its ceiling during the storm.

The No. 1 train station underwent a $545 million renovation and expansion in 2009.

The station is a major conduit to the Staten Island and Liberty Island ferries.