In 2005, during the reconstruction of Route 9A, the roof of the Battery Park Underpass was extended to the north by about 80 feet to provide a U-turn lane and amenities for pedestrians and bicyclists.
During Superstorm Sandy, the tunnel filled completely with seawater and required major repairs.
There have been three proposals to extend the tunnel north on the FDR Drive side.
In 1971, it was suggested that the South Street Viaduct be turned into a tunnel, essentially extending the underpass north to the Brooklyn Bridge
In 2002, the Downtown Alliance, the local Business improvement district, called for a 350-foot (105 m) extension to the underpass to create a plaza in front of the Battery Maritime Building. The estimated cost was $70 million.
In 2005, Mayor Michael Bloomberg also called for an extension of the underpass near the Battery Maritime Building as part of a plan to rehabilitate the South Street Viaduct.