L train to shut down for 18 months starting 2019

An East River tunnel that carries one of New York City's most crowded subway lines will be closed for a year and a half starting in January 2019.

The MTA says the tunnel needs to be closed for 18 months because of the complexity of the work that needs to be completed.  They say the recent rehabilitation of the Montague and Greenpoint tunnels were used as a guide.

While the full closure will not happen for a few years, prep work requiring night and weekend closures will begin before that.

Several alternatives are being considered for tens of thousands of L train riders between Manhattan and Brooklyn.  They include extra subway service on nearby lines, including the M, J and G lines and a new bus and ferry service. Cars also could be added to trains on the G line.

All five L train stops in Manhattan will close. L trains will continue to operate in Brooklyn between the Williamsburg and Canarsie neighborhoods.

The tunnel was badly damaged during Superstorm Sandy in 2012.  More information about the project is on the MTA website.

The Associated Press contributed to this report.