The New York City Department of Transportation and MTA NYC Transit have been working on plans for months.
They agree that work on the tunnel that brings the L train back and forth from Brooklyn to Manhattan will be big and an inconvenience.
On Tuesday, NYC Mayor Bill de Blasio rode an L train from Union Square to the Grand Street stop in East Williamsburg.
He asked commuters to look at alternate routes before the beginning of the work in April 2019. It is scheduled to last 15 months.
Information is available here about the NYC DOT plans for new route and enforcement of traffic rules.
The MTA is a state authority and it has control over the Canarsie Tunnel reconstruction project. There are incentives for the contractor to finish early and there are penalties if they contractor is late.
On Tuesday, MTA NYC Transit President Andy Byford held an open house in Jamaica, Queens about the subway improvement plan known as Fast Forward. That billion dollar plan will require city, state and federal support.
The City of New York partners with MTA NYC Transit to design the bus system. 80 buses will be traveling over the Williamsburg Bridge every hour.
14th Street in Manhattan will become a bus corridor during certain times.
The Mayor says the city is working to bring more bikes to Brooklyn and address NYPD enforcement of bike and bus lanes (and the high-occupancy vehicle restrictions that will be in place on the Williamsburg Bridge).
Command Centers will be set up and the city and transit agency say they will respond to needs. That includes traffic impacts on neighborhoods and on other East River Bridges.