The MTA has finally revealed its plans for working around the coming L Train shutdown. Beginning in April of 2019, travel between Manhattan and Brooklyn on the L will be suspended for fifteen months so much-needed repairs can be done on the Canarsie Tube, aka the tunnel between 1st Ave in Manhattan and Bedford Ave in Brooklyn, which sustained major damage during Hurricane Sandy.
The L Train won't run between 8th Ave in Manhattan and Bedford Ave during the time of the shutdown, and speculation has been rife over how the volume of riders (the MTA estimates over 400,000 people travel on the L daily) will be accommodated. The MTA's mitigation plan includes additional bus service and expanded subway service on other lines, as well as major changes to 14th St in Manhattan. You can read the full plan on the MTA's website, and it includes the following:
Increased service on the G and JMZ lines
Longer G and C trains to increase capacity (C train lengthening is also part of the broader Subway Action Plan)
Weekends and overnights, M will run to 96 St/2 Av
Free MetroCard transfers between Broadway G and Lorimer-Hewes JMZ
Free MetroCard transfers between 3 train at Junius St and L train at Livonia Av
L-Alternative buses will run over the Williamsburg Brige, where cars traffic will be restricted to vehicles with three passengers or more, taxis included. In Manhattan, 14th St from 3rd Ave to 9th Ave eastbound and 3rd Ave to 8th Ave westbound will become a "busway" without cars. In addition to the M14 Select Bus Service, three new bus routes, which you can see above, will run between Manhattan and Brooklyn: L1, between Grand St Station in Bushwick and 1st Ave/15th St in Manhattan; L2, between Grand St Station and SOHO, and L3, between Bedford Ave and SOHO.
13th St in Manhattan will get a protected two-way crosstown bike lane, and Delancey St between Allen St and the Williamsburg Bridge will get a "protected bike link." Citi Bike is also expected to expand its capacity. A new ferry route will connect North Williamsburg to Stuyvesant Cove, as well.