MANHATTAN — Part of a major east-west corridor in northern Manhattan — 181st Street — will get a dedicated busway starting April 26, Mayor Bill de Blasio announced Friday. 

The long-awaited busway, which was expected in 2020 and then delayed, will help speed bus transit across a half-mile section of the road, which divides Washington Heights from Fort George, for the route’s approximately 60,000 daily riders.

Currently buses from both Manhattan and the Bronx journeying along 181st Street travel at 4 mph on average, according to the city. The slow speeds disrupt commutes for passengers transferring to the A and 1 subway lines, and to the George Washington Bus Terminal, a major destination for people commuting from New Jersey and between Manhattan and the Bronx. 

“Washington Heights deserves faster, safer, more reliable bus transit. The 181st Street busway will help this iconic neighborhood come back stronger than ever,” de Blasio said in a press release.

The busway will follow a traffic model already in use on 14th Street in Manhattan, Jay Street in Brooklyn and Flushing-Main Street in Queens. 

Only buses, trucks and emergency vehicles will be able to drive the length of the road, while cars and other vehicles will have to exit the road to the right after one block. 

The priority lane in the eastbound direction will stretch from Broadway to Amsterdam Avenue -- about four blocks -- and Amsterdam Avenue to Wadsworth Avenue in the westbound direction, about three blocks.

There will be no busway east of Broadway on 181st Street. 

Local parking will be allowed, and new cameras along the bus route will send tickets to violators of the bus lane for its first 60 days.