Construction began Monday on what officials are calling a “major redesign” of 116th Street in Manhattan.

The revamp will include 2.5 miles of new bus lanes and street upgrades that the city Department of Transportation says will accelerate commutes across 10 routes for more than 65,000 daily riders.

The DOT said buses can move as slowly as a person walking — less than 4 mph — along some stretches of 116th Street.

“When your bus is moving slower than you can walk, something isn’t working,” Mayor Zohran Mamdani said in a statement. “This redesign brings together bus lanes, bike lanes, pedestrian space and proven safety improvements because our streets have to work for the millions of New Yorkers who use them every day – however they get around.”

By adding offset and curbside bus lanes, plus dedicated traffic signals that give buses a green light before other vehicles, the DOT aims to speed up M116 buses, which travel along one of Manhattan’s slowest routes.

Riders of M3, M7, M102, BxM1, BxM6, BxM7, BxM8, BxM9 and BxM11 buses will also benefit from the upgrades, the agency said.

In addition to bus upgrades, the area will see the installation of protected bike lanes on Pleasant Avenue between East 116th and East 120th streets, plus on-street bike parking.

This will create links to the existing bike lane network serving Randall’s Island and the Harlem River waterfront, the DOT said.

For pedestrians, there will be 35,000 square feet of new space and safety improvements, including three new mid-block crosswalks, median islands, new traffic signals and a speed hump.

A mural will also be added to the intersection of East 120th Street and Pleasant Avenue, according to the DOT.

Anyone driving through the area should plan around the construction, which is expected to continue through the fall.