LaGuardia Airport is bracing for another bout of congestion as travelers take to the air for spring break while the airport continues its massive reconstruction project.

More than 800,000 travelers are expected to pass through LaGuardia between Wednesday and April 17, according to the Port Authority, which operates the airport.

Travelers should give themselves plenty of time to reach the airport and board their flights, the agency said.

People should use mass transit if they can, and they can ride for free between Wednesday and April 17 on the Q70 Select Bus Service linking the airport with Long Island Rail Road and subway stations in Queens, the Port Authority said.

The first phase of the airport’s reconstruction began in June as a private developer began building a new parking garage and a new main terminal, also known as Terminal B.

A second phase involving a new terminal for Delta Air Lines has not begun.