Travelers heading to or from Reagan National Airport should get ready for traffic impacts from construction starting next week.

Work will begin overnight from Monday, February 19 into Tuesday to prepare the building foundation for the new security checkpoints.

Roadway disruptions will initially be confined to overnight lane closures near terminal B/C, but will extend into the afternoon and evening hours later in the spring.

A project press release adds that “some temporary changes are coming inside the terminal that will affect the airline check-in process for some passengers.”

Nicknamed “Project Journey,” the one billion dollar infrastructure enhancement is scheduled to run through 2021. The finished project will bring two 50,000-square-foot buildings with security checkpoints, replacing three smaller checkpoints at terminal B/C. A new 14-gate concourse is in the works, which will include an American Airlines members lounge, replacing the notoriously difficult to access Gate 35X.

The airport has vastly outgrown its original passenger projections. It now serves about 24 million travelers a year, as opposed to the 14 million it was built to accommodate.