The added space would shorten security lines and improve customers' experiences while traveling, the authority said.
More than 23 million passengers used National last year, making it the second-busiest airport in the region, after Baltimore-Washington International Marshall Airport. Last year was its sixth straight year of record-high passenger traffic. And there is little indication it will taper off.
And that’s the problem.
But in the years since President Franklin D. Roosevelt watched the first American Airlines DC-3 aircraft touch down on the runway, the airport has grown in ways that few could have anticipated. It now serves more passengers than Dulles International — an airport 14 times its size.
The irony is that while airport officials have fought against growth at National, they have been forced to accommodate it.
They have reconfigured space, even re-purposing storage closets and conference rooms to manage the passenger boom. In 2014, they spent $37 million to remake historic Terminal A, adding security lanes and brightening the interior.
The building will replace Gate 35X — a notorious choke point where travelers, in rain, sun or snow, are required to board shuttle buses to get to their planes.
"Over the next four years, there's going to be a transformation of the passenger experience at Reagan National to decrease congestion near the gate and to improve passenger flow through the terminal," said MWAA spokesman Rob Yingling.
The authority released a video that shows security checkpoints being moved and housed under the roadway west of the airport, toward Crystal City.
Some of the checkpoints will be underground and have natural light coming in through glass ceiling panels. Terminal C, which currently houses the airport's executive offices, will be transformed to hold short-hop flights.
The authority said much of the construction will be done overnight so as not to interfere with airport traffic. The work will not begin until spring 2017 and is expected to be completed by 2021.