Due to capital improvements scheduled to begin this year, Metro announced on Tuesday that service on the Yellow Line over the Potomac River will temporarily close beginning in September. The transit agency has several large-scale construction projects underway, from opening a new Potomac Yard Station and Silver Line extension to rehabilitating Yellow Line’s Potomac River tunnel and bridge.

Service on the Yellow line between Pentagon and L’Enfant Plaza will close for eight months beginning Sept. 10. During this time, crews will perform safety repairs, like rehabilitating the steel-lined tunnel near L’Enfant Plaza, which Metro’s chief engineer says is a top priority because of water intrusion. The steel-lined tunnels between Pentagon and L’Enfant Plaza stations were originally constructed more than 40 years ago, according to Metro. The agency says information about alternative travel options will be made available three months before the closure goes into effect.

“While service outages can be disruptive, we know they are foundational for maintaining safe and reliable service,” Metro General Manager Paul J. Wiedefeld said in a statement. “We have a lot of work to do this year and we will tackle major state of good repair projects while also introducing new service. We are committed to providing our customers with reliable alternatives and frequent updates on the work as it is conducted.”

Construction at Potomac Yard Station will also require a six-week closure south of Washington National Airport station. The shutdown of rail service is expected to last between Sept. 10 to Oct. 22. That’s on top of a previously announced summer closure of five Orange Line stations.

The multi-year, multi-billion-dollar capital investment in 2022 will produce much-needed repairs, along with new service — but also adds delays during an already disruptive year. Riders saw major disruptions after Metro pulled 7000-series trains due to safety concerns — and those trains, which amount to two-thirds of its fleet, won’t return to service until April, the earliest.

The Yellow Line closures impacts service to Reagan National Airport and occurs during an especially busy travel season. In November and December of 2019, an average of 5,300 people tapped their SmarTrip cards at Reagan National Airport. Alternatively, riders could take the Blue Line to the airport, but trips are likely to be longer and more crowded.

Wiedefeld, who announced he’s retiring soon, recently defended Metro as providing “very good service” in a recent Council oversight hearing. Many riders strongly disagreed. “As someone who had to wait 20 mins for an Orange Line train because I missed it by two minutes, I don’t think that it’s a good service,” one user tweeted in response.

Jordan Pascale contributed reporting.