Metro plans to take advantage of the lower ridership brought on by the coronavirus pandemic to accelerate its platform rebuilding project, extending this summer’s planned shutdown to nine stations, including everything west of Ballston.

The change to the shutdown schedule, which begins Memorial Day and lasts through Labor Day, means there will be no Silver Line service.

“Closing the stations to get the work done while ridership is historically low allows us to limit the exposure of our front-line staff and contractors, move aggressively on our capital program, and minimize inconvenience to the public,” Metro General Manager Paul J. Wiedefeld said Wednesday.

Metro had originally planned to close three Orange Line stations to rebuild deteriorating platforms at Vienna, Dunn Loring and East Falls Church. Platforms at West Falls Church were also scheduled to be rebuilt.

But with the District, Maryland and Virginia under stay-at-home orders to help stop the spread of the virus and all but essential businesses shut down, the transit agency decided to take advantage of the time to get more work done. Adding the Silver Line stations will allow the agency to do advance work in preparing for the opening of Phase 2 of the line extension, the agency said.

Metro has been actively discouraging riders from using transit since mid-March, when the virus began to threaten the region, to prevent its spread. It has cut back both bus and rail service hours and closed 19 rail stations and entrances at nine stations. The result: As of Tuesday, rail ridership was down 95 percent compared with a similar day pre-pandemic.

The summer project is part of a three-year plan to rebuild platforms at 20 of Metro’s 45 outdoor stations to fix years of wear and structural deficiencies. The capital project, expected to cost $300 million to $400 million, was the first major undertaking by the agency after securing $500 million a year in dedicated funding.

The first phase, completed last summer, was a 107-day shutdown of six Blue and Yellow Line stations south of Reagan National Airport.

Staging for this summer’s project began last month with the closing of surface parking lots or spaces at East Falls Church, West Falls Church and Vienna stations. They will remain unavailable for seven to nine months.

The revised plan also expands the work area to give construction workers more space to spread out and move about to help reduce their risk of contracting or spreading the novel coronavirus, Wiedefeld said.

Wiedefeld described the cumbersome process of replacing the heavy concrete platforms as requiring construction crews to work like “ants” on top of one another, with workers working in concert from the track up to the platform canopies.

“That just doesn’t work in this environment, so the more room we give them, the more flexibility they have,” he said. “As you can imagine, we’re balancing a lot of things, but first and foremost is the safety of our people and our contractors.”

The Metro board will review the expanded plan at its regular meeting Thursday.

Stations that will close for the four-month project beginning May 23 are East Falls Church, West Falls Church, Dunn Loring and Vienna on the Orange Line and McLean, Tysons Corner, Greensboro, Spring Hill and Wiehle-Reston East on the Silver Line.

Phase 1 of the Silver Line extension opened in July 2014, with five stations — four in Tysons and one in Reston. Phase 2, under construction, has six stations, including one at Dulles International Airport, and will extend Metro into Loudoun County. The project, being built by the Metropolitan Washington Airports Authority, has been plagued by delays and construction flaws and is nearly two years behind schedule. Wiedefeld has said passenger service, originally slated to start this year, is unlikely to begin until 2021.

The agency will use this summer’s shutdown to do required testing needed to connect the two segments. Metro had said last year that it would need to close Wiehle-Reston East station and possibly other tracks or stations for 13 weekends of tests before the second phase could open. By shutting down the entire segment for the summer, “we have the opportunity to get it out [of the way] in one shot,” Metro spokesman Dan Stessel said.

The transit agency said about 1,200 customers use stations west of Ballston on a typical weekday, or 5 percent of the ridership that would normally ride Metro before the pandemic.

Three of the stations targeted for the project — Greensboro, McLean and East Falls Church — are already closed indefinitely as part of Metro’s coronavirus response plan to decrease the number of employees exposed to the general public while also limiting the amount of deep cleaning required in the system to save on dwindling disinfectant supplies.

The agency continues to encourage the public to use the system for essential trips only.

For riders, including essential front-line workers, the transit agency said it will provide free shuttle buses outside the closed stations to ferry people between stations. Metro is counting on the decrease in road traffic from closed-down businesses, shelter-in-place recommendations and telecommuting to limit inconveniences and delays for riders who use the shuttles.

“From a passenger impact, it would be relatively minor,” Wiedefeld said.

It’s unclear what the impact might be should the Washington region reopen in May or June. Several states plan to begin lifting restrictions on businesses as early as this week. Washington-area leaders have given no indication that they are close to lifting restrictions that limit public gatherings and nonessential travel.

D.C. Mayor Muriel E. Bowser (D) has extended a stay-at-home order and the closure of most businesses until May 15. Maryland’s similar order is indefinite, while Virginia has a stay-at-home order imposed until at least June 10.

If Maryland, Virginia and the District lift restrictions between now and September, Metro will not be able to reopen the stations if they’re undergoing heavy construction. Wiedefeld said Metro is planning for that scenario, proposing to increase buses to serve as bridges to rail lines.

“We hope that’s a problem we have to deal with,” he said. “I wish I knew what the future holds. If ridership comes back, we do have a backup plan on the bus shuttle operation to provide more buses.”

As things stand now, shuttle service will be provided between Vienna, Dunn Loring, West Falls Church and Ballston; express service with no intermediate stops will be available between Vienna and Ballston; and a third route will run between Wiehle-Reston East, Spring Hill, Tysons and Ballston.

Shuttles will run about every 10 minutes between 5 a.m. and 9 p.m. on weekdays and every 15 minutes between 8 a.m. and 9 p.m. on weekends.

Metro began its platform replacement project last year. Of its 91 stations, 45 outdoor stations have concrete platforms built more than four decades ago, nearly half of which are crumbling because of age, wear and years of de-icing, Metro said.

The new platforms include slip-resistant tiles, LED lighting and illuminated handrails. Map displays and signs are digital, while platform shelters include charging ports.

Metro had initially planned to take four Green and Yellow Line stations offline this summer for the next phase but changed course in December, postponing that work so it could better coordinate with a signal improvement project needed for tracks on those lines. The agency instead moved up work on the Orange Line before announcing the much more ambitious summer plans.

Remaining stations scheduled for platform reconstruction include Addison Road, Arlington Cemetery, Cheverly, College Park-University of Maryland, Greenbelt, Landover, New Carrollton, Prince George’s Plaza, National Airport and West Hyattsville.

Metro said that by shutting down stations to replace platforms rather than scheduling work during off-hours or weekends, it can shave years off the project.

“This is about two things: working smarter and working safer,” Wiedefeld said.