A partial Blue Line shutdown and major delays on two other Metro lines began Saturday, prompting WMATA officials to warn riders "to only use Metrorail if you have no other option."

Through Aug. 26, Blue Line trains are running only between Franconia-Springfield and Arlington Cemetery, with no Blue Line service in the District or Maryland.

In addition, Orange and Silver line trains are operating only every 20 minutes, which could lead to extensive delays and crowding, Metro said.

"All Orange, Blue and Silver line customers are encouraged to use alternate transportation and to only use Metro if you have no other option," Metro said in a service advisory on its website.

Would-be Blue Line riders who need to travel between Virginia and downtown D.C. should use the Yellow Line instead, Metro said. Extra Yellow Line trains will run during rush hour between Franconia-Springfield and Greenbelt.

Between Franconia-Springfield and Arlington Cemetery, Blue Line trains will run every 16 minutes during rush hour, every 12 minutes after noon and every 20 minutes after 10 p.m.

Travel alternatives include:

Other Metrorail lines and stations

Metrobus

DC Circulator (which includes a stop in Rosslyn)

ART buses

Fairfax Connector buses

VRE and MARC trains

OmniRide (to and from Prince William County and Manassas)

Metro has posted travel options and a map of what the system will look like during the shutdown on its website.

On the weekends of Aug. 11-12 and Aug. 25-26, free shuttles will replace train service between Foggy Bottom and Federal Triangle. Metro Center will only serve Red Line trains while the Farragut West and McPherson Square stations will be closed.

During the weekend of Aug. 18-19, Orange and Silver line trains will single-track between the McPherson Square and Smithsonian stations at all times.

WMATA is also in the midst of a shutdown of the Red Line between Fort Totten and NoMa-Gallaudet, which started in July and is expected to end on Sept. 3, Labor Day.