WASHINGTON (CBSDC) - Metro will be conducting weekend track work causing nagging delays for passengers.on the Red, Orange, Green and Yellow lines.

Metro says free shuttle buses will take to place of trains on the Green line between Archives and Waterfront starting Friday evening and lasting through Sunday.

Passengers taking the shuttle bus should tack on an additional 20 minutes to their estimated travel time.

There will be no service on the Yellow line between Fort Totten and Pentagon, causing expected delays of 15 to 20 minutes for passengers forced to use other lines to reach their destinations.

Trains will also be single-tracking on segments of the Red and Orange lines throughout the weekend, causing 20 minute delays.