06/17/2012 11:53 pm ET Updated Jun 18, 2012

Metro Rush-Plus Service Goes Into Effect For D.C. Rail System

WASHINGTON -- After months of planning, Metro's new Rush-Plus rail service pattern is going live on Monday, impacting thousands of commuters, especially those in Virginia.

While there are no new stretches of track going into service, the destinations of many trains will change in an effort to reduce a rail bottleneck at the Rosslyn station, where Orange and Blue line trains merge going into the tunnel under the Potomac River.

Some rush hour Blue Line trains originating from the Franconia-Springfield terminal will be rebranded as Yellow Line trains and diverted to the District of Columbia via the rail bridge over the Potomac River between the Pentagon and L'Enfant Plaza stations and continue on to the Green Line's Greenbelt terminal.

While that will boost the number of Yellow Line trains heading to the eastern end of downtown D.C. and Maryland from places like Alexandria and Crystal City, it will mean there will be fewer Blue Line trains during rush hour heading through Rosslyn. But that will allow more rush hour Orange Line trains and fewer delays at the track junction at Rosslyn.

To compensate for reduced rail service on the Blue Line between the Stadium-Armory and Largo Town Center stations, some rush hour Orange Line trains will run on the Blue Line.

Overall, Metro estimates that the shifted rush-hour service patterns will improve service for 110,000 riders, especially on the Orange Line in Arlington and Fairfax counties, where the so-called "Orange Crush" has plagued riders there for years.

The losers? Blue Line commuters who travel via Rosslyn. Six percent of Metrorail riders will see longer waits, the Examiner reported this spring.

The Red Line will not be affected by Rush Plus.