Metro’s board of directors approved adding more buses on high ridership corridors in the region and expanding service on some routes between Crystal City and Rosslyn.

The changes are an attempt to address the No. 1 complaint about Metrobus: Service runs late.

For $2.3 million, the transit authority is going to add more buses and adjust schedules to reflect “traffic reality,” said Dan Stessel, Metro’s chief spokesman, on its priority corridor bus routes. Some of the priority corridor routes have had poor performance because of traffic congestion, Metro said.

The changes will go into effect in June on bus routes in these areas, including Naylor Road to Potomac Park, Pennsylvania Avenue, Wisconsin Avenue, 16th Street NW, Georgia Avenue, Southwest waterfront, Leesburg Pike and New Carrollton to Silver Spring.

Jim Hamre, director of bus operations planning, said the routes are “below our standard of performance.”

“By putting in some additional run time we hope to improve reliability,” he said.

Changes to bus routes and run times are only made four times a year.

“This is an opportunity to adjust running times to reflect changes in traffic patterns,” Hamre said. “It will improve reliability because we’ll now have sufficient time to operate the bus along the route. People will see it show up on time, more often and the impact of traffic congestion will be less variable.”

The money to pay for the changes to the priority bus corridors comes from a $5 million surplus in Metro’s fiscal 2011 budget. Metro General Manager Richard Sarles said there was a surplus after Metro paid off a “preventative maintenance loan” and did an audit.

He said Metro wanted to implement the changes sooner rather than wait for next year’s 2013 fiscal budget.

The Metro board also approved adding bus service to lines in Crystal City and Rosslyn to try to help alleviate the impact of its “Rush+” service, where the number of trains on the Blue Line will change to accommodate future service on the Dulles rail extension and to relieve crowding on the Orange Line.

Starting June 18, Metro plans to operate six additional trains per hour — three in each direction — between Vienna and Largo Town Center. The move will also increase the number of Yellow and Green Line trains, Metro said.

But not every rider will see an upside.

About 16,000 weekday rush-hour customers between Pentagon and Rosslyn on the Blue Line will have to wait six minutes longer for a train.

By adding additional bus lines in Crystal City and Rosslyn, Metro said it hopes to give riders another option.

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