Arlington County officials have approved a slew of improvements -- roughly $33 million worth -- in an effort to radically revamp the aging Rosslyn Metro Station.

Northern Virginia's busiest Metro stop serves roughly 36,000 riders a day during the workweek. Arlington officials say that number will balloon 25 percent to 45,000 by 2030, meaning one of the area's oldest stations needs a makeover.

"There aren't many stations in the [Virginia] system where there are two Metro lines that intersect. So it's a major transit hub and it was badly in need of these improvements," said Arlington Board Chairman Jay Fisette.

The county, after more than a year of work alongside Metro officials, plans to install three new high-speed, high-capacity elevators, as well as an additional stairwell.

The renovations also include a new mezzanine, fare gatesand a connecting passageway, which the county's planning staff says will improve "commuter flow."

"This will effectively be a completely new station entrance," said Arlington and Metro board member Chris Zimmerman. "It will facilitate more people moving in and out more efficiently."

Arlington officials said they had hoped the station improvements would coincide with other private developments planned for downtown Rosslyn.

Real estate owners JBG and Monday Properties have major projects planned near the station, although both developments have been sidelined because of problems securing financing in the struggling economy.

"We hoped all the development would occur simultaneously," Fisette said, although he expressed optimism that at least one of the projects would break ground this fall. Both have received approval from the Arlington County Board.

Zimmerman echoed Fisette's statement, but added it was better to get the new station built ahead of the new commuter traffic.

"We're hoping to have the capacity improvements there when the people arrive, as opposed to the other way around," he said.

The county will use roughly $20 million in federal and state grants to cover a big chunk of the station renovations, and are scheduled to begin work on the improvements this fall. The project is expected to take three years to complete.