The Silver Line is already changing the way people will travel around Northern Virginia.

Not due to open until next year, the new Metro line nonetheless has transit planners busy remapping many of the biggest bus routes in Fairfax County.

The proposed changes to Metrobus and Fairfax Connector lines are intended to make the Silver Line a nexus for public transportation around Tysons Corner, which will be home to four of the Silver Line’s first five stations.

Many of the changes, including adjustments to 11 Metrobus routes, would take effect at about the time the rail line opens in December 2013. But the Fairfax County Department of Transportation is starting earlier. Some new Connector routes to Tysons will begin in January in an effort to jump-start bus ridership ahead of the Silver Line’s launch.

For some users, the changes will mean shorter bus rides to Metrorail. For example, residents in the Reston and Herndon areas who now take buses to the West Falls Church station instead will be able to take buses to the new Wiehle-Reston East Station.

“People’s travel patterns will change,” said Julie Hershorn, Metro’s manager of bus planning.

Primarily a commercial destination, Tysons is projected to grow dramatically after the Silver Line opens. The county predicts that the population of Tysons, now at about 17,000, will grow to 100,000, and officials and developers hope to transform Tysons into a walkable community where people live, work, shop and play.

Metro does not plan to add bus routes to the area but expects to discontinue service on a few bus routes, which will be covered by the increased Fairfax Connector service.

“We have been working very closely with Fairfax County to coordinate Connector routes, Metrobus routes and Silver Line service to make sure that we have good coverage in the whole Tysons Corner area,” Hershorn said.

Eventually, the $5.6 billion Silver Line project will extend Metro to Dulles International Airport and into Loudoun County. But for now the focus is on Fairfax, where the first phase of the line will run through Tysons to Reston.

The county is launching three express bus routes early next year that will connect southern Fairfax to Tysons. A bus line will bring riders from the Burke Centre Virginia Railway Express station to key locations in Tysons starting in January. Routes from Springfield and Lorton will start in March, county transportation officials said.

These new bus lines mark the beginning of increased bus service to the Silver Line corridor, said Christin Wegener, chief of the Fairfax Connector Section.

In total, the Fairfax Connector plans 12 new routes and adjustments to 17 others. In Tysons, a new circulator service will make stops at the four Metrorail stations, Wegener said.

Fairfax, like many jurisdictions in the region, has seen increasing demand for bus service. Fairfax Connector recordednearly 11 million rides last year. With construction of the first phase of the Dulles Metrorail project now 76 percent complete, local transportation officials said that now is the time to boost travel options and start the shift to transit commuting in the corridor.

“We have to increase capacity,” said Fairfax Supervisor Catherine Hudgins, who chairs the Metro board of directors. “As Tysons continues to develop, the increase of transit service really will contribute to the improvement of Tysons and all of those stations and areas along the new rail line.”

Metro has scheduled a public hearing next month to discuss proposed changes to the Northern Virginia lines, which are part of a larger package of Metrobus adjustments the transit system wants to make next year to address ridership growth, crowding, and bus performance.

Fairfax plans to unveil a Web site this month with details on the proposed new routes, route adjustments and the Tysons Circulator, which would start the day the Silver Line opens.

“This will provide new travel options for folks who want to ride a bus to Metrorail and for folks who are new to transit, who never used the bus system before but have been waiting for the rail service,” said Nick Perfili, the county’s Dulles Metrorail project planner.