A portion of the Wiehle-Reston East Station in Fairfax County is seen during a tour in November. The station will be part of the Silver Line. (Matt McClain/The Washington Post)

By this time next year, the Washington region’s travelers will have boarded two new transit lines. Meanwhile, other important projects and programs will leverage parts of the existing transportation system to make travel easier — once the construction part is over.

All this is costly, and some transportation agencies will make travel more expensive for rail and road users.

These are the 10 developments during 2014 that are likely to have the greatest impact on travelers:

Metro’s Silver Line. The opening of the new Metrorail line between Largo Town Center in Prince George’s County and Wiehle Avenue in Fairfax County will be the top transportation story in the D.C. region and one of the biggest in the nation.

As riders begin to use the five new stations in Fairfax, the temporarily dormant debate over whether a heavy-rail line was worth the multi­billion-dollar investment will resume.

Questions about the value of the project will find a particularly sympathetic audience among Dulles Toll Road commuters, who started paying a higher toll as of Jan. 1, to support Silver Line construction, and among Metro’s Blue Line riders, whose train service was reduced to make room for the new line.

D.C. streetcar service. While the initial route on H Street/Benning Road NE is only two miles long, the start-up of streetcar service in 2014 will mark the modern debut for this type of transit service in the Washington region.

The District Department of Transportation envisions this as the beginning of a 22-mile network to be built over several decades. Like Metro’s Silver Line, the District’s streetcar program has some immediate challenges, including a federal safety review, before passengers can board. In December, one streetcar arrived for testing on the H Street tracks, just north of Union Station.

Initial experience may provide some guidance to planners in Virginia and Maryland who have their own surface-level rail projects in the works.

Metro fare increases. The transit authority staff has proposed fare increases for Metrorail and Metrobus that will be the subject of public hearings early this year. This round of increases will be more modest than the past several.

Metro’s financial planners worry that ridership (rail ridership, particularly) has become more sensitive to fare increases. Of particular concern: The federal transit benefit, a great incentive for commuters to use Metro, shrank from $245 to $130 per month as of Jan. 1.

Metro’s rebuilding program. The aggressive program of rebuilding the transit system to compensate for years of delayed maintenance will continue in 2014 at the same level riders experienced in 2013.

The best news of the year is likely to be the entry into service of the next generation of Metrorail cars, with some big improvements over the types of cars used since Metro opened in 1976.

M Street bike lane. Cyclists will start using a westbound cycle track on M Street paralleling the eastbound version on L Street NW. A one-block segment of the route between 15th and 16th streets represents a design compromise to accommodate Metropolitan AME Church, which was concerned about losing Sunday parking.

It won’t be the last time the District and other local governments need to balance the interests of different types of travelers. The built-up communities in the region’s core will place a greater emphasis on safe environments for walking and biking.

Completion of toll highways. Drivers won’t be left out in 2014. Maryland will complete the final phase of the Intercounty Connector, between Interstate 95 and Route 1 in Prince George’s. The Maryland State Highway Administration also will finish the related interchange project that created the lane shifts and rough pavement on I-95.

On the south side of the D.C. region, work will continue throughout the year on the 29-mile-long 95 Express Lanes, scheduled to open early in 2015. Construction should be less disruptive than during 2013, but travelers will hear a lot more about the lanes as program managers launch a marketing and education campaign.

11th Street Bridge. The District Department of Transportation will finish a new freeway segment above 11th Street SE near the Navy Yard. This will take traffic to the outbound 11th Street Bridge over the Anacostia River.

While that’s good for the outbound drivers, it may be even better for the inbound commuters, who will pick up an extra lane coming off the bridge heading toward downtown Washington and the 14th Street bridge. This should reduce some of the weaving and squeezing that backs up morning traffic along one of region’s major east-west commuter routes.

Rebuilding interchanges. The Maryland State Highway Administration plans to begin construction this spring on an interchange to replace the traffic-choked intersection at Georgia Avenue and Randolph Road in Montgomery County. This has been a top priority for Montgomery — and for car commuters — for many years.

Meanwhile, in Prince George’s, work will get underway around the Branch Avenue interchange with the Capital Beltway, improving traffic access to the Branch Avenue Metro station. This project, also set to be done in 2017, benefits from the new revenue available through the Maryland gas tax increase of 2013.

16th Street NW bridge. The District Department of Transportation plans to begin replacement of the 50-year-old bridge that takes 16th Street over Military Road. Rebuilding the aging structure is likely to have a big impact on traffic on this major commuter link for Maryland and D.C. drivers.

The department also plans to finish rebuilding the temporarily closed Kal­mia Road NW bridge, an important east-west link through Rock Creek Park in the northern part of the District.

Virginia highway widenings. The Virginia Department of Transportation will begin the second of its three “spot improvements” along the westbound side of Interstate 66 inside the Capital Beltway. When completed in 2015, the project will create a mile-long auxiliary road for through traffic between the Washington Boulevard on-ramp and the Dulles Airport Access Road off-ramp.

This year, VDOT also plans to open the left shoulder of the Beltway’s inner loop to through traffic at rush hours in a 1.8-mile zone between the north end of the 495 Express Lanes and the George Washington Parkway.

Both projects should ease traffic, but eventually, drivers will have to squeeze back into the existing through lanes.

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