View of Tyson's Corner Metro Station with Tyson Tower under construction behind it. (Jeffrey MacMillan)

Dear Dr. Gridlock:

I continue to wonder whether the Silver Line will be less of a success than planned — or too much of a success.

As regards the former possibility, I think much will depend on whether there are frequent buses to take people from the train to their destinations. People don’t like to walk very far.

If, on the other hand, the Silver Line is a big success, the route of the Orange, Blue and Silver lines from Rosslyn through downtown is going to become impossibly crowded.

At some point, the question will arise about adding a third track to the route, or whether a new line must be built across downtown.

— Peter Bridges, Arlington

Bridges looks at the Silver Line as a two-way transit route, and that’s exactly what Metro and Fairfax County will be promoting.

It’s partly about encouraging ridership. Lynn Bowersox, the Metro official leading the marketing of the new Silver Line, has noted that ridership estimates for the Silver Line are a few years old. She couples this with a warning that the estimates assumed widespread knowledge of the Silver Line’s existence, which at the moment does not appear to exist.

Her mission is to change this, and it won’t be the first time Bowersox has marketed a train. As an Amtrak executive earlier in her career, she helped publicize the Downeaster train service between Portland, Maine, and Boston.

The line, which started in late 2001, can be used as a commuter route to Boston from the far suburbs. But the business and civic leaders in Maine who promoted the line’s creation weren’t just looking for a way to send workers to another state.

They wanted people to ride the other way, too — and not simply because they bought a roundtrip ticket from Portland. They wanted to promote Maine as a destination.

In fact, the line was expanded in 2012 to add more stops in Maine. Here’s how the Downeaster’s Web site promotes one of them: “The Freeport train platform is just steps away from hundreds of national retailers, name-brand outlets, and locally-owned boutiques all set in a 19th century Maine village.”

That’s Freeport, as in L.L Bean.

Transportation planning isn’t just about the journey. It’s also about the destination. From the point of view of transit operators, they’re giving people places to go, which will increase ridership. From the point of view of local leaders, they’re opening communities to more shoppers, diners and workers.

These are the strategies that Bowersox and leaders in Fairfax County are pursuing. And this is why the Silver Line will never be mainly a way to reach Dulles International Airport, even after the line’s second phase opens and air travelers have that rail link.

The bus plans that Metro and Fairfax County are making for the new stations aren’t just about getting commuters to and from the stations. They’re also about getting people to destinations in Reston and Tysons. Meanwhile, Metro has begun selling those local attractions to people across the entire Washington region.

The worst problem they’ve got won’t come till phase two: How to persuade air travelers to use an inconveniently located station at Dulles International Airport.

Meanwhile, one thing I don’t believe will be a problem — at least not in the early going — is the second issue raised by Bridges in his letter: Won’t all the inbound commuters cause congestion between Rosslyn and downtown Washington?

No, that’s the easy part, when compared with the challenge of generating outbound riders to Tysons and Reston. Riders at the stations from East Falls Church through Stadium-Armory will see the same number of trains they have today. There’s no reason the platforms or trains should be any more crowded once the Silver Line starts.

A decade from now, we’ll need a new track around the train bottleneck at Rosslyn.

Dr. Gridlock also appears Thursday in Local Living. Comments and questions are welcome and may be used in a column, along with the writer’s name and home community. Write Dr. Gridlock at The Washington Post, 1150 15th St. NW, Washington, D.C. 20071 or e-mail