MARC Train. Image from J.H.Gray on Flickr

Washington, DC is blessed to have Metro – a great urban transit system.  It’s probably the single best thing to happen to the city in the past 50 years – and even more notable considering the era it came from.  When most cities were depopulating and building freeways instead of transitways, DC built a subway system.  Several cities built subway lines, but DC managed to build an entire system.  Given the dominance of the automobile both in public policy and in public perception during this era, this accomplishment is nothing short of remarkable.

However, the success of Metro can sometimes hamstring future transit discussion in the region.  If people want transit, they want it to be Metro.  Even if Metro (specifically – heavy rail rapid transit – fully grade separated) isn’t the best option for the job.  Rapid transit lines are tremendously expensive and must have high ridership to justify their expense.  Still, when people talk about expanding transit in the DC region (which is good!) they tend to focus on simply extending Metro lines places.  Plenty of folks point out the oddity of putting the most expensive mode of transit out on the fringe – especially when some of those places (Orange line to Manassas, Blue Line in NoVA) already have existing commuter rail connections.

Some of that stems from the hybrid nature of Metro.  Unlike her sister system in the Bay Area, Metro at least functions as a more traditional subway within the core of DC.  However, out on the fringe, the rail speeds, station spacing, parking supply, and distances covered function much more like a commuter rail system than a subway.  Thus, it’s somewhat natural for people in the region to associate a commuter rail trip with Metro’s brand – but that doesn’t make it the best choice of mode.

The solution seems blindingly obvious – many of the corridors mentioned for Metro extension, whether that’s the Orange line to Manassas, the Blue line to Ft. Belvoir, or the Green line to BWI – are already served by commuter rail.  The issue is that commuter rail service in the DC region is sub-par.   MARC and VRE simply don’t have the good brand name that Metro does, and for good reason – the service they offer is inferior.

Plenty of people have opined about future commuter rail service in DC, including both MARC and VRE themselves. I won’t bother to re-hash what are essentially obvious arguments – bring MARC and VRE under one brand, increase headways, increase hours of operation, essentially make these services more like transit rather than just commuter rail.   Similar services in other places, whether being German S-Bahn services or even New York City’s commuter railroads show how these modes can both serve as express transit services as well as reliable transit.

The genesis of this post was simply a couple of things that came up during the past week.  First, BeyondDC made a few predictions on the state of the DC region in 2040.  The one observation that struck me concerned a future second intercity rail station in the area:

Intercity Travel:
Union Station will be past capacity and we will need a second depot, possibly in Arlington. There will be multiple trains per day running several short-distance intercity rail trips to all other population centers in the mid-Atlantic region. Camden Station will become more important in Baltimore. Dulles and BWI airports will continue to expand. National Airport may be sold and the land redeveloped, or it may continue to operate, depending on how much intercity travel continues to be done by plane.

The potential for a second major rail station in Arlington is intriguing.  It also dovetails nicely with this guest post on the transport politic about the future of regional and commuter rail in New York City.  The post harps on one key principle for New York, also applicable to DC – through-routing of trains:

The New York metro area has many stub-end terminals—Flatbush Avenue, Grand Central, Hoboken, Long Island City, St. George—as well as one station, Penn Station, which is a through-station by layout but a terminal by use, except by Amtrak. Such a configuration works in getting people to take commuter rail from the suburbs to Manhattan, but is inherently limited for all other functions…

Manhattan acts as a barrier to transportation, both by auto and by rail. By train, one needs to transfer. By car, one needs to cross jammed roads and pay multiple tolls. Through-running is a way of breaking this barrier by enabling people to live in North Jersey and work in Queens and Brooklyn, Long Island, or Connecticut, and vice versa. Though some people live on one side of Manhattan and work on another today, the current stub-end use of Penn Station lengthens those commuters’ travel time and restricts their number.

Worse, the stub-end layout reduces track capacity. A rapid transit train can dwell at a through station for under a minute, even if it is crush-loaded with passengers trying to enter or exit. At a terminal, the minimum dwell is about five minutes, and mainline trains discharging all or most passengers at the terminal typically dwell more. This clogs the tracks, leading to the absurd situation that while the RER’s central transfer point, Châtelet-Les Halles, serves 500,000 daily passengers on 6 tracks, Penn Station strains to serve 300,000 riders on 21 tracks.

Both MARC and VRE want to route trains through Union Station to serve regional destinations.   For MARC, the obvious choice would be serving employment centers at L’Enfant Plaza, Crystal City, and Alexandria directly.  For VRE, the same principle applies to Silver Spring and even through to Fort Meade and Baltimore.

Combine those ideas with the notion of both expanding regional and intercity rail service, and such routing options could increase the effective capacity of Union Station’s lower level through-tracks, as well as probably create demand for expanded facilities in the DC region.  The potential for inter city from points south (Richmond, Charlotte, Atlanta) terminating at an Arlington station is an interesting idea, creating a situation akin to Boston’s North and South Station – but with the needed track connector between them.  Likewise, Philadelphia’s through-routing regional rail shows the potential advantages of such a system.

This new terminal could easily fit on the land between National Airport and Crystal City.  The potential for connections between rail and air service is also interesting.  The location would provide an adjacent ‘downtown’ with Crystal City, but also a very short trip into Downtown DC via the Yellow line.

Both of these concepts – through routing and provisions for a new major terminal in Arlington – should be included in any future plans.