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Blue Line in I-395 right-of-way?

The Triangle picks up on the conversation about cutting back I-395 to Mass Ave.

Image from DC Office of Planning.

The Office of Planning has a public realm plan for the area, which includes two-way streets on New Jersey and Fourth, some narrower intersections, better landscaping along the streets, reconnected L and 3rd streets across I-395, and a Neighborhood Center plaza at 5th and K.

The Triangle wonders if cutting the freeway back would simply generate traffic through the neighborhood to the Mass Ave ramps. It's possible, but we should also remember the principles of induced demand: adding road capacity induces more traffic by encouraging driving; removing road capacity does the opposite. Removing the appeal of a through route here, especially given alternatives, would most likely reduce more traffic than it reroutes.

And I can think of a great use for a long, narrow, below-grade trench running between M and K Streets: the separate Blue Line, which I guessed might run under New Jersey Avenue. But why not save a bunch of money and build that segment where the highway now sits? Coming along M from the Convention Center station, it could tunnel under New York Avenue, break into the existing I-395 trench, stop at a station around K Street, then turn off at H Street just north of where the freeway would now begin at Massachusetts Avenue.

Plus, maybe one day the tracks could replace the freeway all the way under the Mall and down to the Navy Yard area. With many lanes south of Massachusetts, we could even keep lane or two for cars.

David Alpert is the founder of Greater Greater Washington and its board president. He worked as a Product Manager for Google for six years and has lived in the Boston, San Francisco, and New York metro areas in addition to Washington, DC. He now lives with his wife and two children in Dupont Circle. 


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A couple of comments:

Regarding using the 395 trench, I'm not sure that it would make sense for Metro. It's going to have to be underground for the rest of the time, and while running a tunnel under that ROW might make sense, I'm not sure having it surface would, only to dive back down shortly after to get over to H Street/Union Station.

Another consideration that relates to the whole M Street alignment is the Convention Center. I was perplexed when I saw the initial proposal for the New Blue line running down Mass Ave after hitting Thomas Circle. This seemed odd, since it bypasses a very important chance to share a station with the Green/Yellow line trains at the 7th St. Station. Having the new Blue line hit and transfer with all of the other lines it would cross is a must for it to be an effective line. (I would think that if it's on M Street, you might be able to do a tunnel down to Farragut North - that's only about a block)

Anyway, I think I figured out why they put the line down Mass instead of continuing down M street - the Convention Center has a huge underground portion to it. Going under it on M street would require a) going very deep, and b) would be problematic due to going under an existing (massive) structure.

An alternative would be for the line to do M street in Georgetown, continue on M until it hits Connecticut, then go up Rhode Island to Scott Circle, and proceed across on O Street. That way a convention center station would still be able to connect to the existing platform on the Green Line (which extends north from the 7th/M intersection, IIRC), turn south on New Jersey and then back East on H Street.

Anyway, for 395, if the car role were to be de-emphasized, perhaps it would be a chance to run streetcars express under the Mall and to SW DC.

by Alex B. on Jun 27, 2008 2:32 pm • linkreport

EDIT: I meant for the line to jog up to N street, not O street. Having a little trouble with the alphabet on this Friday...

by Alex B. on Jun 27, 2008 2:42 pm • linkreport

I think I might be missing some bit of understanding here, so please correct me if I'm wrong, but I don't actually think this plan is going to accomplish much. Ostensibly, the problem being addressed is that most of the traffic along NY Ave is through traffic - starting and ending outside the district. This traffic, and the wide boundary NY Ave. cuts, prevents the surrounding area from developing a better neighborhood feel.

But we already know a few things from this scenario. One is that these "suburban invaders" find the 395 to NY Ave route to be their best commuting bet. For whatever reason, they prefer it to the SE/SW to Anacostia option. Secondly, NY Ave. is capable of handling that capacity to the driver's satisfaction (though it might be a pain for locals).

Looking at the map, moving the 395 ramp a few blocks won't change either of those facts. Mass Ave. itself clearly heads in the wrong direction for most of those travelers. And a very short trip up New Jersey (5 blocks) will put them back on NY Ave where they would have been otherwise. And it will continue to have the capacity they expect. I don't think that 5 block detour (even though it'll bottleneck) is enough to get these drivers to take a drastically different route, and there's no local alternative I can see.

Side note: I think it's insane to have an Interstate just end in the middle of a city. Really really crazy. They should get rid of that entire stretch of 395 and instead route all that traffic along SE/SW to the Anacostia, and invest in running it underground so it stops killing vital urban neighborhoods. But that's just wishful thinking.

by RyanA on Jun 27, 2008 2:47 pm • linkreport

Ryan: Don't forget that the Anacostia option is bad now because there is no direct connection from the Anacostia Freeway southbound to the Southeast Freeway westbound. Despite the folly of adding freeway capacity, the administration has decided to add those ramps and widen the bridge.

An easier route that way coupled with a more difficult one around the MV Triangle would probably divert a significant amount of traffic to that other route. Even by classic traffic engineer thinking, it makes sense.

Alex: Grr, I didn't know the Convention Center went far underground.

by David Alpert on Jun 27, 2008 3:13 pm • linkreport

David: That's definitely a good point, and I'm actually surprised that in our car-crazy culture the politicians and engineers didn't connect the two freeways better, sooner. And I think that change will go a long way toward rerouting traffic and getting it off NY Ave. But do you really think the plan to shorten 395 a few blocks itself will have much of an impact?

by RyanA on Jun 27, 2008 3:25 pm • linkreport


I, too, was disappointed to learn how extensive the underground portions of the Convention Center were. They've got floor plans available online:

They mention ceiling heights of up to 30 feet, meaning even if the foundation was just a slab and you could tunnel under it (also assuming subsidence wouldn't be an issue, and it likely would be) the structure is at least 40-50 feet deep, meaning a tunnel (to say nothing of a station) would have to be lower still. That's certainly possible, but once you get out of Georgetown, I'd imagine you'd want to dig those tunnels as shallow as possible.

Anyways, I think going around on N Street (and connecting with the existing station for a transfer) would be preferable to going down Mass Ave and not having any realistic transfer, yet alone serving an area that already has Gallery Place within a short walk.

by Alex B. on Jun 27, 2008 3:53 pm • linkreport

N Street isn't very wide at all. I'd imagine they'd have to stack the tunnels like they did north of Columbia Heights. M Street is the same. I'm guessing that's a big reason why they sent it down Mass Ave.

by inlogan on Jun 27, 2008 4:09 pm • linkreport

Let's be clear: nobody has sent it anywhere. WMATA has, at various times, released vague concept sketches. Most of them included a transfer at Mount Vernon Square. Some made it look like the line would be on Mass Ave. But nothing is decided. After all, they published my map on their site, and my map definitely shows it on M (with a Thomas Circle stop and a New Jersey Ave stop as well as the transfer).

If they actually get around to engineering studies for the thing, I'm sure there will be an evaluation of various alignments and their costs, as there always is. Until then, we can speculate and discuss the pros and cons of anything, but WMATA hasn't decided and probably has absolutely no idea about most of the pros and cons of each alignment.

by David Alpert on Jun 27, 2008 4:19 pm • linkreport

@RyanA: The plan to shorten 395 should have some impact if only because the amount of traffic that can enter/exit the I-395 tunnel will be significantly reduced. The ramps at Massachusetts Ave are only 1 lane wide, not 2. This means that on the tunnel north of D St, only 1 lanes worth of traffic will be accomodated. This means that at least through traffic would be severely reduced.

Overall traffic on New York Ave, however, may not be reduced or reduced all that much. If my understanding of the induced traffic theory is correct, then the through traffic removed on NY Ave will be completely replaced with intracity traffic and traffic from/to the city. My own thinking is more economics based, and I think 1) if the connection is not made between the SE Freeway and Anacostia Freeway then the through traffic will mostly travel further to get on 395, but, in addition, over the long term some of that traffic will go away, while if the 11th St Bridge reconstruction does lead to the connection of the SE Freeway and the Anacostia Freeway then more through traffic will be displaced and on a faster time frame and 2) that some but not all of the through traffic removed will be replaced with intracity as well as traffic to/from the city.

However, I do think that if the SE Freeway is connected to the Anacostia Freeway then that would likely lead DC to not worry about accomodating through traffic on New York Ave and move towards further actions to improve NY Ave in terms of pedestrian access. (As opposed to proposals to extend the tunnel eastwards past N. Capitol St. and modify NY Ave to remove some at grade crossings)

by Mario on Jun 27, 2008 4:29 pm • linkreport

I believe the stacking on the Green Line was done not because of narrow ROW under the road, but because of the narrow easement granted for Metro there, as well as the rather sharp turn the trains have to navigate under Park Road. The ROW for N Street would be plenty wide, even if the actual roadway is not.

by Alex B. on Jun 27, 2008 4:32 pm • linkreport

The one thing I've never been able to understand is why the Silver Line is proposed to come to an end somewhere around RFK Stadium. Its a complete waste of potential transit growth.

If they could route the New Blue Line through these freeway tunnels and down towards Navy Yard, they could add capacity to the ballpark and riverfront district, and then continue the line south into Poplar Point and then on to National Harbor. Replace the current Blue Line to Largo with Silver Line trains and get more value for the additional line while also serving the growing National Harbor development and points south. It just seems to make more sense, no?

by Morie N on Jun 27, 2008 4:35 pm • linkreport


The New Blue line proposal involves a lot of new (expensive) track, as does the Silver line. That's why you don't see it extended to new places like National Harbor.

As for the current Silver Line proposal, the reason they have it stopping at Stadium-Armory is two-fold. First, that's the first place with a pocket track that would allow for trains to turn around. Second, they don't have (and won't have anytime soon) enough rail cars to extend the Silver Line all the way to either Largo or New Carrolton, much the same way that they can't yet extend the Yellow Line all the way to Greenbelt.

by Alex B. on Jun 27, 2008 4:43 pm • linkreport

How about converting the entire tunnel to transit, all the way from southwest? The green line would go straight into the tunnel from Waterfront station. You would completely separate the green line from the yellow line, effectively doubling the capacity of the yellow line bridge over the Potomac. Blue line trains could cross the bridge, freeing up space in the orange line tunnel. The tracks between Rosslyn and Pentagon might be converted into a light rail shuttle, perhaps an extension of the Columbia Street streetcar or a future light rail through Alexandria.

The amount of new tunneling would be minimal, just a rail tunnel from Waterfront to the far side of the SW expressway, and pedestrian tunnels to connect the new yellow/blue line stations with Federal Center SW, Judiciary Square, and Union Station (a longer walk but needed for commuter rail transfers). This would solve the problem of Potomac crossing capacity created by the silver line at much, much lower cost than a new blue line Potomac crossing or any other proposal that I've seen.

From the northern terminus, future extensions would be possible to the east or west, but the high cost of such extensions would obstruct the initial phase which would solve the urgent problem created by the silver line.

by tt on Jun 27, 2008 5:55 pm • linkreport

As someone who commuted from Baltimore to DC (and then moved to DC and visited Baltimore a lot) the whole 50/NY Ave/395 situation needs serious re-evaluation. It's a disaster during most of the day and especially on Friday afternoons in summer when people head to the shore. On a larger scale, traffic problems are created all over NW and NE DC because there are no good ways downtown without taking local streets. The Greenbelt Park & Ride is completely filled fairly early, so extending the Green Line up a ways to Laurel could help, but that wouldn't help people going further south on 395.

Plus, 395 has a horrible negative impact around the Capitol, where it cuts off the windswept and empty Judiciary Square area from the Hill. Could it be covered over?

by rj3 on Jun 27, 2008 8:23 pm • linkreport

Why not just have the Blue line run straight up New Jersey Ave, an have a station in Northwest One like at the corner or NJ ave & Pierce Street or at the intersection of NJ Ave & NY Ave. and make a left on M or N street. Since the area will eventually be redeveloped with lots of residents wouldnt that be a good place to station or atleast an entrance to a station in the area. I can not see anyone on New Jersey Ave walking all the way to Ny Ave station or Union station everyday to catch a train.

That area right around NY Ave & NJ Ave intersection is the farthest from any present metro station in the general area, its 6 long blocks from NY Ave station, about 3/4 of a mile from Union Station or Judicary Square and about 6 blocks from the entrance to MT Vernon Sq station and good luck crossing NY Ave anywhere between 395 and 1st street.

What i would really do is have lightrail or Metro Extra run straight down New York Ave from Bladenburg Rd to 7th Street with all the developments going on in Noma and all along New York Ave people will eventually be wanting to go up and down New York ave and the only way to really do that is by car because there is really only about 6 blocks of metro bus service on new york ave between 7th street and bladensburg rd and the rest of the ave is not accesable by bus or train.

NY ave should not be treated as a highway it is in the middle of DC, it is extremly hard to cross it, let alone the amount of traffic it has. NY starting at Bladensburg RD and going west until 7th should be treated as a regular street or avenue and not a shortcut to maryland. I think we should block 395 from NY Ave at whatever cost, cars coming off 395 treat NY Ave just as a highway and there houses, schools, school kids etc crossing it all the time, I had to have seen an accident or someone getting hit or a near hit at least 4 ot 5 times a month on somepart of it between North Capitol Street and 395 over the past 10 years

by kk on Jun 28, 2008 12:28 am • linkreport

If this were happen I'd like to see a blue line metro station at K Street with two exits. One exit at New Jersey Ave and K Street would service Northwest One. The exit at 3rd St & K St would be a few blocks closer to the Neighborhood Center Plaza at 5th & K St.

by FourthandEye on Jun 28, 2008 10:32 am • linkreport

I might vote to junk the entire underground portion of 395 and give it to whatever type of rail/transit, and create a bridge over the Anacostia from Barney Circle to the Anacostia Freeway. Make it only four lanes wide. NIMBY's will still have their freeway connection to downtown, but it will reduce the induced demand and take traffic off NY Av so it might be revitalized.

Additionally, as unfathomable as it might be, I'd like to see NY Av separated from the John Hanson Highway, which is technically an interstate highway. It's too easy to fly down an expressway (B-W Pkwy or JH Hwy) onto NY, making it feel more like a continuation of these freeways, which I believe is of greater detriment than the 395 tunnel.

by Dave Murphy on Jun 28, 2008 2:44 pm • linkreport

I heartily vote in favor!

by tom veil on Jun 30, 2008 10:54 am • linkreport

because a routing along Mass. Ave. could serve many additional riders, while a routing as you propose does not.

Note that the NY Ave. Transportation Study from a couple years ago suggests making the through portion of I-395/NY Ave. an underground tunnel.

by Richard Layman on Jun 30, 2008 2:29 pm • linkreport

Richard: if it's routed along Mass Ave, how will it get to H Street? Or do you think it should run on Mass Ave all the way through Capitol Hill instead of along H?

by David Alpert on Jun 30, 2008 2:33 pm • linkreport

Another issue with a Mass Ave route is that where do you transfer the separated blue line with Yellow/Green if not at the Mount Vernon/CC station? Isn't Gallery place maxed out? There does need to be a transfer point - I would say that is pretty much non-negotiable. Besides the Upper Mount Vernon Triangle and Northwest one will deliver the residential/office density Richard is adamant about before this line ever would arrive (2020-2030?).

by FourthandEye on Jul 3, 2008 9:02 pm • linkreport

I don't think anyone has mentioned this but the 3rd st. tunnel (395) was built to carry 8 lanes of traffic. Right now, at the northern portion of the tunnel right before NY ave, there are only 4 lanes being used, there are temporary walls built on each side of the tunnel that i believe are being used for storage right now, but they exist because the tunnel was built to carry 95 etc. Could they possibly reconfigure the northern portion of the tunnel and run tracks through it if necessary? I don't really believe that is necessary but i guess one could explore that...

by Dan on Jul 10, 2008 3:42 pm • linkreport

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