All forms of transportation can be characterized in two dimensions. The first, accessibility is a measure how easily it is to join and leave that particular facility. The second dimension is speed of travel on that facility. These two dimensions are inversely related. As accessibility increases speed decreases and vice versa. Streets are a perfect everyday examples. Local streets are slow but offer very high accessibility, while freeways have very low accessibility but very high speed.

So how accessible is LINK for pedestrians compared to other mass transit systems in the Northwest? Well, not very, especially compared to Portland. Station spacing is an important measure of how dense of a network a transit system has. The ideal station spacing for pedestrian access and continuous linear TOD is roughly two times what an average pedestrian would walk, so roughly ~.5 mile to ~1 mile. Now look again. Magically MAX and Skytrain fall into that range. Both the Expo and Millenium lines hover perfectly in the range, while MAX jumps around a bit more because of variation in land use patterns and geography. So, coincidence or planning?

Northwest Mass Transit Systems
Northwest Mass Transit Spacing

So what happened to LINK, why is it so off the mark? Well for starters we have weird geography which has forced our growth pattern into a long and narrow shape. This necessitates a long central line of ~55 miles, Everett to Tacoma. This length forces planners to reduce accessibility to increase speed to a competitive level. In comparison the 2nd longest line is MAX’s Blue line at 33 miles. Another double whammy is money. Sound Transit is a three county regional transit provider who’s mission is to build a regional transit system. Subarea equity has forced Sound Transit to build out rather than fill in Seattle proper with highly accessible mass transit. Yet another reason is that we are late to the game. MAX and Skytrain were built to influence growth patters. They were design to maximize accessibility, area coverage, and TOD opportunities. Now LINK is trying to follow growth not shape it.

So before I close I do want to point out one jem in the ruff, East LINK. After removing the distance inured by Lake Washington, East LINK looks like it will be the poster child of the entire system when it comes to walkable, TOD communities. It is hovering just above the walkable range, and because of the S shape of the probable alignment these distances are actually much shorter. In addition to that the City of Bellevue has made Seattle’s zoning department look childish in its attempt to up-zone station areas.

Below the fold is another graph showing how LINK, Skytrain and MAX stacks up against mass transit systems around the world.

Mass Transit Systems Worldwide
Mass Transit Systems Worldwide

65 Replies to “LINK Station Spacing”

  1. We pretty much know what we are getting in ST2
    We assume that ST3 will include the following
    * North Link to Everett
    * South Link to Tacoma
    * East Link to Redmond
    * East Link to Issiquah
    * Central Link to West Seattle
    * Central Link to Ballard
    * Upgrades to Sounder
    * More Buss service
    Could ST3 or ST4 also include additional stations between some of the existing stations?
    If so where would you put them?
    how many new stations would be needed to go below the 1 mile average?
    the .5 mile average?
    How would the re-addition of the Boeing Access Road station affect Central Links numbers?

    Lor Scara

    1. If you add aditional stations, do you add an aditional class of train?
      Locals hit every stop, Expresses hit every 3rd stop
      If so where do you add the extra “Passing tracks”

      1. If memory serves me correctly, there are 2 lanes of traffic at each stop in the buss tunnel.
        The inside lanes could be used for Passing, you could set it up so that a “Local” was serving the platform, while an “Express” was passing the local on the inside lane. (This wold probably take more track work in the tunnels, but would not (theoretically) require a major modification to the tunnel structure.

        runnerodb83 is correct that the tunnel would serve the major destinations in ST1, in ST2, it may make sence to have one out of 4 or 5 coming from the north end, act as an express through DT,and head over to Miocrosoft, making no DT stops.

        Lor Scara

      2. Without changing any of the station or tunnel structure, you would need to install new switches at each end of the station to both directions’ tracks, new signals and control systems, and new overhead catenary. There might not be enough space at those ends to accommodate the switches and clearance for the train. Any larger changes would be too disruptive to the existing system in operation. Trains passing through stations will probably be limited to 10-15 mph for safety reasons, as they are now.

      3. Lor Scara,

        The issue of passing is not in the bus tunnel. EVERY train will stop at EVERY station in the CBD. There’s no need for “express” service there. Central Link would need “express” service only along MLK and north of Roosevelt. The tunnel between Capitol Hill and the UW Stadium passes under single family homes and is WAY too deep to make it worthwhile to intermix stations. Ditto the section through Beacon Hill. The elevated stretch along the freeways south of Boeing Field passes through such sparsely developed and inaccessible land, it won’t need stations either. However, it was a mistake to cancel the Marginal Way station. There are still a few homes in the area but more importantly, it offers close access to the Boeing facility.

        Basically Link is a bit of a hybrid, which has resulted in the longer station spacing than is normal for LRT. In fact, Link is a regional rapid system, NOT a light rail system. It just happens to use LRT technology so that it can run down the middle of MLK and alongside the busway from Lander to Royal Brougham. Because people are expected to ride from as far away as Federal Way, and perhaps eventually even Tacoma, the stations cannot be closely spaced.

        I think the way to separate the two functions is to build a single-track “express” connector alongside the railroad lines between Boeing Access Road and Argo yard, under Airport Way and north above Sixth South to the flying junctions at the maintenance facility. This would remove five station stops and probably would cost only a couple of hundred million, since the right of way is already graded.

        Now the BN and UP might not be happy about losing the car storage that taking a track would require, but some sort of compensation could be made.

    2. Don’t forget that stops have been cut from the original proposal in order to retain the veneer of voter ‘accountability’.

      I was quite active in that era of the debate and with the support of former Councilmember Jim Street we were able to successfully get a design which served the denser neighborhoods of Seattle enroute to the suburbs, on the north alignment.

      This same argument was used successfully by Councilmember Martha Choe(most recently Gary Locke’s CED Director) in gaining Rainier Valley service, to be followed by Roger Pence advocating for a Beacon Hill tunnel.

      Perhaps the most aggregious of these Station cuts was the second University District Station – definitely more important than the Roosevelt stop. That would be a battle worth fighting, but not alone.

  2. Because ST is trying to make a regional system using light rail, usually reserved for heavy rail (SF BART for example), as well as a local one on the same system. I wish you would have put SF Muni on this list (which is light rail) as it would have been a good example of a regional (BART) and local (Muni) system separated. DC Metro is interesting because it is heavy rail exactly like BART; however, they’ve used it as you would light rail in the core by placing stations closer together. That is pretty much what we’ve done here (though why we don’t have a station at Madison still boggles my mind), except we’ve used light rail. Had we a station at Madison like we should, central link would look more like all the other systems you showed.
    Using light rail will probably cost us more as we will need more drivers since the trains are smaller…but, that also means we will have a train more often, which sounds sweet to me. But that is a different conversation.

    1. By “a station at Madison” do you mean between Westlake and Capitol Hill? The First Hill station was prohibitively expensive and forced the line into a weird shape (though it still doubles back a little instead of simply following Pine Street).

      I’d have liked to put a station somewhere between Cap Hill (perhaps renamed Broadway or SCCC?) and University of Washington, and another at Maple Leaf (about 1.8 miles between Roosevelt and Northgate?), but the post makes a good point that we’re kind of forced to use Link for more regional purposes.

      1. While I agree more stations are often better, in Capitol Hill it would be very expensive to have another station particularly because the soil is so moist. Ric, the ST planner, said as much at a recent Friends of Seattle event.

      2. Well yes politicians make the choices but that isn’t so say that they are immune from the realities of construction and risk costs. To say it is all politics is to over simplify such a complex issue.

      3. Coming from a person on the inside of the UW Link Project, soil conditions, the 4.8% grade up Capitol Hill, and the curve made it impossible to have a station. The station itself was to be built on a complex spiral curve (curvature changes vertically and horizontally within the curve itself). The other place where it was thought to put a station is between the stub tunnel curve and the curve up to Capitol Hill Station. But the tangent (straight) section is only 100′ long, which is barley enough for one LRV. Sadly, the First Hill Station will never be.

        Building a station between UW and CHS wouldn’t be smart since the underground stations cost a few hundred million each, there wouldn’t be any density where the station would go, and UWS is rather close. Another problem is that the tunnels are deep under ground on a grade when it travels between the north edge of the hill and the Montlake Cut. The line is taking a 4.11% dive from CHS to the Mountlake Cut! The tunnels will go under the intersection of Garfield St and Aubrun PL then go straight down 20th and McGraw St. (about 60′ below ground on a 4.11% grade) where it will curve to UWS.

      4. So the track will climb an almost 5% grade after leaving downtown and then plummet back down almost as quickly to go under the Montlake Cut. The track at UW will end up below sea level so they have to start climbing again immediately to daylight and go back up to Roosevelt which is going to be how much of a grade? Quite the roller coaster ride.

      5. Thank the UW for this move. Its costing a few hundred million dollars and 3 extra minutes to not go down 15th and take this route instead. They were worried the train’s vibrations would upset the instruments in the physics building. Now, ignore that the bus hub for the UW is at the DOOR STEP of the physics building. And we STILL have to mitigate train vibrations in the ground with a crazy elaborate system I can’t discuss!

        BTW, CHS to Westlake is 4.99% southbound (downhill), 4.88% northbound (uphill) and UW TO CHS is 4.11% on both tracks. The tracks will be about 30 feet below sea level in UWS.

      6. Maybe UW should have asked for money to build a physics lab. The existing building is nothing to write home about anyway. Benoroya Hall was built on top of the BNSF tunnel.

        Now the UW is look at asking for compensation because during construction fans may stay away from football and basketball games. Never mind the fact that when completed out of town fans will be able to ride from the airport straight to the stadium on the light rail. That’s probably the real reason they wanted it moved. The football program has more clout than the physics department.

      7. I thought there were also some rather serious problems with tunneling under portage bay which caused the alignment to move from 15th. In fact I believe this is why the initial segment didn’t start at 45th and why link is opening now rather than back in 2005.

      8. According to the North Link EIS (page 6-15, last paragraph) the Montlake route actually has the highest vibration/EMF impacts, while the routes on the west side of campus had the least. The current route was chosen in spite of vibration, not because of it.

        Chris is right about the tunneling risk. The EIS pages 6-12 and 6-13 go over this in detail—the ship canal is a better place to cross due to a shorter crossing and better soil, so it ends up being cheaper than most of the Portage Bay plans (Figure S-5, page ES-31).

        Also, the Husky Stadium station is singled out as having particularly high ridership due to being next to the med center (middle of page 6-8).

      9. I can’t say the specifics why (think vibration mitigation!), but it is far more costly to dig the current alignment. And the current chosen route is longer as the route straight up 15th (longer tunnel = more expensive). There are a lot more politics involved than you may thing. Its not always “soil conditions” ;-)

      10. There were a lot of moving parts to the fiasco that was the 15th NE/Portage Bay alignment.

        One factor certainly was the soil conditions under Portage Bay. This forced the tunnel depth to be much greater than originally planned and would have made the station at 45th deeper than Beacon Hill.

        Another factor was the $800 million bid for the tunneling contract on the 15th/Portage Bay alignment and the near collapse of the agency in its wake.

        The UW was a factor too, since with the deeper tunnel ST needed more co-operation with the UW. This put the UW in more of a position to impose its own demands on ST.

      11. Where exactly is this route headed? I know where Garfiled is, but Auburn Pl? Do you mean arboretum? There is a giant valley between garfiled and 20th and Mcgraw as well, called Boyer and the steep hill of Interlaken. it seems like under 23rd, a major arterial would make the most sense. I have a relative with a house in this area of Montlake, which is not a cheap or noisy area (yet).

        I sure hope the vibration mitigation works. 60′ is not that deep for a light-rail train. If you ask me, this whole thing is idiotic beyond words. Why is the train not just going up the express lanes? with stops that more or less correspond to 39th, 45th, 65th etc. Because the tunnelling mafia need their payoff.
        Busses between the UW and downtown are doing the job fine…

      12. Buses between downtown and the UW are not doing the job just fine. The buses are at crush loads for much of the day, 7 days a week. The buses are stuck in traffic. The schedule reliability is poor due to high passenger loads and congestion.

        Funny thing is even with the cost of the tunnel U-Link and North Link received one of the highest cost-effectiveness scores ever from the FTA. Why is that? Because the ridership of U-link and North Link is huge.

      13. U Link is one of those places where the train will beat buses or cars any time of day. There are already too many vehicles on the roads in the U-District (which is why it’s insane to add any more bridges from 520 but that’s another topic). If they didn’t need to pick up Capitol Hill I’d say an above ground route following Lake Onion and then crossing the University Bridge (it used to have rail) would have worked but Capitol Hill is a huge ridership area in it’s own right.

        I know the roller coaster route selected ended up being more expensive than the one supposedly nixed by the UW physics dept but I think having the station down by the hospital and Husky Stadium will prove to be the best location.

        The bus tunnel seemed like an expensive folly at the time. Over the years though people start to see it as a bargain. The worst thing about Link is now we need to dig another bus tunnel! (only partially kidding)

      14. Actually the whole North link alignment from Northgate to Downtown has great ridership and will beat either buses or cars for much of the day. Even many rail transit critics feel downtown to Northgate via Capitol Hill and the U-District is a good use of rail transit. It doesn’t hurt that there really isn’t a sane or affordable way to widen I-5 in that corridor.

        There were huge problems with the soils under Portage Bay which had as much to do with killing the 15th NE alignment as the UW’s objections. As I recall the bid received for tunnel construction on the original alignment was well above estimates and may be above the current estimates for tunnel construction for U-Link even without adjusting for inflation.

        I will agree things worked out for the best. The station at the stadium is a better location than NE 15th & Pacific for all the reasons you state as well as it’s proximity to the Montlake freeway station. I also feel the station between 43rd NE and 45th NE on Brooklyn is a much better location than the Burke Museum parking lot would have been.

        I’d forgotten about all of the critics who considered the bus tunnel with “all that expensive tile” to be a waste of money. In hindsight it did turn out to be rather a bargain.

        One lesson from the bus tunnel construction that should be remembered for Link is the long-term impact it had on the businesses along the route. Street level retail still hasn’t fully recovered along 3rd. The cut & cover construction along Pine combined with some other factors caused a “hollowing out” of the retail core that required massive investment to correct in the 90’s.

      15. Does anyone know why there won’t be a Link station at the end of the stub (near the existing Convention Place/Paramount bus tunnel station)? If my memory serves me correctly, it seems the track is relatively straight at the end of the stub and won’t have too dramatic a grade.

        I got excited last week when I saw some construction going on around the stub ventilation shaft. But I am quite sure there is no plan for a Light Rail station at this location. (I live near Convention Place and I wouldn’t have as far a walk down to Westlake or up to Broadway if there was a station at the current Convention Place Bus Tunnel location)

    2. Actually, heavy rail metro technology is more commonly built and restricted to the central city, whereas light-rail or EMU technology is more typically used for suburban service, particularly in Europe and Asia. Driverless systems are comparatively rare, are very expensive, and actually make more sense in systems that have a very high ridership, necessitating very low headways – ie, metros.

      BART and Skytrain are kind of anomalies in their application of technology and the service they supply, but do reflect a North-American style metro area. Germany’s U-Bahn/S-Bahn systems, which are fairly standard across the entire country, make good case studies. Munich in particular. Note that often the suburban and urban systems share tracks in the city center to allow transfers, as well as to serve the CBD.

  3. I like this post. except to say that we were forced to build a suburban spacing because of geography is just not true. We made a conscious political decision not to build separate suburban and urban systems, and to focus on extending as far into the suburbs with rail as possible in order to capture a larger taxing district. We could have built an urban system here with a more constrained taxing district, as they did in both Vancouver and Portland (with state/provincial help), but that was not what worked here politically.

  4. Great post, Adam. The data has convinced me that the Rainer Valley could use another station in a future light rail plan.

    1. I read that LINK is really Light Rapid Transit not Light Rail like MAX, which is probably why the stations are spaced further apart. Also, it is more Grade Separated than MAX.

      As for another Station in Ranier Valley, wasn’t there supposed to be one near Orcas or Graham St, but it was dropped?

      1. Graham would make sense. It might eventually be an infill station. Infill stations do get built. When I was in Washington D.C. in 2007, I saw one station on the Red Line, the next one beyond Union Station, around New York Ave that looked different than the others, turns out it was recently built, probably to take pressure off of the two stations on the other side of it, and based on traffic demand.

  5. All I will say is that after living in Japan and coming home to Portland, I felt that MAX was embarrassingly slow. A lot of this was station spacing and at-grade tracks in downtown. You can easily have 1.5-3 mi (or 3-5 km!) station spacing but concentrate commercial and dense housing near the stations.

    Half a mile is about a 10 minute walk which is why New Urbanists say 1/4 to 1/2 mile radius is the optimal size of a neighborhood. That’s where you do all your everyday things. If you need to go to the airport, see a game, etc., you hop on the fast mass transit system.

    1. I don’t know portland all that well, but every time I’ve been on that beast, I’ve thought about how slow it is. It reminds me much more of SF’s Muni light rail than a rapid transit system.

  6. Adam,
    You asked what I would add as possibilities for a next phase:

    1) A station near S 133rd Street (Gateway Station).

    2) To increase the speed for passengers south of the airport, I’d like to see an express track between the area near Boeing Access Road and SODO Station with one stop somewhere around Boeing and the Flight Museum.

    3) Start a cross town between West Seattle, Burien, Southcenter and Renton. This could replace Sound Transit’s Route 560 and use those buses for more I-405 service between Bellevue and the Kent Valley. The connection between West Seattle and downtown could wait for a future phase if Rapid Ride works adequately. This could provide a transfer to the north-south line at S 154th Street.

    1. Good ideas, especially for the express track. The travel time from the south is going to be slower than express buses, so putting in some express trains would make it a lot more attractive from, say, Redondo or Highline stations to Seattle. Otherwise you will get some people riding because it is a train not a bus, but many people will just stick on the bus.

    2. A line from West Seattle to downtown would have far more riders and be much more successful than a line from West Seattle to Renton. It should be below grade the whole way, as it sounds from the various studies like it is impossible to link up tracks with the West Seattle Freeway and there’s various turning radius problems at the Harbor Island bridge.

      1. Actually, someone at the meetup on Wednesday—it might have been Geoff Patrick—was saying that the grade of the West Seattle Bridge is doable with the current light rail cars, in addition to there being space available on on either side of the bridge if needed.

      2. Well then that makes it a lot easier and removes having to tunnel under the Duwamish and have a hella deep tunnel under West Seattle. It should go over the West Seattle Bridge then into a portal when the bridge hits West Seattle and turns south. Then just do the monorail route, with future extensions to Burien via White Center.

      3. If West Seattle gets Link I doubt it will get a tunnel except maybe right in the junction area.

        Elevated or elevated/at-grade is far more likely.

    3. One of the groups proposing a vision for a cleaned up Duwamish had some Light Rail lines in there, including one that went down Airport Way and then turned over to go up Roxbury. I doubt if that is possible, but look into it anyway.

      As for a Gateway Station in Tukwilla, should be looked into as well, currently too wide of a gap between Henderson Street and S. 154th Street Station. I would go one better, and un-defer the Boeing Access Road Station, complete with it being the interchange point between SOUNDER and LINK it was supposed to be.

      1. Huh well in my opinion their light rail route idea kinda sucks, cause it looks like it’s trying to avoid South Park and a few other major areas. But I really like their idea for a water taxi down the Duwamish. The stop placement should be changed around a bit, but otherwise, that could be quite successful, especially if they have it go down to the spot where its just about one or two blocks away from where the Boeing Access Road Station would be.

  7. Being also a heavy rail (or better newer technologies) fan who favors geographically constrained revitalization of small towns around the state and country, I wonder if some of the distances between stations in the burbs allows us to have open space? Or, is that just all gone like in Northern Virgina.

    I realize Light Rail going through the city is going through populated areas, but I think the stretcars and even buses make up for more stations.

    I’d just hate to see the equivalent of a new road being built with new development all along it because of too many stations.

    I already agree I might be ignorant here.

    1. Sorry, Concerned, but going North-South, the Seattle Metropolitan Area is essentially built out with burbs from Fort Lewis in the south to Arlington in the north. Other than “postage stamp” size greenspaces in between, you would not see too much open space. (With one noted exception being the agricultural lands in the floodplain northeast of Everett, and the reservation directly north of Everett.)

      Going east you still have some actual greenspace between Issaquah and Snoqualmie/North Bend, but that is about it for built-out suburban areas…

  8. It’s extremely important that Link be seen more as a traditional metro or subway than as a standard light rail system, as then it will get way more riders going the long distances from the suburbs to downtown and around Seattle. Instead of adding a million more stations to Link, we should build a huge streetcar system all around the city and the denser parts of the suburbs to get people to Link. Like someone said, this should be like Muni and BART, with BART for long distances, and the Muni for getting around in town.

    1. If that were possible, I would use a comination of streetcars and trolleybuses in Seattle based on what we had with the Seattle Municipal Street Railway. Bellevue, Redmond, and some other communities don’t have that kind of map to fall back on, unfortunately. Taacoma and Everett are the only streetcar cities that have any experience, although maybe Issaquah’s on again off again streetcar might be worth looking into being a future connection with an expanded LINK.

  9. Nice post. One minor quibble: the Canada line is not Skytrain as it doesn’t use Bombardier’s ALRT and it is unclear whether it will be branded the same as Skytrain.

    1. I believe the reason that they cannot call it SkyTrain is that it has nothing in common with the technology used in SkyTrain, mainly the Linear Induction Motor, because that is proprietary technology for Bombardier, but I am suprised the Province of Ontario does not have control of the patents, they developed it.

      Now I saw a PDF of the Canada Line’s vehicles from Rotem Hyundai’s website, and there it showed the hostlers controls, ostensibly for emergencies, as it will be driverless. Although during the storms of December, no Translink Rail line whether it was the Expo or Millenium line, was driverless. Attendents were at the manual controls.

      I like the idea of trains that have drivers, even if ATC and other devices make them redundant. It’s the safety factor.

      1. If I recall correctly, there haven’t been any accidents on SkyTrain due to the automation, so it’s hard to argue that it’s not safe enough without human drivers.

  10. Maybe I’m missing it but the statistics for the London Tube seem to be missing. I come up with 249miles/270stations=.9 miles between stations. I know the Tube serves more than downtown London but this is one of the largest cities in the world so station distance for Link in the 1-1.5 mile range seem perfectly reasonable. Obviously some areas are going to be a lot closer together and some farther apart. Shortest distance on the Tube is only 1/10 of a mile; barely over 200 feet. But then some of their stations are today seeing ridership approaching what we are forecasting for entire system ridership in 2030!

      1. About 300 feet in length. By comparison, the Stockholm Metro runs 460′ trains – very typical for a higher capacity metro system.

      1. I also notice London is missing from the list. What kind of textbook would omit London?

      2. I have no idea why it wasn’t included. It did seem strange to me as well. My guess is that it would be somewhere around 1 mile spacing.

      3. Could it be that many lines in London extend out into the suburbs with very long spacings, making the average meaningless? Unless they did one just for stations within the central area.

      4. Lines from London extend not only to the suburbs but to Scotland and France. No hard science or figures here but my mum grew up in London and her take is the goal of the Tube system was that you could get anywhere in the city with two rides. Seemed to work when we visited last a few years ago. You don’t worry about transfers because there’s always a train. Like the Horizon Air commercial, you’re not late for one flight, just early for the next.

        My take on this is that a rail system is dependent on bus transfers being in place that will fill that second seat.

  11. I’m a Chicago resident and from glancing at the ST2 plan, the station spacing on Sounder Commuter rail seems much more out of proportion when compared with Metra or Caltrain.

    1. The spacing is largely dictated by geography. Especially on the North line there just aren’t many additional opportunities for stations.

      For the South line there is a combination of wanting to keep reasonable end to end travel times, plus the problem of putting in parking that limits the station count somewhat.

Comments are closed.