Double Decking


A guest post from regular commenter Garlynn Woodsong:

Recently, we have discussed the testing in San Francisco of a double-decker bus, which will then move on to Las Vegas, NV to go into full service as a part of the fleet serving their Deuce line. Tri-Met is currently running its fleet on B5 biodiesel, and plans to ramp up the percentage of biodiesel in the mix as more supplies become available from local production. Tri-Met is also currently testing/running some hybrid-electric buses on some of its lines.

What I’d like to cover in this post is the possibility of introducing hybrid, double-decked buses to Tri-Met’s fleet. Apparently, London has already ordered them, and they will enter revenue service there in a couple of years.

Not only would they provide additional capacity per driver, they would have lower emissions — hybrid buses generally tend to post about 30% lower emissions (or 30% better fuel economy, if you prefer), resulting in a 15% decrease in operating cost. Combining this with the lower operating cost per rider of a double-decker bus, and some real money-saving could be possible! Running such a bus on biodiesel would further reduce its emissions.

There could also be more room for bikes, using hooks inside the bus. Some new low-floor, double-decker buses (such as this one) have as many as 78 seats on the two-door model, with 31 downstairs and 47 upstairs. It might be possible to not only put a 2-bike rack on the front of such a bus, but also include MAX-style vertical bicycle hooks on the inside of the vehicle for a few more bicycles by removing seats/taking multiple advantage of the wheelchair area (making it into a more flex-space zone to accommodate either wheelchairs, bicycles, luggage or standees, depending on conditions — with of course wheelchairs always having the option to pre-empt any other use).

Clearance, however, would be an issue. Not every route would be eligible for a double-decker bus. A hybrid double-decker bus is likely to be between 13.5 and 14.5 feet in height. With a vertical clearance of only 13 feet, the Broadway Bridge would thus be off-limits to such buses. With a vertical clearance of 15.7 feet, however, the Hawthorne Bridge would be fair game!!

Introducing such buses on the 14-Hawthorne might therefore be feasible — though, of course, we would only want to see this as an interim step on the way to a streetcar line on that particular route — right Bob R? Similarly, double-decker buses would likely be feasible for routes such as the 20 and the 12 that cross the Burnside and other bridges with no vertical clearance issues. Some vertical clearance issues might present themselves due to low overhanging trees on some routes, especially near bus stops that don’t have curb extensions, but these would need to be evaluated on a route-by-route basis.

Certainly, Vancouver, B.C. is another West Coast city that is running double-decker buses successfully, as a way to cost-efficiently add capacity on their trunkline routes running radially out from their downtown.

Some drivers from Hong Kong have reported hauling crush loads of over 200 people on double-decker buses in service in that city. I remember riding the 19-Woodstock, years ago when it was served by the 200-series buses, and the driver declared that our run regularly had over 100 people at the height of its crush load. This suggests that it is possible to almost double the capacity of the bus by adding a second level and going double-decker — which is amazing, when you account for the space lost by the stairwell! (Granted, folks in Hong Kong are likely to be slightly smaller than folks in Portland, so we might never see 200 people actually fitting into a crush load on a bus here, unless it was on a bus serving an after-school run…)

As Tri-Met searches for ways to squeeze more capacity out of its limited operational budget, I suggest that running double-decker buses might be a way to achieve the goal of more passengers per driver. Articulated buses are not likely to make a re-appearance in Portland, and not every bus route that has capacity issues can be converted to a streetcar line. For those lines that don’t have vertical clearance issues, going double-decker would seem to be a worthwhile proposition. And as the technology becomes more widely available to do so, it would make sense for these double-decker buses, like all new buses that Tri-Met orders, to also be hybrid-electric (like the 800 new series-hybrid buses that New York City has ordered, featured in this article).

Photos:

Wright Eclipse Gemini Double-decker bus

Wright Bus most similar to an Electrocity, the hybrid-electric double-decker bus currently being tested in London


27 responses to “Double Decking”

  1. we would only want to see this as an interim step on the way to a streetcar line on that particular route — right Bob R?

    I will not be so easily goaded into a fight, I promise! :-)

  2. I like the idea, at least on a trial basis. Line 14 or 15 would seem a good place to start. Or maybe a new route: would there be any merit to interlining 14-Hawthorne and 15-Northwest Portland with double-decker buses?

  3. Certainly would be useful at some hours of the day, although overall I rarely see even the 4 or 14 full enough to justify another layer — would the added cost and reduced efficiency of a heavier bus be justified at current ridership rates?

    Also, would there be issues with overhead wires on those streets? I don’t imagine that would be too tough to fix, but I’m wondering if double decker buses are a plug-n-play solution or not.

    Finally, “running such a bus on biodiesel would further reduce its emissions”? Emissions of what, exactly? Biodiesel still releases carbon dioxide into the city’s air like regular diesel.

  4. BioDiesel generally has fewer harmful non-carbon emissions, especially particulate emissions, than regular Diesel.

    And, depending on how the source material is grown/utilized/recycled/processed, there can be a net decrease in the overall carbon life-cycle.

    – Bob R.

  5. Bob R, just making sure. I agree with your first paragraph, though I’m dubious about the applicability of your second. Either way, carbon dioxide EMISSIONS remain about the same, right?

  6. How peculiar! I just had the same thought this week myself. As a Brit who’s been living in Portland for just over two years now, it never occured to me until this week that not a single one of Portland’s buses are double decker! In England, almost all buses are, and it increases capacity no end. They are also very fun to ride, because you get such a unique view of your city that you will never find in another vehicle (expect perhaps a flying carpet!)

  7. I think this is actually a good idea. They should double deck the Amtrak Cascades, too and while they’re at it, double deck all the freeway and major arterials throughout town.

  8. “And, depending on how the source material is grown/utilized/recycled/processed, there can be a net decrease in the overall carbon life-cycle.”

    Depending, yes. Don’t get me wrong, old french fry oil is great, and a little canola isn’t bad either, (a lot of canola is just as bad as a lot of corn,) but the marginal bio-diesel on the planet right now comes from palm oil, which is grown by slashing&burning rain forest in third world countries. Besides the fact that destroying the rain forest isn’t very good for things that happened to be living there, when you add up all the GHG emissions from turning rain forest into cropland, it releases on the order 30 times more GHGs than just burning regular old diesel…

    So I’m not exactly in a big hurry to use a bunch more bio-diesel. If TriMet wanted to be innovative, they could convert a bus to run on Wood Gas. (Long startup times aren’t a big deal for a bus, unlike the way most people use cars.)

  9. I think biofuels are the future and that we can grow enough for fuel and food. Just driving through the valley you’ll find not much useful farming except for many thousands of acres of grass for lawn seed, nurseries and wineries. All three of these industries aren’t really necessary unlike food and fuel production.

  10. Either way, carbon dioxide EMISSIONS remain about the same, right?

    At the tailpipe, yes. Also, see Matthew’s comments above about how the wrong source for biofuels (as is apparently the case for much of the BioDiesel today) can have an overall negative impact.

    Perhaps the greatest achievements in the 21st century won’t be merely technological, but will instead be the development and widespread use of modeling tools which can tell us the full dimension of real impacts of a particular technology.

  11. How much clearance is there beneath the MAX and Streetcar overhead wires?

    The specification for a Siemens SD660 (TriMet Type III LRV) is an operating height of between 13.0 and 22.3 feet.

  12. Articulated buses are not likely to make a re-appearance in Portland

    I’m not so sure of that.

    Articulated and double-decker busses each have their own pros and cons. There are some streets in Portland that are likely not appropriate for an articulated bus (i.e. many streets in near-Southeast); however these streets also have vertical height restrictions that need to be addressed prior to introducting double-deck busses – anything from low-hanging utility wires, trees in the right-of-way, or older span-wire mounted traffic signals.

    Articulated busses require relatively smooth, wide streets but in some cases are easier to manuever on curves. They do require larger bus stops which may not be easily constructed in the older, developed neighborhoods (especially where parking is at a premium, and the idea of removing more parking spaces to make way for a larger bus stop might be controversial).

    In short – double-deckers might make sense on the routes like the 4, 14, 15, and 19.

    Articulateds make more sense on routes like the 12, 33, 57 and 72.

    TriMet did run the 700s on the old 88 line which used a lot of narrow two-lane roads from the Sunset Highway to the Intel Aloha campus (and Washington County roads were – and in many cases still are – notorious for being narrow and not having any type of a shoulder). I’ve personally ridden the 700s on Skyline Road (a detour due to construction on the Sunset Highway). And many TriMet operators liked running the 700s.

    And don’t forget that Portland did have a double-deck transit vehicle in operation for many years recently:

    http://www.trainweb.org/oerhs/roster/blackpool_48.htm

    The Oregon Electric Railway Historical Society owns one other double-deck tram, a Hong Kong narrow-gauge car:

    http://www.trainweb.org/oerhs/roster/hongkong_12.htm

  13. Might there be nuisance problems with kids being as loud, rowdy and obnoxious on double-decker buses as they often are on MAX trains? I’m wondering what would happen once kids go from the still-visible back seats of current buses to the out-of-sight, out-of-earshot upper deck.

    Also, do double-deckers need to spend more time at each stop waiting for someone on the upper deck to walk to the stairs, come down, and exit; and waiting for a new passenger to walk back, go up the stairs, and sit down?

  14. “You mean, replace the Talgos with “California Cars”?”

    Those things have a top speed of 79 mph. The Talgos are faster, (assuming the track can support it.) There are dual level cars that support higher speeds, the TGV has some, but…

    “How much clearance is there beneath the MAX and Streetcar overhead wires?”

    I want to say the signs I’ve seen (on the transit mall where they are doing construction and need to avoid hitting it with equipment) say 15 feet…

  15. Well, they actually have double decker trains that go from Portland to Seattle and back, except that route’s called the Coast Starlight. It’s slower by half an hour and has significantly fewer amenities (no movie, no power outlet at your seat, shakier, has that “some guy was sitting here for a full day” smell). It should be noted, there isn’t seating on the lower deck, just more storage.

    I’m not aware if the Sounder-style trains (which appear to be actual double-deckers) are suitable for longer routes like cascades.

  16. Also, do double-deckers need to spend more time at each stop waiting for someone on the upper deck to walk to the stairs, come down, and exit; and waiting for a new passenger to walk back, go up the stairs, and sit down?

    I never noticed this in London. Most people went up and down the stairs while the bus was in motion.

  17. Yeah, I’ve been on double-decker buses in Edinburgh, and there’s no more or less latency — if you’re at the door when they stop, you get off. Otherwise, the bus moves on. This is just as true on TriMet buses — I’ve seen plenty of people who decided not to get up until the bus had stopped and didn’t make it to the door in time.

    I do think that security would be an issue on the top deck late at night. Given what I’ve seen happen (at the back) on single-deck buses in the evening, I can only imagine what people think they could get away with when the driver’s out of sight. (And yes, security cameras would probably be installed, but the cameras on current buses didn’t stop those people from “secretly” drinking their hooch and whatnot.)

  18. A better way to increase capacity would be to add more buses, particularly to the overcrowded lines. This would shorten wait times and make getting around more convenient, thereby attracting more riders (like me). Many of these riders would be people who are not currently being attracted out of their cars because of the huge difference in public transit travel time versus auto travel time (for me, downtown in 12 minutes by car versus 38 by bus). These are also the people Trimet needs to win over to continue to improve service and expand the system.

    In manufacturing, the Japanese system of Just In Time (Toyota, et al) has proven it far more efficient to make smaller quantities on a continuous basis than larger batches more infrequently. If anything we should have buses half the current size which run twice as often.

    Once buses run at less than 10 minute intervals and they’re all full, then it will be time to start talking about more capacity per bus.

  19. Todd, I would be inclined to agree with you, to the extent to which we can afford to double the number of drivers and buses.

  20. The cost of providing transit service isn’t so much in the size of the bus as the salaries and benefits of the drivers. We get more bang for the buck by increasing seats per bus (guaranteeing more people seats at peak hours) than by increasing the number of buses on the road — even though higher frequency would do more to improve ridership.

  21. Well, they actually have double decker trains that go from Portland to Seattle and back, except that route’s called the Coast Starlight. It’s slower by half an hour and has significantly fewer amenities (no movie, no power outlet at your seat, shakier, has that “some guy was sitting here for a full day” smell). It should be noted, there isn’t seating on the lower deck, just more storage.

    I’m not aware if the Sounder-style trains (which appear to be actual double-deckers) are suitable for longer routes like cascades.

    Whether an Amtrak Superliner car is a “true double-deck or not”, well, it is. There is a fully functioning lower level, save for the area at either end of the car where the trucks are – those areas hold mechanical equipment (such as HVAC equipment and electrical closets) that on a conventional railcar would be slung underneath the car, or would be in closets in the main level of the car and therefore reduce usable space for passengers.

    The Bombardier bi-level commute service cars are less of a “true double-deck” car, because each end of the car is single level, with stairs leading up and down to each level in the middle of the car.

    Colorado Railcar (the makers of TriMet’s DMU for WES) purports to make a “true” bi-level commuter car in competition with Bombardier, but they have only made a handful of the cars (all for South Florida RTA) and have received no new orders from other transit agencies. They have made a number of bi-level cars for several tourist operations in Canada and in Alaska, however.

    As for why the Superliners aren’t as fast as the Talgos – it’s because they weren’t designed for high speed operation above 90 MPH. Both the Japanese and French high speed rail systems have bi-level coaches. There is no reason in the U.S. to design a car with a higher top speed, because there is no rail that would support the use of such a car at such a speed – Superliners cannot operate on the Northeast Corridor because of the catenary height.

    And, personal preference matter – I can’t stand the movies on Amtrak Cascades. I take the train to look out the window; if I wanted to watch a movie, I’d fly the Horizon Shuttle, and then watch a movie at a downtown Seattle movie theater.

  22. The cost of providing transit service isn’t so much in the size of the bus as the salaries and benefits of the drivers.

    This is a very valid point, one that is often cited as a “benefit” of light rail transport.

    A 30′, 40′, or 60′ bus all has the same labor cost per bus; the bus driver costs the same per hour regardless of the size of the bus. (Yes, TriMet used to pay a differential for driving an articulated but that isn’t required unless per the Union contract, and isn’t a drawback of articulated busses in general.) It’s possible to have smaller busses operate at a lower cost (i.e. cutaway busses, like TriMet’s “Local” busses that operated on the MAX feeders and some of the local routes, particularly out of Oregon City and Clackamas Town Center TCs), if the Union will allow. Seattle does this very successfully as do many California transit agencies. TriMet, I believe, cannot do this.

    However, three articulated busses running at 20 minute intervals provides a slight increase in seats over four 40′ busses running at 15 minute intervals. That means that the articulated busses provide a 25% labor cost savings but no decrease in capacity/service. A double-decker bus would, of course, provide the same or extremely similar results.

    On high capacity routes where supply is already exceeding demand, it would make perfect sense to simply increase capacity by adding articulated busses, rather than reducing headways to 10 minutes. Increasing “frequent service” from 15 minute headways (requiring four busses per hour) to 10 minute headways (requiring six busses per hour) is a 50% increase in labor and fuel cost.

    Increasing headways is certainly a viable option if the ridership can support it. However it would seem more prudent to increase capacity without the expense of hiring more operators. TriMet already needs to replace nearly one-half of its bus fleet. Replacing even 100 of these busses with articulated busses, rather than 40′ busses, would provide an immediate increase in capacity without increasing any other expense for TriMet. By purchasing hybrid electric busses, it would actually reduce fuel consumption at the same time – while the federal government will pick up 100% of the cost differential between the diesel bus and the hybrid-electric bus.

  23. Not that other people haven’t figured this out, but what do transit agencies do about the potential for crime/unwanted behavior on the upper deck of the bus?

  24. Not that other people haven’t figured this out, but what do transit agencies do about the potential for crime/unwanted behavior on the upper deck of the bus?

    I fail to see why this is even coming up as a question. If this were a problem, then EVERY MAX TRAIN WOULD BE A SINGLE CAR TRAIN.

    A double-decker bus has a security ADVANTAGE over a MAX train – if there is a problem, the bus driver can simply pull over, get out of his seat, and walk upstairs – the stairs are usually right behind the driver’s seat.

    A MAX operator, if summoned to an emergency in the rear car, would have to stop at the station, get out of the cab, get out of the car, and walk back to the second car. A MAX car is just over 90 feet long, plus about 15 feet from the front of the second car to the first door.

    If the station platform is congested, it is that much longer for a MAX operator to get to the rear car to assess the emergency.

    Meanwhile, he has to make sure that he secures the cab by removing the controller handle and taking his keys with him – before he can exit the cab.

    Not to say that it is a frequent situation, but the double-decker bus (or an articulated bus) has a security advantage over a two-car MAX train.

    If necessary, a closed circuit TV camera and monitor could be installed on the bus so that the bus operator could monitor anything upstairs. (Yes, this is possible on MAX too, except that it requires a connection between the cars. What happens when a crime happens and someone is trying to rely on the communications system, but someone in the yard forgot to connect the two together (or someone went inbetween the cars at Hatfield/Gresham/Expo Center and intentionally disconnected the camera connector)?

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