On free transfers

There is a Tweet going around that Baker’s MBTA bill has language that would allow the T eliminate free transfers. This is bad policy for a variety of reasons, disproportionately impacts the poor, disabled and elderly and would run counter to industry best practices. More on that another time. For now, here is the specific language in case you want to contact your legislator.

Current statute contains the following (Chapter 161A, Section 5, Subsection (r)):

To adopt, and revise as appropriate, a fare policy which addresses fare levels, including discounts, fare equity and a fare structure, including, but limited to, fare media and passes. Said fare policy shall include a system for free or substantially price-reduced transfer privileges.

And Governor Baker’s Bill (here) would replace that language with:

[T]o adopt a fare policy that balances the operational needs of the authority, the extent to which the authority’s fare recovery ratio is consistent with those of peer systems, the objective of increasing ridership and maximizing total fare revenues and the needs of its riders, including those of lesser means.

Much more on what the role of government is (to maximize revenue or to provide necessary services?) another time. But this is bad policy, and should not be implemented or put in to law.

Jim Stergios is bad at math

Update: It turns out, the Pioneer Institute as a whole is bad at math.

Jim Stergios, of the Koch-funded Pioneer Institute (edit: NOT the author of the discredited absenteeism report; my apologies to them for that insinuation, it’s only that, you know, Baker ran the Pioneer Institute, and the report was used by his commission had similar issues to other Pioneer reports), uses a lot of numbers to try to set up his arguments in response to a piece by Jim Aloisi. The problem? He uses numbers which are very convenient for him, ignoring longer trends which make his argument far, far more flimsy, and in many cases, completely refuted. He starts with an agenda, he warps data to make it fit that agenda. The problem is, the data tell a much, much different story.

• First, he references that in 2011 and 2012, 8 million commuter rail passengers were inconvenienced by late or delayed trains. That’s a big number. 8 million! But he doesn’t have a denominator. A big number without a denominator is meaningless (which was what most of the hubbub about the absenteeism report was about.) How many trips are there, annually, on the T’s commuter rail? If it’s 16 million, that’s a lot of delays. If it’s 80 million, it’s not quite as much. The answer? In 2011 and 2012, there were about 75,000,000 trips on Commuter Rail. So 8 million represents about 10%. Could this number be improved? Certainly. But without a denominator, this is a scare tactic: a number with no context. He claims that this resulted in a loss of ridership and revenue. But without any other years to compare it to (Were delays better or worse in 2006? He doesn’t say.), those claims are specious, at best.

(Vertical lines show locations of system expansions.)

• Then there’s this:

Notwithstanding the fact that the MBTA added more commuter track miles than other major transit systems in the country over the past 25 years, quickly raised fares and continued substandard service led, remarkably, to a decline of 13 percent in commuter rail ridership from 2003 to 2013.

Can you spot the incongruity there? Stergios assails the T’s expansion over 25 years, but is only concerned about it’s ridership over 10. It turns out that before 2003, the T was the fastest-growing commuter rail system in the country. If you look at the period from 1988 to 2013, T commuter rail ridership more than doubled. Even if you exclude extensions, at stations open in 1988 and 2013, it grew 65%. I made the argument that T ridership is hampered by high fares, and stand by that conjecture. In fact, for trips between 18 and 27 miles, the T has the highest fares of any commuter rail system in the country (this will be explored in depth in a later post).

It’s almost as if the investment in commuter rail in the 1980s and 1990s paid dividends in ridership during that time. But for an institute that wants to cut investment in transit, those data are very inconvenient. So they choose to ignore them. Thus, his data are misleading at best, and borderline fraudulent at worst.

• So he’s stepped in it already, but then he links to an article from his policy “research” institute that allows him to step in it some more. That article goes to great lengths about how, between 2003 and 2013, the T was the only major commuter rail system to lose ridership. You know what, I can’t argue with that. During that time period, the T did lose ridership, while other agencies gained. Again, I contend that it’s due to fare policy, but we each have our ideas why. But notice how he again very conveniently picks 2003 as his start date, which was the highest ridership on record. By doing so without showing any other data, he suggests that the T has underperformed other commuter rail networks. Let’s see if that is actually the case.

Annual ridership for SEPTA, Metra, MBTA

The two most similar commuter rail networks—with multiple legacy lines feeding the city center—are SEPTA in Philadelphia and Metra in Chicago. They also (conveniently for me, this time) have ridership data back as far as 1980. (Here’s SEPTA, here’s Metra, which I estimated from a chart but is exact enough for this post. Unlike Pioneer I don’t obscure my data sources; all MBTA data came from the Blue Books available on the T’s web site.) And, yes, the MBTA has had stagnant ridership in recent years, while SEPTA and Metra have both trended upwards. (This is also the case with New York’s commuter railroads, as well as Caltrain and MARC.) So there is certainly a case to be made that the MBTA’s commuter rail networks has been a laggard in recent years. This is likely due to a variety of factors, including stagnant service levels (SEPTA has, in recent years, been adding service), increasing fares (both Metra and SEPTA have lower fares per mile) and equipment and trackage which has been allowed to fall in to disrepair (SEPTA has invested heavily in their physical plant recently, and Metra runs on freight lines which have kept their tracks in good working order).

But the chart above is only one way to look at these data. Another is to normalize everything by an arbitrary year. I used 1988 (left), because Stergios likes to look back that far (sometimes). But for fun, I also made a chart that goes back to 1979 (right), because that’s the first year I have data from for all three systems.

Feel free to click to enlarge. The 1988 chart shows how, in the past 25 years, ridership on the MBTA Commuter Rail system has far outpaced SEPTA or Metra, growing by more than double while the others grew at a much slower rate. Go back to 1979, and the T has more than quadrupled, while, after falling off in the early 1980s, Metra and SEPTA only recently surpassed gas crisis ridership levels. In fact, if you look back to most any year but 2003, you get a very different picture. But, again, Pioneer’s “research” is picking and choosing numbers to fit their narrative, but not to show what actually happened.

• But wait, there’s more. He also claims that the MBTA has added more commuter track than any other system in the country in the past 25 years. Here he’s not fudging numbers, he’s just plain wrong. The T operates 394 miles of commuter rail. Metrolink, in Los Angeles, operates 388 miles. However, Metrolink began operation in 1992 which—let me get out my abacus, carry the 2—is only 23 years ago. So in the past 23 years they’ve added 388 miles. I’m not sure to the decimal of the amount the T has added (it’s about 145 miles over that time, of which at least 20 is in, and paid for by, Rhode Island) but it is certainly less than 388; even in 1988 the T operated more than, say, a shuttle from North Station to West Medford.

• Stergios also references his bus maintenance study, but that study borderlines on laughable, and may also be the subject of a separate post. Of several data irregularities there, the most glaring are the comparisons that the Pioneer Institute draws from the most comparable bus systems. For example, the list of most comparable bus systems to the T’s includes many systems in warm climates with low living expenses and ridership 1/10th of the T. Are we surprised that the transit authority in El Paso or San Bernardino has lower costs?

They make a major comparison to MetroTransit in the Twin Cities, an agency that also maintains buses in a colder climate. But nowhere in the report do the point out that while they have the same number of buses, the T carries twice as many passengers, and therefore, twice as many passengers per bus. This means that the T runs many more buses at or over capacity. A bus crammed with 75 passengers on board carries about 30% of its total weight in passengers, putting much more stress on not just the motor, but the air bags, axles, struts, tires and other equipment. (Imagine loading a Toyota Corolla with five 180 pound people and 500 pounds more in the trunk and a roof box. That’s what the T asks much of it’s fleet to do several times per day.) Many of the T’s bus routes run at this capacity on a daily basis. Only a few MetroTransit routes do, and often over longer distances. For instance, the MetroTransit Route 5 has comparable ridership to the T’s #1 bus, but its route is three times longer, meaning that the bus is not full nearly as often.

It is opaque as to how the Pioneer Institute chose other comparable agencies, but they often talk about the 79 other “large” agencies. However, the T is one of the top 10 agencies, and comparing it to an agency with as many passengers a day in total as the #1, #39 and #66 buses carry makes no sense. Is there a correlation between bus maintenance costs and overall ridership? They don’t bother to find out, and continue with these false, apples-to-oranges comparisons. The only comparable agencies in their database of the 20 most-similar systems are WMATA in DC and Muni in San Francisco (and even this is not apples-to-apples; WMATA carries fewer passengers per bus while San Francisco has no winter weather). Those agencies’ costs perfectly bracket the T’s maintenance costs per mile: the T is $3.80, WMATA is $3.20 and Muni $4.40. Compared to those agencies, the T is about where it should be.

Stergios claims that if the T operated with the efficiency of the average of these “comparable agencies” it would save $40 million a year or more. But if it operated with the efficiency of the agency in San Francisco? The T would actually spend more money. This whole study comes apart if you pull any one of many loose threads. That it is even in the discussion shows how picking only very particular data can make pretty much any point. What’s sad is that the legislature and governor bought it hook, line and sinker.

• There’s the stuff that’s just plain wrong. He claims that:

MBTA Board of Directors inexplicably authorized $47 million to purchase the Pittsfield-to-Connecticut Housatonic line

Really? The T is buying rail lines in Berkshire County? That sounds a lot like a MassDOT project, and indeed it is. They’re related, certainly, but that’s not money coming from the T’s pot. This is just careless.

WGBH fancies itself a news organization, and, as such, should have a fact checking department. Most of Stergios’s article does not pass even the slightest sniff test. GBH should be ashamed for publishing this article full of half truths at best, and several outright lies. As for Stergios and the Pioneer Institute? Anything that comes from them is immediately suspect, and usually, when examined, mostly false. They should crawl back in to their hole until they can present data with a straight face.

The golden age of American railroading was in the Upper Midwest

In a factually-inaccurate-and-not-yet-corrected post, Michael Tomansky heard an anecdote (the Beatles made it from New York to DC in 2:15) and reported it as fact, claiming that it represented a golden age of American railroads which we will never see again. It most certainly is not: the GG1s the Pennsylvania Railroad rain in the 1960s were only capable of 100 mph as a top speed, and would have had to average 100 mph to get from New York to DC in that time (it’s quite nicely 225 miles in 2.25 hours). Scheduled times never fell below 3:30. 2:15? It didn’t happen. By the late ’60s, the Metroliners were running up to 125 mph on the corridor, with trains making stops clocking in at 3 hours and nonstops running in 2:30 once a day—it turns out it makes sense to stop in Philadelphia and Baltimore. Acela Express trains now make the trip in 2:45 making six stops; speed improvements could conceivably get this to 2:30, or to 2:15 non-stop (which is unlikely as intermediate stops cost only a few minutes and account for a lot of ridership).

But the fact of the matter is that before the Metroliners, there were very few trains that eclipsed 60 mph average speeds. Many streamliners of the ’40s and ’50s ran between 55 and 60, and a few, notably the Twentieth Century Limited and one of the Pennsylvania’s New York-DC runs, broke the 60 mph barrier. (The site linked has decent schedule information; easier than combing through the 1000-plus page Guide to the Railroads.)

The notable exception to this is not a single train, but a competitive market: from the late 1930s through the early 1960s, three separate railroads ran five trains per day between Chicago and Saint Paul at damn near—and in one case, over—70 miles per hour over a distance of over 400 miles, with several stops. (It was another half hour, after a long stop and at slower speeds, to the trains’ termini in Minneapolis.) In fact, for two decades between the beginning of World War II and the opening of the Shinkansen, they were likely the three fastest rail trips over 200 miles in the world. Here a good primer on the competition and the Chicago-Minneapolis schedule from 1952:

9:00-2:30, Morning Zephyr, 431 miles, 66 mph (in 1940: 6 hours, 72 mph)
10:30-6:05, Morning Hiawatha, 410 miles, 58 mph
1:00-7:15, Afternoon Hiawatha, 410 miles, 66, mph
3:00-9:15, Twin Cities 400, 409 miles, 65 mph
4:00-10:15, Afternoon Zephyr, 431 miles, 69 mph

There were several other trains, including overnight options, each day, and these five schedules which could get you between the Twin Cities and Chicago in barely the time it takes to drive today (without traffic). Today’s Empire Builder runs the route in 7:45, at a respectable 55 mph, but nowhere near the 70+ of yesteryear (between some stations, the trains averaged over 80 mph, stop to stop; runnings speeds well over 100 were not uncommon). So while railroad speeds have slowly increased on the East Coast, it’s the rest of the country that has seen speeds come down: in particular, the Twin Cities to Chicago market.

Why did this route have faster speeds than anywhere else? Part of it is geography. Each line had its advantages, but none had many tight curves or long grades, and there were few intermediate stops to slow the trains. But part of it is competition: not with car or air travel, but with each other. Nowhere else was there a similar three-way competition over this distance. Once one railroad established the 6-hours-or-so benchmark in the mid-30s, the others quickly followed suit, and it proved to be good business. They kept the speeds in to the 1950s, when regulations bogged down the railroads, and subsidies flooded road and airport construction; the trains slowly disappeared in the 1960s. Today’s Empire Builder follows several different pieces of the former roads.

In another country, there never would have been three trains plying the same route. French railroads were nationalized in the 1930s, and Germany and Japan’s railroads were decimated during the war and rebuilt afterwards. If American railroads had been similarly nationalized or had the same sort of investment, there’s a chance that the three competing railroads could have combined resources to build a single, higher-speed line: all had rolling stock capable of over 100 mph, so five or perhaps even four hour trips would have been possible even without electrification. However, after the war American railroads did not see government investment (we certainly spent more money rebuilding railroads in Europe than we did in the US) and without a time advantage over airliners or interstates, trains that averaged near 70 mph, and except for one line on the East Coast, haven’t come back.

Bridge costs and subsidies

Driving east on Route 2 today (carpooling!) we crossed through the Route 2 construction zone over 128. The 60-or-so-year-old bridge is decaying and is being fully rebuilt. 

Average daily traffic: 104,000, give or take.
Length of the bridge: 340 feet.
Cost: $50 million.
Cost per linear foot: $147,000
Cost per linear foot per person*: $1.18
(* assumes 1.2 passengers per car)

A bit closer to the city, there’s another bridge which whisks commuters in and out of Boston every day. It’s twice as old as the Route 2 bridge, and carries more people (but fewer vehicles). I speak, of course, of the Longfellow.

Average daily traffic: 130,000, give or take (20,000 cars, 100,000 Red Line, 10,000 bikes & peds)
Length of the bridge: 1850 feet.
Cost: $255 million.
Cost per linear foot: $138,000
Cost per linear foot per person*: $1.04

From Andy Singer.

The Longfellow Bridge, which is in a dense urban environment (harder to access with materials), over water (necessitating floating in many materials), includes significant historic elements (so it can’t be replaced with an off-the-shelf box-girder design), and is longer and higher than the Route 2 bridge, is actually cheaper to rebuild overall, and even moreso when you factor in the number of daily users. Sure, you could get five Route 2 bridges for the cost of one Longfellow, but those five bridges, end to end, wouldn’t reach across the Charles. So when we talk about transit subsidies versus highway subsidies, we should remember that, at least in this case, it’s cheaper to rebuild a multi-modal bridge than one used just by cars.

I’m not saying that we shouldn’t rebuild the Route 2 bridge. We can’t let our infrastructure crumble. But when it comes to rebuilding infrastructure, it’s important to know that every time you see cones on the side of the road, there’s a real cost involved. I would not be surprised if there are a lot of people who look at the Longfellow as a bloated project—a quarter billion dollars!—and don’t give a second thought driving by the orange barrels on Route 2.

Yet if we measure return on investment by how much new bridge we get per person traveling on it, it’s the little bridge replacement project out in Lexington that costs us more. And while the Longfellow is one of only a few transit-centric replacement projects (and even it contains a majority asphalt), there are scores of bridge replacement projects across the Commonwealth that chew up a lot more money. No one ever blinks an eye at a proposal to rebuild a decaying highway bridge. That’s necessary maintenance. But more transit projects are a much harder sell, even if they’re more efficient.

The problems with autonomous vehicles in cities

When I hear about how autonomous vehicles are the panacea for urban traffic woes, I’ve been skeptical. With every apparent advance—like the recently reported hand signal patent—I come back to the fact that they apparently still don’t work in the rain (it hasn’t rained much in Mountain View recently) and certainly not snow. And they’ve driven 700,000 miles, but mostly on the same subset of suburban roads that have been meticulously mapped, not new and varied roads across a variety of terrain and regions.

But I see the main issue is that autonomous vehicles will be unable to interact with people in the same way that people driving cars can. There’s a turn in Central Square in Cambridge from Mass Ave to Pearl Street (I happen to live a few blocks away) that’s a good example. It is right by a subway entrance and major bus stop, so there are tons of pedestrians. It has a couple of crosswalks but no signals. To make the turn, you often have to wait until pedestrians “screen” oncoming traffic, worm your way left, and find a gap in the pedestrian traffic to slowly get on to Pearl Street. Everyone is okay with this if it’s done at a slow speed—if you waited until conditions were perfect, you’d never make the turn. But by the letter of the law, none of this is legal. To make the left, you would have to wait until there is no oncoming traffic (rare), whether there are people in the crosswalk or not. Then to cross the crosswalk, you have to wait until there are no pedestrians within 10 feet of the crosswalk, a situation which might occur here once every 45 minutes. (It should be noted that crosswalk laws vary slightly from state to state, so rules would have to be coded differently for each jurisdiction.)

People driving cars can get through this intersection. But an autonomous car can’t be coded to break laws. If (more likely, when) it was involved in an accident, the code would be subject to discovery, and examined at length. If anything was found that permitted the car to break a traffic law, it would be legal ammunition to go after the deep-pocketed developers. In cities, everyone fudges the law a bit for things to work. Pedestrians step off near-if-not-in the crosswalk. Cyclists nudge over the line and leave a light a few seconds early. Cars slowly make turns when they don’t have right of way and pedestrians break stride so the cars can get through. It’s not perfect, but works. Sort of.

So, take a look at the picture to the right. In the middle, note that there is a person waiting at a crosswalk. An autonomous vehicle would see this person and stop to let them cross the street. But they would just stand there. The person might flick their hand, but the car won’t easily be able to interpret that as “oh, I’m waiting, go ahead.” Which puts the autonomous vehicle—or its coders—in a conundrum. If you stop for a pedestrian but they don’t cross, how long do you wait? 5 seconds? 10 seconds? A minute? Can you really have any rule there that would allow you to break the letter of the law and cross a crosswalk with a waiting pedestrian? And how often will an autonomous vehicle come to a complete stop because a person is near a crosswalk, even if they aren’t crossing? Will there have to be a manual override? However will that work?

Yet everyone driving a conventional car was able to quickly and easily tell that this woman was not crossing the street. Every so often she would wave her arm. An autonomous vehicle would have little ability to discern this movement. Waving at a friend? Waving at a person? Waving cars ahead? Waving because she was just released from an underfunded mental institution and waves at everyone? It turns out, the waves were pretty well correlated with the passage of taxicabs. Aha, she was hailing a taxi! This is something that every driver was able to intuit immediately, and no one stopped for her at the crosswalk. But an autonomous vehicle would be stuck. For how long? Who knows. Imagine a cab traversing 5th Avenue in Midtown Manhattan? It would wind up screeching to a halt every block as a New Yorker flung out a hand to try to nab an empty cab.

Sure, there might be fixes to this specific problem. Maybe Uber will render taxis a thing of the past. (But then won’t people waiting on the curb for an Uber create the same type of problem?) Maybe every taxi will be fitted with a transponder so that an autonomous car can see a person waving and correlate it to the location of a taxicab and make the connection that they’re hailing a cab. (Which seems to be a complex solution to a simple problem.) Maybe people will learn to hail cabs only away from crosswalks (fat chance). And even if this problem is somehow solved, there are thousands of others like it. Driving a car in a busy city has infinitely more scenarios than on a controlled access highway. You can control for one outcome, but there are thousands of others that may pop up.

And many of these will be one-off scenarios. The aforementioned intersection at Pearl Street is probably unlike most any other in the world. Cyclists are not required by law to use hand signals. A car may not signal, but may shade to the right, something some motorists (and many cyclists) know means they’re probably going to turn. To get around a double-parked car, you may have to cross the double-yellow line. Human drivers can pretty easily assess the scenario and risks involved and decide whether to operate outside the letter of the law. But an autonomous vehicle, in any of these situations, may find itself stuck. The whole selling point of the self-driving car is that it will be able to operate without a human driver. But in cities, it seems that there would have to be frequent manual overrides when the car finds itself between a rock and a hard place: where it can’t go forwards without breaking a rule.

People are good at breaking rules—and in city driving, bending the rules is frequently a necessity. Computers—by design—are not.

When Multiple Agencies Attack … a NYT Reporter

The New York Times ran an article this week wherein a reported attempted to navigate Los Angeles by transit. There’s an obvious faux pas in a picture caption (see right, and see if you can figure out what it might be), but otherwise the piece is a list of trials, tribulations and eventual successes trying to navigate Los Angeles by something other than a car.

Sometimes successfully.

As someone who once navigated LA for a week mostly by transit—aided by an iPhone and, at times, a friend at USC—I can empathize with Mr. Hanc to a degree: it can be hard to figure out how to use the system. And while I would criticize some of his convoluted routes and relying on infrequent direct buses when there were better options (and, yes, I’ll try to reconstruct his journeys later), another glaring issue is the multi-agency mishmash, especially in the part of LA where many of his travels took him: the area between Westwood, LAX and downtown.

First, Metro’s system is huge. The LACMTA carries more than a million passengers a day; only New York carries more. Since New York has the bus system separated out by borough, it’s probably the most complex system map in the US. Seriously, check it out:

Good luck making sense of that! But to add insult to injury, there are no fewer than 47 (forty-seven!) municipal bus operators. LA Metro has a long history of interagency squabbles—it was created in 1993 after two separate operators were merged because they almost built two subway lines that didn’t connect. And while, as far as I can tell as an outsider, there is not much contention right now, there are certainly still multiple agencies running multiple—and sometimes parallel—services, without fare or schedule integration.

It makes it tough, especially as an outsider, to use the system. When I was there, without time constraints, I stuck to Metro services (and a trip on Metrolink, the region-wide commuter rail service) even when another trip might have been better. I had a 7-day pass, and didn’t want to bother with learning the transfer purchase system. So I stayed away from Dash, and the Culver CityBus, and the Big Blue Bus, and others. But in the area that the Times author was traveling, he had too many choices, which led to enough confusion that he wound up taking at least one trip by car, and convoluted routings on others.

There’s obviously a lot of history and issues of local control, but from an outsider, it makes the whole system—which is complex enough already!—a pain to use. I know if, for instance, I’m in Chicago, and I want to go to a suburb, I might wind up on Metra and a Pace bus. Or that in New York I might need to take NJT or a Bee Line Bus or a bus out on Long Island. But to go from LA to Santa Monica is like going from Manhattan to Brooklyn, or the Near North to Wicker Park. Even in San Francisco, home to dozens of local agencies (many of them large—AC Transit is the tenth largest bus system in the country) the boundaries are generally clear: Muni in the city, AC across the bay, SamTrans south, Golden Gate north, VTA in San Jose.

In LA, all bets are off. It means that local riders may be penalized for crossing a city line; at least in San Francisco, the systems are county-run, and the dense cities (San Francisco and Oakland) only really have one system to use. Anyone unfamiliar with transit—whether a car-driving local or a visitor—will be flummoxed, as the author was:

But when I got to Westwood, I was dumbfounded. Buses of every size and color whizzed by: big blue City of Santa Monica buses, green Culver City buses, blue and white U.C.L.A. “Bruin Bus” shuttles. A barista at a nearby Starbucks pointed me to the one I wanted: the Metro Rapid 734 bus.

If you’re LA, and your reputation is already that it’s hard to navigate by transit, extra barriers to entry don’t help. The LACMTA is actually a pretty good system, buses are frequent, well-marked, go most everywhere, and once you learn the difference between an orange local bus and a red “Rapid” bus, as well as the fares (no transfers, cheap day passes) and a few other eccentricities, it’s easy (if not always speedy) to use. That is, unless you wind up going somewhere served by another agency. Then it’s almost as if you’ve flown to another city, even if you’re a mile away.

So, to recreate John Hanc’s journey, using GTFS, which has most transit agencies in it (and which I think he could have been helped by):

His first trip was from LAX to an unnamed hotel that overlooked the 405 he had to take the 734 on Westwood to get to. The 734 crosses the 405 on Sunset before going over the Sepulveda; it’s likely that it he was staying at one of the hotels at or near Sunset and Sepulveda. While he chose the airport bus to Westwood, a more frequent and less confusing option would have been the Culver CityBus 6 or 6R to Westwood ($1 fare instead of $10) from the airport bus transit center, and then a change to the 734. That bus would have dropped him on Westwood, not a few blocks away, for an easier transfer. Still, it’s multi-agency, so it’s not simple. And you have to get to the first bus on an airport shuttle, too.

The next morning he went from his hotel to the Hammer museum. He got a ride, even though it would be an easy, one-seat ride on the 734, every 20 minutes or so.

Next, he needs to take an afternoon trip from UCLA to downtown LA. This should be pretty easy, if not super fast. His buddy Mark works right downtown, near the terminus of all the buses and near the actual subway. Somehow Hanc finds a commuter bus that runs less frequently (four times a day!), and trades frequency for speed—and winds up waiting an hour for it. There’s a LA Metro route 534 from Culver City to Malibu, but it’s not the route he’s looking for: he wants a LA DOT 534, which is a different service entirely, although the fare media are at least integrated. Here, it pays to learn that any time you might make up waiting for an infrequent service you could spend already moving towards your destination, albeit slowly.

But it’s another illustration of how convoluted the overlapping systems are. You can take the LA DOT 534, or you can take Metro 720 to the Red/Purple Line, both of which will get you downtown in about 1:00, and which run parallel to each other. But there’s no fare or schedule integration. Maybe it makes sense for a daily commuter. Maybe. But for an outsider? Forget about it. It should be noted that if and when the Purple Line Extension a.k.a. Subway to the Sea (although it won’t quite get there) is completed, it will be a one-seat subway ride from Westwood to downtown, rendering the current alphabet soup for that ride moot. This might be done in 20 years.

Did he have to even go downtown? He could have taken an express bus due north and met Mark in Valley Glen, saving Mark the drive out of the way to pick him up, and himself the long wait for the bus. Since LA has no real center, it’s generally possible to get from one place to another without going downtown. (Although maybe he and Mark had dinner downtown; he doesn’t say.)

The next day he takes a BRT Line to a Subway. Easy. (Apparently Mark prefers to sit in traffic even though he lives walking distance from the Orange Line.) Then he was taking the Antelope Valley Line out to Newhall and coming back to Burbank, before transferring one stop outbound to the Burbank airport. He could have taken the 164 to Burbank, and then gone outbound on Metrolink from there. That would have also meant he would have bought a ticket from a machine rather than a person (and, yes, it’s perfectly fine to buy a ticket between non-downtown locations). And on the way back, rather than backtracking to Burbank and switching trains, he could have, again, taken a train to a bus.

So kudos to John Harc for sorta kinda getting around LA by transit. If only he’d actually planned ahead a little more, he could have saved a lot of time. And a couple of rides with Mark.

Bus Lanes on the Harvard Bridge

April was Bus Month here at Amateur Planner, and May is showing no signs of slowing down. I noticed recently that in a traffic jam on the Harvard Bridge (which occur regularly, especially during baseball season), there are not many buses on the bridge, but they carry a large portion of the people crossing it. So I waited for the next traffic jam on the bridge (not a long wait) and went to take a photograph, which I then annotated:

This was taken at the 250 Smoot marker (so about two thirds of the way to hell), and I noted that, in stopped traffic, there were 20 cars per 100 Smoots (this is a bit more than 25 feet per car; Smoot markers make it really easy to quickly measure things). I took a quick census of the number of people in each car (appeared to be about 1.3) and set about making the graphic above. (The bus numbers account for one at all-seated capacity, one at normal standing capacity, and one at crush load.)
Then I tweeted it, and it may have gotten retweeted a couple of times.
There was one bizarre (in my opinion—and I’m really not sure if it’s uninformed or malicious) response thread, which amounted to the following (as requested by the Tweeter, the full conversation is below):
This is where the bus does go. (1/4 and
1/2 mile buffers of MBTA bus routes.)
So, pretty much everywhere.

Responder: Plenty of people need to get where buses don’t go.
Me: I’m fine with them having one lane of the Harvard Bridge, and the buses go a *lot* of places; if they ran faster than cars, more people would take them.
Responder: So glad you’re not making the rules.
Me: Here are areas within 1/4 and 1/2 miles of bus routes, where again are people going that the buses don’t go? [See map at right.] And why should my tax $$ go to pay for buses to sit in traffic so cars can … sit in traffic? >50% of the people on the bridge are in buses. Why not give them 50% of the space?
Responder: It’s the when, not the where. Bus schedules don’t nec. match ppl’s schedules. RedSox fans all over NE. [editor’s note: see original Tweet in thread.]
Me: So if the buses were 15 minutes faster than driving, people would take them, and anyone who *drives* to Fenway deserves a dope slap. [There’s] plenty of parking at Alewife-Riverside-Wellington-Wonderland. Trains run every 5 mins. Why should 20k+ bus passengers be delayed 10 mins for a few Sox fans?
Responder: It’s about making connections too—when too many connections get inefficient, driving works.
Me: Driving works? Tell that to the people on that bridge: people were walking faster. Bus lanes means more people opt for transit, fewer cars overall, and less traffic.
Responder: Just because buses work for you doesn’t mean they work for all.
Me: That’s the problem. They don’t work. The deck is stacked in favor of driving. I’m not saying ban cars, I’m saying let’s equalize street real estate. Why shouldn’t a bus with 50 passengers have priority over a car with 1 or 2?

But this is the usual reactionary inability to see the greater good. Take away a lane from cars, and it’s an affront to driving. An affront to freedom. Un-American. Never mind the majority of people on that bridge aren’t driving cars. They don’t matter. Still, I haven’t heard this turned in to an equity argument, so that’s kind of groundbreaking.

So the first part of this blog post is a plea: Ms. Cahill, I want to know what goes through the mind of someone who can’t see that transit efficiency is a societal benefit, and that it will amount to more people using fewer vehicles. Please email me, comment here, and discuss. I want to know.

The second part is me, trying to quantify what would happen to vehicles displaced by a bus lane on the Harvard Bridge, and what the time savings would be for bus riders as opposed to the time penalties for drivers. And, as I am wont to do, I did this in chart form. I imagined a hypothetical traffic jam stretching across the bridge (0.4 miles) in a closed system where all of the cars feed off of Mass Ave on to the bridge (this is close to the case, but some traffic does enter from Memorial Drive):

At first glance, going from two lanes to one would double the length of roadway needed to store the same amount of cars. But several other factors come in to play. First of all, the buses take up the space of 8 cars—at least. Then, we can assume that 10% of the cars remaining will shift modes: if taking the bus is all of the sudden significantly faster than driving, people will use it. And people in taxis (by my estimation, 10% of the traffic on the bridge) will likely switch in greater numbers since they’re starting closer by: I estimated 50% mode switch there. Then there’s induced demand: make the traffic on Mass Ave worse, and some drivers—I said 10%—will choose another route, whether it’s the Longfellow or the BU Bridge or further afield.

Add these together, and I would guess that traffic would increase by between 1/3 and 1/2. Assuming that traffic moves at 5 mph, this would mean an increase of 2.5 to 4 minutes for each person in a car on the bridge. But it would also mean that buses would cross unencumbered by traffic, making the trip in one minute, and saving every bus passenger 7 (this assumes that the bus lanes extend back to Vassar Street, displacing bus stops and a few parking spaces on Mass Ave through MIT). With these numbers, drivers would incur 510 minutes of additional delay, but bus passengers would save nearly three times that much time—a dramatic benefit.

Am I way off base with these numbers? I don’t think so. When the Longfellow went from two lanes to one, vehicle traffic decreased by nearly half! Traffic spread to other locations, people chose other modes (walking, biking, transit), or didn’t make trips. The traffic apocalypse that was predicted didn’t materialize, and life has gone on.

The Harvard Bridge is one of the most heavily-traveled bus corridors in the city, up there with the North Washington Bridge, the Silver Line on Washington Street, the 39/66 concurrency on South Huntington, portions of Blue Hill Avenue, some streets to Dudley and the feeder buses to Forest Hills. (All of these should have bus lanes, by the way.) The 1 and CT1 combine for more than 15,000 trips per day and, at rush hour, better than one bus every 6 minutes. The bridge also carries the heavily-traveled M2 MASCO shuttle 6 times per hour. Combined, these routes account for a full (usually crush-load) bus every three minutes—which is why in a 10 or 12 minute traffic jam there are three or four buses on the bridge at any given time—transporting at least 1000 passengers per hour.

Bus lanes would allow these bus lines to operate more reliably, more efficiently and more quickly, meaning the same number of buses could run more trips, and carry more people. Which, if they’re 10 minutes faster than cars, they’re going to be carrying! This would be something that could be tested and quantified, and it could be done as a temporary pilot with cones and paint. There is no parking to worry about, no bus stops to relocate: just set aside one lane for buses (and give buses signal priority at either end of the bridge). This would take the cooperation of MassDOT, DCR, Boston and Cambridge—and prioritize “those people” riding transit over real, taxpaying non-socialist Americans—so I don’t expect it to happen any time soon.

Going in circles on the Silver Line. Or, how the T could save $1m tomorrow.

In my last post on the Silver Line, I wrote about how the poorly-timed light at D Street causes unnecessary delays. If you’re lucky enough to get across D Street, you then go through the power change at Silver Line Way and then begin the loop back to get on to the Ted Williams Tunnel to the airport (and soon, Chelsea). The end of Silver Line way sits right above the tunnel portal. But to get to that point requires a roundabout route, often in heavy traffic, which takes a full mile to return you right to where you started.

If only there were a better way.

There is.

After leaving the busway, the Silver Line outbound route goes down the Haul Road, merges in to a ramp from the Convention Center and D Street, and runs fully half the distance back to South Station—in mixed traffic—before finally turning on to the Turnpike towards the tunnel and the airport. What’s the point of building a bus rapid transit corridor if you then spend the same distance sitting in traffic to get back to where you started?

What’s worse, the “Bus Rapid Transit” endures two traffic lights in mixed traffic, and this traffic is often heavy, especially when when convention traffic from the nearby convention center spills on to the highway at already heavily traveled times of day. The route is more than a mile long, and in perfect conditions takes 3 or 4 minutes, but in heavy traffic can easily take 10 or 15; this traffic especially renders the “rapid” part of BRT useless.

Before entering this morass, there is access to the tunnel via a ramp next to a state police facility. If the buses could use this ramp, they would save three quarters of a mile of travel, two traffic lights, a yield at a merge and, conservatively, two minutes per trip. Combined with the potential savings at the D Street light, these two improvements could save 10% of the total round trip time between South Station and Logan—or Chelsea.

Now, perhaps there’s a technical reason the Silver Line buses couldn’t use the ramp. Maybe it was too steep for the buses. But in 2006, when part of the tunnel collapsed, the T was granted permission to use the “emergency” ramp to access the tunnel beyond the panel collapse. A Globe editorial from that summer praised the T for its quick thinking in utilizing this routing. Yet when the tunnel panels were fixed, the buses were rerouted to the roundabout course which brings them halfway back to South Station before they enter the tunnel.

MassDOT actually has these buttons.
Time to put them in to action.

There’s obviously no physical reason this ramp can’t be used, since it was used in the past. And any argument that the merge wouldn’t be long enough to be safe is unconvincing, especially since it would only be used by a bus every four or five minutes, even when the Gateway project to Chelsea is completed. The in-tunnel merge has 1/10 of a mile before the lane ends, far longer than similar merges on to the Turnpike in the Prudential Tunnel. Suggestions that this would be unsafe are protective hokum; with appropriate merge signage (perhaps even a “bus merging when flashing” light) there should be no reason why this can’t take place safely. The Transportation Department, MBTA and State Police need to convene to figure out the best way to use this facility, but the answer certainly should not be the usual “no,” or “but we’ve always done it that way.”

There’s an environmental justice piece, too, especially with the extension to Chelsea, a disadvantaged city a stone’s throw from Downtown Boston, but a slow ride away by transit. Right now, Chelsea residents are at the whim of the 111 bus—and the traffic on the Tobin Bridge. It seems foolish to build a brand new bus line to Chelsea but not to address one of the major bottlenecks on the rest of the route. If the Governor is serious about implementing reforms to improve service and save money, he should look beyond specious claims of sick time abuse and at where interagency cooperation could save time for passengers and time and money for transit operations.

Dr. Evil. Transit economist.

It costs the T $162 to operate a bus for an hour. The SL1 Airport service operates 128 trips per day, and we can reasonably expect that the Chelsea service will operate with a similar frequency. Fixing the D Street light and using this ramp could conservatively save 4 minutes for each of these 256 trips, which would equate to an operational savings of $1,000,000 per year.

Is this a drop in the bucket as far as the T’s overall revenue is concerned? Sure, it’s less than one tenth of one percent. However, it’s a million dollars that could be saved, pretty much overnight, with basically no overhead investment. We spent more than half a billion dollars building the Silver Line tunnel and stations, and acquiring the buses. And the SL1 buses actually turn a (slight) operational profit! It’s high time we removed some of the stumbling blocks it’s saddled with and let it operate with a modicum of efficiency.

#FixTheSilverLine

Where could the MBTA implement unscheduled short turns?

I recently wrote about short turning a bus on the EZRide Shuttle route. People will ask: “why doesn’t the T do this, my bus is always bunched?!” The answer is a) it’s not easy to do, b) they are way too understaffed to do so, and c) their schedules are so much more complex that there are many more moving parts. At rush hours, the T has four dispatchers watching 100 buses; my office has one or two watching nine (although it’s not our only job, sometimes it demands full attention). The need for short turns arises at times when there is heavy traffic and ridership. At those times, it’s all the dispatchers can do at that time to keep some semblance of order among the 250 buses they’re watching, not turn their attention to one particular part of one single route.

And also: there are only so many places and times you can successfully execute a short turn. Our route has a lot of twists and turns which make it easy for a bus to take a right instead of a left and go from outbound to inbound, but often a short turn may require a bus to go around a narrow block in traffic, and you certainly don’t want a bus getting stuck on a narrow corner where it doesn’t belong. There are more issues with the T: we know our drivers are on one route and that their shifts end around the same time. I’ve actually had times where a driver couldn’t cover an extra run because he or she had to be at another job; this is more frequent at the T where shifts start and end in a very complex scheme and at all hours of the day; a driver might finish one trip and set out on a different route, so a short turn would find them far away from where they needed to be. And finally, the T has thousands of drivers, so there is no way for a dispatcher to know whether a driver is familiar with the route and where to make a turn, or whether it’s his first day in the district and he or she is following the route for the first time.

Trains? Buses are much easier than trains. Trains require operators to change ends, change tracks—often at unpowered switches—and obtain a ton of clearance to do so, especially on the older sections of the MBTA system which don’t have the kind of new bi-directional signaling systems that, say, the DC Metro has. If the T had pocket tracks in the right places, it might be easier. But without them short turns would only save time in a few circumstances and a few areas.

And on a train you’re dealing with even more passengers. I’ve been on trains expressed from Newton Highlands to Riverside. Even with half a dozen announcements, a couple of stray passengers won’t pay attention (buried in their phone, perhaps) and then wonder why the train is speeding past Waban. I’ve heard of crews at Brigham Circle, after switch the train from one side to the other, walking through the car rousing passengers who are on another planet (or just staring at their phones). If you can’t run a short turn expediently, it’s not worth doing at all.

That being said, I have a couple of thoughts on routes which could benefit from more active management and, perhaps, some short turns. Both are frequent “key” routes, both experience frequent bunching, and both carry their heaviest loads in the middle of the routes, so that the passengers from a mostly empty bus in the trailing half of a pair could be transferred forwards without overcrowding the first bus. The are (drumroll please): the 1 and the 39. Let’s take a quick look:

Actual NextBus screen shot for the 1 bus.

1. The 1 Bus is one of the busiest routes in the system (combined with the CT1, the Mass Ave corridor has more riders than any other such route except the Washington Street Silver Line) and frequent headways of 8 minutes at rush hours. There is no peak direction for the route; it can be full at pretty much any time in any direction. And it is hopelessly impacted by crowding and traffic, such that bunching is almost normal, and on a bad day, three or even four 1 buses can come by in a row, with a subsequent service gap. (It could benefit, you know, from bus lanes and off-board fare collection, but those are beyond the purview of this post.)

But the 1 has a couple of features that make it a candidate for short turning. First of all, its highest ridership is in the middle of the route. The route runs from Dudley to Harvard, but the busiest section is between Boston Medical Center and Central Square. Going outbound (towards Harvard) many passengers get off at Central to transfer to the Red Line or other buses, inbound (towards Dudley), many passengers get off at Huntington Avenue and the Orange Line to make transfers. So here’s a relatively frequent scenario:

The black lines show the actual headways. The red
shows what could be accomplished by short-turning
one of the bunched buses at Central Square.

An outbound 1 bus gets slightly off headway, encounters heavy crowds, is filled up, and runs a few minutes behind schedule. Meanwhile, the bus behind encounters fewer passengers, spends less dwell time at stops, and catches the first bus. The first bus may have 60 passengers on board and the second 30. The buses remain full past MIT and pull in together to the stop at Central Square, where two thirds of the passengers disembark (and few get on: it’s faster to the the Red Line to Harvard or beyond). So now, the first bus has 20 passengers on board, and the second 10. In the mean time, since the first bus is behind schedule, there is now a 20 minute service gap: the first bus should have looped through Harvard by now, and if the buses proceed as a pair, the first bus will pull right through the loop and head out late and with a heavy load, and even if the second bus has a few minutes of recovery, it will quickly catch the first, and the process will repeat inbound.

You won’t be shocked by this, but I went to Nextbus, pulled up the map for the 1 bus, and at 10:15 p.m. on a weeknight, found this exact scenario. See the map to the right. The first bus has gotten bogged down with heavy loads, so there is a 22 minute gap in front of it, while there is another bus right behind. The bus in front should be going inbound at Central right now, but instead both will continue to Harvard, loop around, and start the route bunched: the second bus will lay over for about three minutes and, most likely, after passing several vacant stops, be right on the tail of the first.

This is what the 1 bus route should look like
without any bunching. This is somewhat rare.

And the loop is a particular problem since there is not time or space there for the route to have recovery time, so if a pair of buses enters bunched, they are likely to leave bunched as well. Instead of having proper recovery time at each end, only Dudley serves to even out headways. So bunches are much more likely on the inbound (Harvard-Dudley) having occurred going outbound. And given the traffic, passenger volume and number of lights on this route, bus bunching is likely.

But what if, magically, that bus could be going inbound? Well, it could, and it wouldn’t be magic. It would be a short turn. If a dispatcher were paying special attention to the route, the operators could consolidate all passengers on to one bus in Central Square. At this point, the empty bus could loop around and resume the trip inbound from Central (even waiting in the layover area for a minute or two if need be to maintain even headways), where the bulk of the passengers will be waiting. The bus with passengers will continue to Harvard. On the subsequent trip, every passenger’s experience will be improved. Anyone waiting for a bus inbound from Central will have service 10 minutes earlier—on a proper headway. And passengers between Harvard and Central will have a bus show up when it would have, except instead of quickly filling up as it reaches stops which have had no service for 22 minutes and subsequently slowing down, it will operate as scheduled.

Note that one bus is catching the other. This is the start
of the bunch. 10:09 PM. It’s not too late to short turn!

I watched the route for a while longer, and as predicted, the pair of buses looped through Harvard together, and then traversed the entire inbound route back-to-back, meaning that everyone there waited ten extra minutes, only to have two buses show up together. Every inbound passenger experienced the wonders of a 22 minute headway when the route is scheduled for 12. However, with one dispatch call and a transfer of a few passengers in Central, the headways could have been normalized, and the route could have been kept in order. An issue which was apparent at 10:09 (see the screen capture to the right) could have been fixed at 10:15; instead it lasted until nearly 11:00 (see below):

Now, is this easy? Hell, no, it’s not easy. First of all, the drivers have to know that it might happen. Then, they have to be able to clearly communicate it to the passengers. (If you focused on a couple of routes, you could have Frank Ogelsby, Jr. record some nice announcements. Imagine that deep baritone saying “In order to maintain even schedules, this bus is being taken out of service. Please exit here and board the next bus directly behind.” Oh, and of course, “we apologize for any inconvenience this may have caused.”) You’d have to be damn sure that there was another bus behind and its driver was instructed to pick up the waiting passengers. And a thank you Tweet (@MBTA: Thank you to the passengers of the 1 bus who switched buses so we could fill a service gap at Central) would be in order.

Would it be perfect? No. Sometimes you’d have an issue with a passenger who didn’t want to get kicked off the bus. If a bus had a disabled passenger on board, the driver could veto the short turn based on that fact, since the time and effort to raise and lower the lifts would eat in to the time saved by the turn. But most of the time, if executed well, the short turn would save time, money, and create better service for most every rider.


39. The 39 bus is similar. It is heavily used, and it bunches frequently. It also has its heaviest loads in the middle: the stretch between Back Bay Station and Copley is mostly a deadhead move, the bus only really fills up in the Longwood area, and the bus is mostly of empty of passengers along South Street from the Monument in JP to Forest Hills. So at either of these locations, a similar procedure could take place. If two buses were bunched going inbound, the first could drop off in Copley, take a right on to Clarendon, a right on to Saint James and begin the outbound route, rather than looping in to Back Bay and then out again to backtrack to Berkeley before beginning the route. Back Bay is necessary as a layover location when buses are on schedule, but there’s no reason to have a bus go through a convoluted loop when it could be short turned and fill a gap in service.

At the other end, two bunched buses could consolidate passengers on Centre Street in Jamaica Plain, at which point one could loop around the Monument (already the layover point for the 41) and begin a trip inbound, while the other would serve the rest of the route to Forest Hills.

So those are my two bus routes that could be short-turned and unbunched. Combined, they carry 28,000 passengers per day: the busiest routes in the system. I would propose a pilot study where the T figured out when these routes are most frequently bunched (they have these data) and then assign a dispatcher to watch only these two routes during these times and, when necessary, short-turn a bus to maintain headways, along with some driver training to ensure proper customer service and expedient routing. It could also record messages, put up some signs, and make sure to have some positive outreach to passengers. This could be done for a period of time, and the results analyzed to see the effect of actively dispatching such routes. If it were deemed a success—if there were fewer bunches and service gaps (data could show this)—the program could be expanded, and perhaps automated: any time buses were detected as being bunched, a dispatcher could be notified, and then make a decision on whether it would be appropriate to short-turn the bus, or not.

The passengers—well, we’d certainly appreciate it, too.

The art and science of a short turn

This post has been a long time coming. A while back I asked people on Twitter if they would be interested in a post about bus bunching and short turns (answer: a resounding yes) and have been stewing on it for a while. I’ve gotten some feedback that this post is too long, so if you don’t care (and it’s quite possible that you don’t) feel free to skip and read something else. Thanks to my coworkers for looking this over and giving feedback, and the bus drivers on the service who executed the short turn.


A bit of background: in my day job, I work for the Charles River TMA. One of the programs we manage is the EZRide shuttle: a small, last-mile commuter shuttle between North Station (major transit node) and Kendall Square (major employment center). The service has been around since 2002, is mostly funded by local employers and property managers, and sort of serves as another branch of the CT buses, connecting North Station, Lechmere and Kendall. We carry about 2500 passengers per day, and are near or at capacity at peak hours (7:45 to 9:00 AM, 4:15 to 5:30 PM). Most of our ridership is comprised of Commuter Rail riders who work in Kendall. The shuttle is free to corporate members and open for a cash fare to the public.


For the purpose of this blog, I am italicizing certain transity jargon and defining them at the end of the article. Our organization contracts the route to a private operator, and we both have dispatch duties. As it breaks down, they mainly deal with driver issues (broken down buses, drivers needing time off the bus, work schedules) and we keep an eye on passenger issues (loading, bunching, headways).


Our route sometimes allows us short turns, especially when there’s bad traffic, but that successfully implementing a short turn takes a lot of know-how, and a bit of magic and luck. Some short turns are relatively easy: two buses are running back-to-back, the first bus as 33 passengers and the second bus has two. (This sort of bus bunching—here’s the best resource on that from WBEZ—is all too frequent on busy routes, even when buses run at a scheduled, even headway.) If we can empty the second bus on to the first, we can turn the first bus back to fill a gap elsewhere on the route. This only works if there is a need precipitated by traffic, but that is often the case.


Since many people have asked (okay, maybe a couple people) for a description of a short turn, here is one, with way too many words, and a bunch of maps, too. A follow-on post talks about locations where the MBTA could implement short-turns.


*****


The Route


A short turn doesn’t just happen. It comes about from a unique set of circumstances, deep knowledge of the route, traffic, passenger loads, the weather, an innate, built-up sense of what the route looks like and how it will be affected by traffic and loading in to the future. Sure, there’s some luck thrown in, but most of that is self-made: a well-executed short turn should be more science than art—it just feels like luck when it works. (And it doesn’t always work; rule number one, before you even consider a short turn, is to try to at least not make things worse.) I’ll describe a recent short turn success, and the elements that go in to it. The whole of the operation, from diagnosis of the problem to the successful implementation of the turn, took about 12 minutes—likely shorter than it will take you to read this blog post.


We have separate morning and evening routes, due to passenger loading (our reverse-peak carries MIT students) and one-way streets. The route map can be found here, and our route in Nextbus’s interface here. The route requires several routes and jogs, mostly due to one-way streets, and it’s prone to traffic, especially during construction. Our evening route can be roughly divided in to four segments, each of which takes about 15 minutes, with 16 minutes of recovery time as follows:

Inbound:
Cambridgeport to Kendall Square (moderate commuter ridership, minimal traffic delays)
Kendall Square to North Station (heavy commuter ridership, moderate to heavy traffic delays)
[12 minutes of schedule recovery time (necessary due to traffic)]
Outbound:
North Station to Kendall Square (minimal commuter ridership, moderate traffic delays, although heavy recently)
Kendall Square to Cambridge (moderate student ridership, minimal to moderate traffic delays)
[4 minutes of schedule recovery time at Cambridgeport]

*****


The Situation



On Thursday, April 9, we had some operational issues. Due to traffic signal timing problems, O’Brien highway backed up, and we experienced a 10 to 12 minute delay on our outbound route (this section carries very few passengers at this time of day, but it is necessary to get our buses from the terminal back to the start of the route). On a nice day, we might have some buses operating empty outbound through Kendall Square, but with cold rain on April 9, we had no buses which were empty and could be rerouted, so we couldn’t deadhead a bus to the terminal, or an intermediate part of the route.


The scenario was to the point where we had a 15 minute service gap. This is not good for a few reasons. First, this is double our scheduled headway is 8 minutes, so this was nearly double our schedule, even if it means that waits will only be a few minutes longer. But the issues would cascade: the first bus to pick up during this gap would fill up well before the end of the route, meaning the headway for later stops would be longer and would wind up being based on the headway of the second bus, so it would wind up being more in the 18 to 20 minute range.

And then: the bus that was supposed to run called in with a mechanical failure. All of the sudden, 7 of our 9 buses were on the outbound route, and we were facing a 20-24 minute service gap. In other words, we were screwed. Here’s the setup:

The arrows show the inbound route, and the red dots show the major passenger generators at this time of day (peak rush hour); as you can see that there are no inbound buses between the west end of the route and the eastern terminal (just off of the map) except for bus 9901, which is most of the way there. (Ignore the times “late”; we’d already had some delays to this point.) Bus 711, shown in gray, is broken down. And the driver of bus 708, at this point, got off his bus to try to diagnose the issue of 708, and due to radio traffic we were unable to tell him to get on his [goddamn] bus and drive the [goddamn] route.

So now we had a problem. 706 caught 708. We needed a bus to run the route, but expected it to fill up before it could board all the waiting passengers, especially at the three red dots. It also coincided with the peak loading time for our route, when even under normal operations buses can load to capacity and leave riders behind. We could send a double draft to run the route, but then the second bus would wind up empty behind the first bus as it boarded passengers (most of our route is too narrow to safely pass) meaning that the passengers later in the route would have a longer wait. While I was yelling at no one in particular about 708 (in our office, using curse words) my boss (who has been watching this route for more than a decade: that’s institutional memory) mentioned that we could deadhead 706. What a splendid idea—as my ire grew with 708 for attempting to fix a broken down bus and not just covering the route I hadn’t noticed this possibility. (To be fair, the driver of bus 708 probably didn’t realize the situation on the rest of the route.)


*****


The Operation, or, the Rules of the Short Turn

Rule #1 of the short turn: Don’t Make Things Worse


The first question to ask in a short turn is: will this actually make much of a difference, and might it make things worse? If you are going to move heaven and earth to get a bus somewhere 90 seconds earlier, it’s much easier to just have buses run the regular route. Unless you can solve a loading issue and a headway issue together, it’s rarely worth doing. (A service gap in a non-peak direction affects many fewer passengers than in the peak.) The second question is: will this short turn now cause more problems later? If the answer is yes (and quite often it is), you have to weigh how severe of a problem it will be, and when it will occur. Can you solve an inbound issue at 5:15 that creates an outbound service gap at 6:15? Fine, better to improve the ride for 50 riders and inconvenience a handful at a much less busy time. If you can get two people off of the second of a bunched pair and on to the first, turn the empty bus and cut the wait time for two dozen, totally worth it. But if you’re trading off a delay for three people now versus a delay for five people later, it’s not worth doing. 


In this scenario, we were not going to inconvenience anyone, really, and improve service for a lot of people (and get buses better spaced in to the future). It was a no-brainer.



Rule #2 of the short turn: Know Your Route.

If you’re running a short turn, you need to know your route. You need to know where a driver can go around a block easily, or where they might get stuck in traffic (or worse: a tight corner not suited to a 40 foot bus, a frequent problem in Boston). Before you can do this kind of active dispatching, you have to know where you can safely and expediently turn a vehicle. It helps to have twenty-plus years of dispatching in the other two members of my office (I’m the new guy): they’ve been through everything. Construction detours, full road closures (the Craigie Bridge reconstruction), never-ending blizzards (okay, that was this year) and the like.


Due to the one-way nature of Kendall Square, the route does have a bizarre loop built in, which takes a couple of minutes to traverse but accesses a major stop. So one idea would be to deadhead bus 706 and have him run out of service (and preferably off-route down Main Street to Ames: nothing makes passengers angrier than seeing an empty bus drive by without stopping) and pick up at the last red dot on Broadway. If he got there expediently, he’d be able to at least pick up at that stop—and ensuing stops—and mitigate the service gap there, and take on the passenger load the first bus, 708, would not be able to pick up.


Rule #3 of the short turn: Be Invisible.


To passengers, at least. The best short turn is one where the deadheaded bus doesn’t pass any passengers waiting, where no passengers are asked to leave the vehicle, and where, except for the driver and the dispatcher, no one knows. This could also be phrased as “don’t piss off the riders” which is always a good policy: sending an empty bus past waiting passengers is a recipe for angry calls and emails. Generally, we operate under a policy of transparency with riders (we will suggest alternate transit means during especially bad traffic, for instance—it’s beyond our control but our goal is for our passengers to get where they’re going, not to boost our ridership), but we don’t feel the need to describe every piece of our operation. In the case of a short turn, we might send out a Tweet such as “Service gap inbound due to residual traffic delays and disabled bus. We will attempt to redirect service to fill this gap” usually suffice.



Rule #4: Know your Drivers

Now at this point it is worth pointing out that that you really need to know your drivers when juggling buses in this manner. Some of the drivers on our route could dispatch themselves: they have an innate idea of where every other driver is on the route, what their scheduled times are, and what their likely traffic and passenger load impacts will be. (Another recent night, two long-serving drivers basically rerouted each other and other buses, on the fly, to avoid traffic and fill route gaps far better than I could have even while staring a map of the bus GPS locations.) Other drivers are newer to the route and may not know the vagaries of Cambridge’s off-route street grid, and need a lot more guidance across the route. In this case, the driver of 708 is somewhat newer and knows the route fine, but harder to manage: we were happy that his only instructions were to run the regular route. The driver of 706 is one of our best and has been driving the route for a while; a simple instruction like “deadhead to Main Street, left on Ames, first pickup on Broadway” would be all that he’d need.

So that’s what we did. Bus 708 would run the regular route making all stops, and would likely be full at Kendall Square. (The buses we currently run are 35 foot buses with 32 seats and a stated crush load of 45, although more passengers have been known to cram aboard.) There was no point holding 706—we had another outbound bus behind him—so we sent him to do the pick-ups beyond Kendall, but to take a direct route there, leapfrogging ahead of 708 and shortening the wait at the subsequent stops (and we expected him to fill up at those stops). 708 would then run by those stops a couple minutes after 706, so would have fewer passengers to pick up. 


Rule #5: Pay Attention.


But the operation isn’t over until the buses are back on the regular route, drivers know future departure times, and they have recovery built in to get back to normal. So far, everything was going according to plan, but you have to pay attention to a short turn until it’s on its way to a logical conclusion. 706 had made good time on Brookline Street and had chosen an appropriate, off-route path for his deadhead; again, had this bus passed a group of long-waiting passengers, they’d go from irked to irate. 708 was serving some moderate-ridership stops, and headed towards Technology Square, where he’d take on many more passengers. 

#Protip: if two buses are coming together, take the second one. It’s unlikely to be any slower (it might actually pass the first bus) and you’re more likely to get a seat.

Anyway, the plan was working, rather swimmingly. And then: nirvana. See how, above, bus 707 is catching up to bus 709? While this is not a busy part of our route, but on a rainy day, there are some passengers who will take a circuitous bus ride to Kendall rather than make the walk. So while bus 709 was stopping for a rider here an there, 707 wasn’t, and he radioed in that he was behind bus 707, and was empty. Bingo. We were worried 708, upon reaching Kendall Square, would be too full for the boardings there. But 707 could conceivably balance the load between three buses as long he was slotted in before 708 reached Kendall. Each of the main passenger nodes would get its own bus, balancing the load well. If it worked. It was worth a try.



But remember: you have to know your drivers. 712 is a driver who had recently bid on to our route, and had had some issues with the route (not entirely his fault: our route flips based on the time of day—since we serve students and commuters in separate directions—and can be confusing for both riders and drivers to learn, although once familiar, it works quite well) and certainly didn’t know his way around Cambridge. In other words, if he’d been in 706 a few minutes earlier, it’s doubtful we would have sent him on the deadhead in the same way we did 706.

Somehow this worked.
But we could coach him through it. 706 and 708 had their charges, and the radio channel was clear. So the call went out. “707: take a left on Broadway, then proceed straight down Main to Third Street. Make a right turn there, and make your first pick-up at Kendall Square.” We’d have to watch him like a hawk and keep in radio contact: if he missed the turn there, at best we’d have to coach him on to Memorial Drive, and on to the outbound route (a portion of our route uses Memorial Drive, and our drivers have never missed the turn and gotten stuck under the Mass Ave overpass). At worst, we’d lose him across the Longfellow for half an hour. (Don’t laugh. This has happened.) The short turn can be dangerous.

And it worked! 707 made the short turn in to Kendall and instead of following 709 on the outbound switched to the inbound. Astonishingly, we had evenly spaced the buses with about 3 minutes between each, which is particularly impressive since that meant that 706 was now 6 minutes—nearly a full headway‚ ahead of 708, who had left the route terminal behind him! And both 706 and 708 were nearly full, so bringing in 707 kept bus 708 from reaching Kendall, filling up there, and then reaching the next stops later, with more passengers to pick up, filling further, and perhaps leaving passengers behind. Much of the credit goes to the drivers, who let us know their situations (when they were empty and bunched) and were willing to jigger their routes in order to balance the load. The fact that such reroutings are not infrequent means that they’re used to being asked to do so, and that they execute the maneuver well.

Once the buses had all made their way on route, we actually had well-spaced buses. In fact, 706 and 708 were a full headway apart at this point: had we not deadheaded and short-turned they’d both be where 708 was, and we’d have cascading issues as they both ran into and then out of the terminal late. (Often, a headway issue at 6 PM can be caused by a traffic jam at 3:30.) But the pieces of the puzzle had fallen in to place, and the short turn had been executed, successfully. 

This is pretty much what our map should look like in normal service. (Well, except that the buses were way off their originally scheduled runs, but if I look at the map and every bus is 20 minutes late, that means that we have even headways and just had some issue earlier on.)


As my boss said, it was ballet. It was all over in about 12 minutes. But the best part? We had the buses in numerical order: 706, 707 and 708. Boom.


*****


The Aftermath

Why “art and science (but mostly art)”? It’s often suggested that computers could do this better than people, and why do transit agencies employ dispatchers, anyway, since an algorithm would do a better job? But that assumption is flawed for several reasons. First of all, unless an algorithm has nearly perfect ridership data, someone familiar with the route will have a better idea of where and when stops have heavy demand. Second, an algorithm would have to be able to not only know that a deadhead route will have less traffic at a given time than the normal route, but also communicate that route to the driver (and, frankly, I don’t find Waze and its ilk that useful at the block scale). And the algorithm would have to know which buses were full and empty: passenger counters are not perfect, but a driver can pretty quickly and easily respond to a radio call of “do you have any passengers?”

But the fundamental issue is that this type of service is dealing with people, both drivers and passengers. It’s pretty easy for a person—with some knowledge of the route—to balance out which stops to serve, and in what order, and what stops to prioritize. Maybe you’re a bit less concerned with Kendall Square because it has a shelter, so a minute or two longer there isn’t a problem. Maybe you know that given the weather one stop is more likely to be used than another because it has an overhand or an alcove for people to stand at. Maybe you know one driver is able to navigate the route faster than another (we have one of these: he drives safely and smoothly, but knows the route so well he regularly covers it faster than any other driver), while another is slower. Maybe one bus is balky and you don’t want to push it lest it break down.


Certainly you don’t want to deadhead an empty bus past a full bus shelter, or incur the wrath of customers who—even if you are doing it for the benefit of the service—would be understandably upset. And it’s also important to know your drivers, know what they are capable of, and talk them through what they need to do. Because despite all the talk of autonomous vehicles and hyperloops, right now and for quite some time to come, buses are driven by people and carry people, and despite various limitations, there are certain things where the Turing Test is still yet to be achieved.


A subsequent post will discuss routes where the MBTA could potentially use short turns to mitigate the effects of bunched buses.

Glossary:

Deadhead: run an empty bus without stops, and possibly on a more direct route.
Headway: the time between buses.
Double draft: two vehicles running together; more of a train term coopted here.