Happy 115th birthday to the Green Line "B" branch, and thoughts on the future

Commonwealth Ave when it was provisionally named 'Massachusetts Ave' in 1885 (source)

The section of Commonwealth Avenue between Packard's Corner and Chestnut Hill Avenue was largely built in the 1890s. Trolley service along this relatively new stretch of Comm Ave began May 26th, 1900. Prior to that, service to Lake Street typically ran via Beacon Street and Chestnut Hill Avenue.

Construction of Comm Ave near Lake Street (source)

Trolley service near Wallingford Road, in the early years (source)

A description of a journey that was published in 1904:

From the Newton line, by taking a Commonwealth Avenue car, another attractive ride is afforded for the return journey. The car turns off to the left and runs through a delightful combination of city and country until it reaches the Brighton junction, off to the left being the links of the Kenilworth Golf Club. At Pleasant Street, on the left, may be seen the links of the Allston Golf Club, and one of the most picturesque county clubhouses in the country is visible across a little pond. The car comes back into Beacon Street again after passing Cottage Farm station

Yes, it existed: the Allston Golf Club house (source)

Tudor Manor, 1930 (source)

The electric streetcar service would eventually attract the transit-oriented development of the avenue that we see today, with large, graceful apartment buildings of various styles from the early to mid-twentieth century. Sadly, the current zoning code (from 1990) has chosen for aesthetic reasons to retroactively ban these kind of apartment buildings, and so none of them could be built today without many variances. That's a strange policy to maintain in a city that is ostensibly trying to generate housing units that are attainable to people of middle-class means.

Comm Ave near Allston Street, present day

1958 view from near Washington Street, during road-widening construction (source)

Snow didn't stop them in 1938, near Warren Street (source)

I was fortunate enough to view a presentation on the history of Comm Ave last year but it was not until recently that the slides and pictures were made available on-line. For more of these pictures and history, please visit the website.

What we now call the Green Line "B" branch has gone through many changes over the years. Obviously when the MBTA was formed, the rebranding changed it from merely having a streetcar number into being integrated as part of the color-coded 'rapid transit' map (sadly, while not really improving service). The reservation has been shifted towards the center as part of road-widening efforts in the 1950s and the 1970s, resulting in the awkward intersection at Warren Street, where work ceased. The trolleys gave way to big 'light rail vehicles' that now carry approximately 30,000 passengers a day, averaging a snail-like 6-10 mph due to overcrowding and degrading infrastructure. The stations have not seen much in the way of upgrades, either, largely remaining as tiny asphalt strips with the occasional concrete barrier or plastic shelter added.

Chestnut Hill Avenue station platform (for thin people only)

Looking down the hill

At times, many stops were eliminated or consolidated, most recently about ten years ago, when Mt Hood Rd, Summit Ave, Greycliff Rd, and Fordham Rd were permanently retired to help improve spacing. We're looking forward to having another four closely-spaced stations be consolidated into two appropriately-spaced, fully accessible stations. The T has promised us signal priority for years, and claims to be experimenting with it. We're still waiting for the use of all doors on the surface to help speed up boarding and alighting, as well as full accessibility for everyone.

As the twentieth century progressed, Comm Ave was turned more and more into an asphalt wasteland: big sections carved out for angled parking, with a few sickly looking trees inhabiting the neglected median islands that were left. The Green Line and its riders were largely disregarded, probably considered relics of the past that would be replaced by mass car ownership and buses. But the Green Line is a survivor. Despite how poorly it has been treated by the city and the MBTA, the "B" remains the busiest branch of the Green Line, and the surroundings remain highly transit-oriented, with some of the lowest car ownership rates outside of Boston proper.

We have an opportunity to change the future. The city is brewing up a design for what they call Comm Ave Phases 3 and 4. That covers the section of Comm Ave from Packard's Corner up to Warren and Kelton Streets. This is part of the section that was constructed in the 1890s, and it's 200 feet wide, a lot of space. Despite that, daily vehicle volumes are very low, about 12,000 ADT, a figure which is low enough that it could easily be handled even on a street with merely a single lane in each direction. Clearly, this should be a street designed for people. The city has claimed that they are going to do something to make the avenue much more friendly for walking, biking, and riding the Green Line. They claim that they will do something about the fact that there are extremely long intervals between crosswalks (and then those are also inaccessible to the disabled), with a fence blocking off part of Allston/Brighton from another. They claim that they can restore the idea of a Comm Ave 'greenway', an echo of its original conception, a park that connects from the Charles River to the Chestnut Hill Reservoir. The 21st century version of Comm Ave could be a lot friendlier to the community. But only if we remember to show up and hold them to it.

"Self-checkout" for passengers boarding trains and buses

While walking to the supermarket today, I passed by a trolley boarding a line of riders, at a station platform. One person would step up to the top stair, pay the $2.10 fare, and go inside. Then the line would slowly move along, trudging through the wind and snow.

At the supermarket, I collected my food and items, went to the self-checkout aisle, rang up $33, and paid it. I took my receipt, my bags, and went home. All of this accomplished without any waiting on line, nor with any interaction by a store employee.

As I was walking out the door, I realized how bizarre the difference was: I could be trusted to ring up and pay for $33 of assorted items at the supermarket, but not a $2.10 trolley ticket nor a $1.60 bus ticket. And that's hardly unusual. Many retail businesses have moved to the self-checkout model. It's a natural way of cutting costs and speeding up service, especially in the modern era. Yet, the MBTA continues to waste money, and everyone's time, delaying trains at stations while riders slowly file through a single door.

The stakes are higher for the T than for a retail shop. Delays to a transit vehicle add up and propagate. The long line at the station platform translates to a train that's late. Bunching gets worse. Lines get longer. The average speed of the system drops below 7 mph. Riders get antsy. Half-hour trips stretch out into an hour. People can't get on or off the vehicle easily anymore, while the driver hoarsely shouts "move to the rear!"

Wouldn't it make much more sense to use all the doors for boarding and alighting? The rear doors on the trolleys are wider as well. The newer ones have floors that are level with the platform, making it much easier for people with disabilities. Reduce delays, improve quality of service, help people with disabilities. Win, win, win.

In fact, it's such a good idea, that in San Francisco, the local agency MUNI decided to transition to all-door boarding on all of their vehicles. In the past, I have commented on my experience with MUNI's all-door boarding system. MUNI has a lot in common with the MBTA: an extensive subway-surface trolley network that uses light-rail vehicles nowadays, and many connecting buses.

Recently, MUNI released a report on their experience allowing all-door boarding of buses and trolleys system-wide. It has been a great success. The MUNI report identified three key findings:

• Shorter Stops – Legalizing All-Door Boarding has encouraged boarding customers to distribute themselves more evenly between the front and rear doors, thereby reducing average dwell times. Pre- and post-implementation surveys at busy Muni stops found average reductions of 1.5 seconds (38%) per customer entry or exit. All-Door Boarding also has improved dwell time consistency and lowered variability, an important factor in helping reduce vehicle bunches and gaps and making service more reliable and predictable.
• Faster Trips – From FY 2010-2011 through FY 2013-2014, average bus system speeds (including stops) improved modestly from 8.41 to 8.56 mph (2%). All-Door Boarding has helped keep Muni moving during a period of rapid growth in San Francisco and increasing demand on the transportation system. All-Door Boarding is just one of many tools such as exclusive transit lanes, transit signal priority and parking management that together can help reduce travel time.
• Improved Fare Compliance – A series of four fare surveys between 2009 and 2014 indicate that fare compliance continues to improve. The fare evasion rate has decreased from 9.5% to 7.9% over five years and the estimated uncaptured revenue due to fare evasion has dropped from $19.2 million to $17.1 million.

I hear that, especially after this winter, the MBTA is looking for opportunities to do more with less. How about a method that is proven to improve reliability, reduce costs, and generate positive cash flow? What are they waiting for!?

And, why not do exclusive transit lanes, signal priority and parking management as well, while they're at it. It looks like they have a willing partner in the city of Boston.

Comm Ave Phase 2A public meeting: Tuesday March 24th

March 24th, 6 p.m.

565 Commonwealth Ave (Kenmore Classroom Building)

Room 101

The city is holding their long-awaited Comm Ave Phase 2A public meeting on Tuesday. This deals with the segment of Comm Ave between Packard's Corner and the BU Bridge (non-inclusive). One of the biggest topics of contention has been whether or not the bike lanes would finally be fixed on Comm Ave to match the Boston Bike Network plan for having a protected bike lane on Comm Ave.

The status quo

Good news seems to be that they will be presenting some kind of protected bike lane option at the meeting, so that represents a major step forward for the city. The precise details remain to be seen.

Another one of the major problems on the street is the lack of a crosswalk at Alcorn Street and Naples Road. On one side is a densely populated residential area, on the other side is the neighborhood supermarket. Most people simply wait and cross the street over the tracks when clear. But, the engineers believe that people should be walking over 1,000 feet out of their way, traversing 6 extra traffic lanes and waiting through extra cycles of the traffic light, simply to get across the street. While carrying heavy bags. This is a clear case of a disconnect between the planning department -- who only see this street on paper -- and the people who live here.

Even in the heavy snowfall, people would still rather cross here than go around the long way.

(source)

So, while there has been a great deal of progress made on the design, compared to where it was 3 years ago, there is still some more to go.

Finally, I would like to mention that although the MBTA has finally put out a plan for much-needed station consolidation, it is not clear that they will be ready to go before the city starts the reconstruction project. That will put us in the absurd situation of rebuilding the street around the 4 old stations. Then, presumably, the MBTA will come along and cut those out, and rebuild 2 properly accessible stations, but at that point they will simply leave the old station locations as dead space. That's a terrible waste, and a lot of extra pain too -- as the time period of construction would be lengthened. It seems to make a lot more sense to simply get both projects done simultaneously, so that the new street doesn't have to waste space, and so that the station construction can proceed in parallel with the street reconstruction, in a fully integrated fashion.

Taking a look at Green Line average speeds by hour of the day

Stairs can make boarding
be unnecessarily difficult
for some people.

With the real-time data available for the surface Green Line since mid-October, I thought I'd try some analysis with my gathered database. One thing we can look at is average speed of travel. Although the trains can ostensibly move at up to 25 mph in their dedicated lanes, or even faster off-street, they tend to spend a lot of time waiting at signaled intersections and station stops. In fact, the more passengers that are trying to use the system, the slower trains tend to go: overcrowding results in long dwell times as it becomes harder and harder for people to squeeze on and off the train. This effect is made worse whenever the MBTA forces everyone to use only the front door for boarding and alighting the train. The front door is small, and it has stairs, which makes the process take much longer as everyone has to slowly file in and out of the tiny opening.

The net result is that the Green Line can sometimes feel like it is traveling more slowly than if you walked. Well, perhaps that is hyperbole. However, it is possible to outrun a Green Line train on the "B" branch. A typical human runner, with some training, can sustain about 8-9 miles per hour. So we should expect to see average "B" branch speeds in a similar range.

The first thing we can do is consult the schedule by using a convenient mapping website to plot a trip from Boston College to Blandford Street at 8 o'clock in the morning. We find that the MBTA expects a "B" train to take about 27 minutes to cover the approximately 4 mile distance. That's about 8.9 miles per hour. Does that match up with the findings from the real-time data?

The following zoomable line chart is derived by calculating average speeds for the surface "B" branch during each hour of the day from 5 a.m. through 11 p.m., and breaking it down by week. So, for example, we can see that on the week of November 3rd, average speed at 8 a.m. was about 6.79 MPH and at 5 p.m. (hour 17) the average speed dropped to 6.61 MPH. That corresponds to an approximately 36 minute trip between Boston College and Blandford Street. Note that this chart does not distinguish one direction from another, so it is quite possible that the peak direction is much slower and the off-peak direction moves more quickly.


Plot of "B" branch average speed in MPH for the hours of the day from 5 am until 11 pm, looking at each week in November and December separately.

The weeks with the most rapid travel appear to be the final two weeks of December. This is not surprising. Much of the passenger load on the "B" branch comes from the universities, and those are on break during that time. Slightly surprising is the distant third-place finish for the week of Thanksgiving. Although the performance is better than the "normal" weeks, it is still rather low for a week when most students are traveling.

The "B" branch gets busy during the
off-peak hours as well.

In any case, the shape of the chart overall is telling. The two major valleys correspond to the traditional rush hours, when crowding on the Green Line grows extreme and dwell times increase accordingly. The most snappy performance is found either in the very early morning, or later in the evening. There seems to be a slight bump around 9 p.m. that might correspond to the late dinner and nightlife rush.

The difference between an average speed of 6.61 MPH and 10 MPH doesn't seem like much, but it is actually quite a bit: that's a difference of 12 minutes in end-to-end trip times. If the Green Line can manage an average speed of merely 10 MPH on a consistent basis, then a typical passenger can realize a savings of up to 12 minutes on their commute each way. That's pretty significant. Especially if you are able to increase reliability and cut out the variances that can sometimes lead to 15, 20 or more minute delays.

That's why I find prosaic improvements such as proper station spacing, transit signal priority, and all-door boarding to be vital. They don't have the same flashy pizzazz as building a new section of subway. But they can achieve much of the same benefit at a fraction of the cost.

At long last, the MBTA announces station consolidation design meeting for the Green Line "B" branch

Thursday Oct 23rd, 6pm, at BPL Copley: Commonwealth Salon.

Long time readers will recall that I have been writing about the need for station consolidation along the "B" branch of the Green Line for a few years now, in addition to articles on other topics related to Green Line operations.

It seems that the time has come for the MBTA to finally put forth a design for station consolidation within the scope of the upcoming Commonwealth Ave reconstruction project. These stations to be considered are the most closely bunched stations on the "B" branch, and clear candidates for consolidation:

The need for station consolidation on the "B" branch

Station consolidation has not been considered on the Green Line for over ten years now. The outcome of this design could result in what might possibly be the most significant service improvement in decades; a benefit for beleaguered "B" branch riders. Going from four, very closely-spaced, inaccessible stations to two, reasonably-spaced, accessible stations will greatly improve the riding experience of the vast majority of passengers.

When this concrete improvement is combined with electronic improvements such as signal priority, and organizational improvements such as all-door boarding (all the time), the result could be quite amazing. The MBTA still has some ways to go in reforming itself so that easy organizational and electronic improvements are possible to implement. But that can be done anytime. On the other hand, we won't see another chance to fix station spacing for a whole generation. This is the time to do it, and it is the time to do it right.

Vision for the Green Line moving forward: a focus on accessibility for everyone

The effort to improve Commonwealth Ave Phase 2A is well under way and there are many proposals to fix the sidewalks and the bicycle facilities that are under discussion. For this post, though, I want to discuss the MBTA Green Line, because of the reservation that runs along Comm Ave, as well as the ones that are on Beacon Street and Huntington Ave.

Generally, when other people speak of "vision" in relationship to the Green Line they probably are thinking about the Green Line Extension project at the other end in Cambridge, Somerville and Medford. That is certainly an exciting project and will make a huge difference to people living there. It's also making a big splash at $1.3 billion. However, in terms of big infrastructure, it's a decent move even at the inflated price, because it has the potential to attract many tens of thousands of riders. The main thing here is to ensure that the project is seen through to at least College Ave. Pushing for extensions to Route 16, and along the Fitchburg branch to Porter Square, are possible thoughts for the future.

The vision I have for the Green Line does not involve any further extensions, however, although it does not preclude them. After the bulk of the work on the GLX is complete, with the to-be-built Brickbottom Yard in place, the Green Line will be in a "balanced" form for the first time in modern history, with major maintenance and storage facilities both west and "east" of Park Street station. Plus, hopefully by that time, the MBTA will have concluded enough of its "power study" to comprehend what, if anything, needs to be done about the traction power system. And we'll be closer to having some new vehicles, beyond the 24 ordered for the first segment of the GLX. All this infrastructure should enable easing some long-standing Central Subway scheduling and congestion difficulties. But infrastructure is only part of the story.

Jarrett Walker made a good point in a recent post where he said that transit infrastructure does not cause ridership -- transit service causes ridership. And that is true: the frequency, reliability and speed of the transit service is what attracts (or repels) ridership. The Green Line could most certainly use improvement in frequency, reliability and speed. Although the schedule is fairly frequent, the reliability of that schedule is poor, leading to common cases of train bunching and overcrowding. The speed is well, ..., legendarily slow. The at-grade segments average between 6 and 9 mph normally, making them slower than a typical human runner. So there is definitely room for significant improvement. But I doubt that Jarrett is thinking about systems like the Green Line -- which, despite its problems, does attempt to have good frequency and attract strong ridership. He is thinking of newer systems such as Salt Lake City's S-Line that is both slow and infrequent.

Steep stairs to get on and off board:
arduous for people with mobility impairments

But the Green Line does demonstrate a point that qualifies as a slight quibble with Jarrett's argument. Yes, it is true that service levels are the most important feature of a transit system. But there is an infrastructural component that I think also qualifies as a form of "service" and that's accessibility. You could build the most wonderful light rail system in the world, with a train every few minutes that takes you speedily to your destination, but it would be totally useless if you had to cross a dangerous high-speed roadway just to get to a station. Or if the station was designed with so many fences and obstacles that just getting to the platform is a journey in itself. Obviously this is a huge issue for people with disabilities, and 24 years after the passage of the ADA we're still far behind where we should be. But accessibility is also an issue for people without disabilities. First of all, just about every person born in this world will probably deal with some kind of mobility limitations of the course of a lifetime. Whether it be broken bones, aging knees, arthritis, or anything else, it still shouldn't disqualify you from being able to access public transportation. And even if you are fortunate enough to be in perfect health, you are still probably less likely to use a service if the access path to reach it is long and arduous.

Furthermore, all these problems are exacerbated if you have to climb steep stairs to get on or off the vehicle. And if you have to push and shove through a crowd just to get to a seat -- or even merely an open space for standing. And then push just to escape from the tiny front door, and be forced to climb down those steep stairs again.

I bring this topic up because the Green Line has a serious problem with poor accessibility, both for people with and without disabilities. And it's completely unnecessary. In theory, the surface Green Line could be the most accessible of all the segments of train lines in Boston. The platforms are at the same grade as the sidewalk, which means no stairs nor elevators needed. The tracks naturally guide the vehicle close to the platform edge, nearly the same place every time, without any additional effort from the driver. We have the technology that makes low-floor vehicles possible. Modern fare collection systems can work at any door. Using the Green Line could be as easy as walking through the entrance of a building.

But in practice, it's not. People with disabilities consistently rate the Green Line as one of the worst to use. Everyone else just seems to put up with the problems. The MBTA actively makes life worse for its customers by choosing the most bizarre and inefficient operating procedures. I understand that there are fiscal constraints preventing the T from replacing the existing high floor vehicles (which are also, alas, the only reliable vehicles in the fleet). I understand that there are historical constraints in the tunnels preventing the T from purchasing widely-used, modern vehicles (although I think they could try harder to fix some of these longstanding issues). But there is really no excuse for refusing to open up all of the doors of a train at every single station (especially the low-floor doors). There is no excuse for failing to implement the modern fare collection method that SF MUNI now deploys system-wide, and that even the MBTA was going to adopt until they mysteriously decided to give up trying, a few years ago. And there is no excuse for designing stations in maximally obnoxious ways that seem to be catering more to the desires of speeding car drivers than to the needs of transit riders.

A cage for transit riders, surrounded by wide lanes for speeding motor vehicles.

Here's my vision for the MBTA Green Line going forward: doing all the little things right, the way they should have been done years ago.

• Consolidate stations that are within a 2-3 minute walk of each other.
• Continue the process of making every station ADA and AAB compliant.
• Maximize pedestrian accessibility to stations:
• multiple points of access,
• making it as easy as possible to walk from all directions to the station platform,
• and creating a street environment that is pedestrian-friendly all around.
• All doors open at all stations. No excuses, no delays, no wasting time. No more forcing passengers who might have disabilities to mount those steep stairs and push into the vehicle.
• Pre-payment on the platform and/or CharlieCard kiosks installed at every door.
• Every intersection should have a form of signal priority installed that minimizes signal delay for Green Line trains as much as possible.

These reforms are relatively cheap up front and will save money over the long run. And by relatively cheap, I mean compared to the cost of massive capital expenditure such as extending the subway. Plus, putting the train underground causes you to lose that accessibility advantage. And anyway, it's not necessary to do expensive grade separation in order to achieve significant service improvement. We're more than capable of doing much better with the existing tracks.

About the upcoming annual Green Line forum on May 28th: recommendations and a call for action

Senator Brownsberger is hosting another Green Line forum this upcoming May 28th, 6pm, at the BPL Copley Rabb Lecture Hall. Hopefully the room will be packed with riders able to demonstrate the importance of the Green Line and fixing its numerous problems. In past years, the experience has been interesting. A good sized crowd showed up last year. Several of the speakers made some very good comments. I remember the first person to speak was a father, who brought his young son, they both stood up at the front of the room and he called upon the MBTA officials to implement signal priority: why should a train filled with hundreds of people have to wait for a few cars?

On the other hand, several of the speakers made some truly bonkers comments. Like one older gentleman, who said he had been riding for forty years, but for some reason was upset at the fact that he saw empty 2-car trains sometimes. The MBTA official who responded actually handled this one correctly, and she pointed out that an empty train in Brighton could easily be a full train further down the line.

"off-peak"

Unfortunately, the MBTA did not handle it correctly when another crazed speaker whined about seeing one or two people sneaking in the rear doors. The MBTA continues to punish all riders collectively, despite having no evidence to back up their reprehensible "front door only" policy. Refusing to open the rear doors causes massive delays and train bunching, but the MBTA clearly has no respect for the paying customers, nor for their own wasted money on overtime as delays pile up. The correct response would have been to say something like: "the importance of following schedules and keeping dwell times low far outweighs the possibility that someone might sneak in the rear door, and anyway, we are going to implement proof-of-payment soon!"

Ultimately, what came out of the process last year was a letter from Dr. Scott that briefly responded to a few issues but made very few changes. The real headline grabber was the announcement of Green Line tracking in 2015. There were a few passive changes to signalization: I noticed the change at Packard's Corner before I read the letter, actually, so I suppose it has helped a tiny bit. But that was it. We are still waiting for the public process on station consolidation, although I have heard more rumors of it brewing lately. There has been no movement on the signal priority front, despite its great potential, and despite the fact that Huntington Ave is fully modernized and ready to go anytime the T wants to try (unlike Comm Ave). And all-door boarding/proof-of-payment seems to have disappeared off the agenda entirely, although it has huge potential for accessibility and schedule-keeping improvement.

Commonwealth Ave reconstruction phases

For this year, I think we can do better. Phase 2A of the Comm Ave rebuild is going to be funded starting in October, and that will open up all kinds of possibilities, because it involves reconstructing a segment of the "B" branch that has the most closely spaced stations. I would say that the items we need to focus on pushing the MBTA to consider are:

• Station consolidation, as described in this blog post. We need to bring the station spacing up to modern standards, which is closer to 1200-1400 feet than the current 725 feet. This will help improve speeds and simplify operations. It also reduces the number of stations the MBTA has to bring up to ADA standards, and it also frees up space for use by pedestrians and bicyclists on Comm Ave.
• Signal priority to help reduce the schedule unreliability caused by capricious traffic signalization. This does not have to be as preemptive as Houston's in order to have a positive effect, although it would be appreciated!
• All door boarding, if not full blown proof-of-payment. There's a few ways to go about this that don't require proof-of-payment to be implemented. For example, fare inspectors could stand in the back of random Green Line cars and ask to see the pass of anyone who steps in the rear. I know this is feasible because they used to do it on a regular basis! In the future, I think the T would be best served by implementing MUNI-style proof-of-payment, though, which basically is cash-up-front and CharlieCards-at-all-doors. Then the T should also encourage the purchase of monthly/weekly passes as much as possible. This approach is the best for both revenue protection and schedule protection, in my opinion.
• Easy access to stations and platforms. Unfortunately, the MBTA has a terrible habit of destroying accessibility whenever they "modernize" a station. If you look at the rebuilt stations on the Green Line, many of them are harder for a pedestrian to access than the older asphalt strips. So, while they abide by the ADA legal requirements, they do so in a manner that is as obnoxious as possible. This is insane. The MBTA needs to recognize that station access time is part of every rider's journey, and optimizing it is just as important as getting signal priority or other improvements done right. In short: every MBTA platform should have at least two exits/entrances: one at either end of the platform, with crosswalks (signalized or not) to the sidewalk. Walking to the station from any direction should be achievable with as straight-line a path as reasonably possible. Nobody should ever be forced to walk 200 yards out of their way to access a station because of a stupidly placed fence. That's valuable minutes wasted (and even worse for seniors or the disabled) that could determine whether someone misses a train, or even bothers to ride at all!

The Commonwealth Ave jail: the punishment inflicted by the MBTA on riders

My suggestions spring from a simple philosophy: riding the Green Line should be as easy, accessible, and reliable as possible. Everything I advocate for comes from that principle. I know that people like to dump on the Green Line, but it actually has a lot of potential that is simply wasted by the MBTA. Fact is, the Green Line has a major advantage over buses and streetcars: it has dedicated lanes (mostly). And the Green Line has a major advantage over subways and elevated trains: it is on the surface, which should make access easy if the MBTA would only allow it, no stairs nor elevators required! If you consider door-to-door journey time, then with signal priority, all-door boarding, and station consolidation combined with convenient station accessibility, the Green Line could be quite competitive with full blown subways.

I hope that people will show up on May 28th and advocate positively for improvements to the Green Line; improvements that will truly benefit the 30,000+ people who ride it every day. You are welcome to use any of my suggestions, and I look forward to hearing some of yours as well.

Is Houston more progressive than Boston in transportation?

Okay, gotcha: not really, it's still very much a land of sprawl and crazy-large highways. But I read this article last month and then had a chance to see some of it for myself.

In fact, Houston's core neighborhoods grew around a 90-mile streetcar system, and the city has a higher WalkScore than Austin. "Houston is amazingly more progressive and more concerned about things like quality of life, walkable neighborhoods, and bike infrastructure than people realize," says Susan Rogers, a professor of architecture at the University of Houston.

After visiting, I have to concur, although they do seem to have a long way to go yet. I had to drive myself more in those two days than I did in the last two years combined (or more). I want to talk about one technical area in which Houston is doing significantly better than Boston: at-grade transit.

METRORail at Fannin South station

METRO's light rail line is just over ten years old so it does not have the venerability of Boston's Green Line. It does, however, have a lot of details implemented correctly, and it shows. I was able to ride it one evening, to get dinner downtown, and I made some observations along the way.

METRORail opened as a 7.5 mile line in 2003 and has just been extended another 5.3 miles in December for a total of 12.8 miles. It is almost entirely at-grade, although there are a few places where it ducks under or flies over other roads and infrastructure. Here's the main points that it does really well:

• Signal priority or outright preemption at every single intersection it crosses. As the train approaches, lights flash, traffic signals change, and a sign lights up telling drivers to get out of the way of the train. In some cases, they use railroad crossing arms, in other cases, just ordinary traffic signals.
• Proof of Payment ticketing with modern, touchless fare card technology. I got a "Day Pass" and boarding was as simple as waving my card at a box on the platform, then hopping onboard using any door I wanted. Dwell times were consistently low, approximately 20 seconds per stop before we started moving again. Accessibility is great.
• Decent station spacing. Actually, average spacing is about 1/2 mile, which is a bit far, but there is some significant variability in that. The denser areas have shorter station gaps. At least one infill station is planned, Central Station, to assist with the upcoming expansion projects.
• A transit mall downtown, where private vehicular traffic was limited or excluded. The train had clearly been prioritized over the automobile in terms of space.
• Automatic cap on fare paid per day: with the "Day Pass" I pay $1.25 for the first trip, $1.25 for the second trip, $0.50 for the third trip, and nothing for all remaining trips of the day. The MBTA's Day Pass is $11.00, almost thoroughly useless, unless you are sure that you are taking more than 5 trips that day.
• Houston did not feel the "need" to put an awful fence down the middle of the entire right-of-way, which is a big difference from the way Boston's transportation agencies treat us ordinary folks on foot.

The result is that Houston's METRORail has a one way trip time of 50 minutes meaning that it manages a respectable and reliable average speed of 15 mph without the help of expensive grade separation. By comparison, according to the published schedule, or Blue Book:

• Boston's Green Line "B" plods along at about 8-9 mph on average, unreliably.
• The "C" branch goes 8-11 mph depending on time of day.
• The "D" branch, almost fully grade separated, manages to average 15-18 mph.
• The "E" branch does 9-12 mph, on the schedule.
• The SL5 "bus rapid transit" goes 8-10 mph as scheduled, and is slower in reality.
• The heavy rail portions of the MBTA average 19.4 mph in general, and
• The NYC subway system averages 17.4 mph overall.

Through sheer operational competence, Houston has managed to create a surface transit line, crossing many intersections at-grade, that is time and reliability-competitive with expensive grade-separated subways. Very impressive. This is an accomplishment of which the city should be very proud.

And it doesn't end there. Apparently, the original line was constructed for about $325 million in 2003 (including purchase of trains). That's about $50 million / mile in today's dollars. It has achieved approximately 36,000 rides per day, making it the 2nd busiest per-mile in the country. And at $9,000/daily boarding, it's a bargain in human terms.

So while Houston will never match Boston as a city in my view (although I wish them the best), I think we could really stand to learn quite a bit from METRO. Houston is supposedly the home of highway-centric thinking, and yet, they have a gem of a light rail line that could be held up as a model for the entire country. It's good transit in a red state, done cost effectively and operationally efficiently. METRO went up against what must have been an extremely strong motorist lobby... and won. Meanwhile, here in Boston, where we are supposedly so public transit friendly, we can't even get our city to support signal priority, all door boarding, or even respect a bus lane. What is wrong with us? Why are our public officials so cowardly? What are they afraid of? It cannot possibly be worse than the Texas Dept of Transportation.

The need for station consolidation on the MBTA "B" branch, in one chart

Update: MBTA announces station consolidation public meeting, Oct 23rd.

Original Article:
A little while back, BU put together a Transportation Master Plan that included some detailed ridership data about the MBTA Green Line "B" branch. I somehow missed this appendix while looking through their master plan in the past. Thanks go to Eric Fischer for alerting me to my oversight.

The data include hour-by-hour breakdown of boardings, alightings, and line volume (the number of people riding through) for each of the surface stations Blandford Street through Warren Street, taken on a Fall 2010 day. It occurred to me that a station's importance is related to the number of people who use it, versus the number of people who would prefer to ride past it. This is also tied to the relative proximity of the stations. Multiple, closely spaced stations will divide up potential ridership and therefore, will mutually reduce the importance of each such station.

The four stations in the scope of the upcoming Commonwealth Avenue Phase 2A street rebuilding project are very closely spaced. They are some of the most closely spaced stations in the entire system, as they are placed on four consecutive city blocks approximately 730 feet apart on average. That is a 2-3 minute leisurely walk between stations. Perhaps only Back of the Hill and Heath Street are closer.

The diagram above is drawn to scale, and it shows how the stations are spaced relative to one another. Above the station names is a bar graph which shows the relative importance of each station, as measured by the number of people who use the station (boarding, alighting) divided by the number of people who ride through the station. It should come as no surprise to any frequent user of the "B" branch that Harvard Avenue is the most important station, by far, and that the four least important stations are: Babcock Street, Pleasant Street, St Paul Street, and BU West; the last being the most underutilized.

I believe that this diagram makes a strong, visual case for station consolidation during the upcoming Phase 2A project, in addition to station relocation to better accommodate signal priority. I would like to see the MBTA begin a public process, much like they did ten years ago, to work on implementing efficient station spacing for this section of the Green Line.

In addition to improving the experience for about 30,000 people, a shorter round trip time will save resources for the MBTA. If the scheduled round trip time for a train can be reduced by 6 minutes, then that means one fewer train is needed to operate the same peak schedule. That train can then be put to better use in other ways: to split it into more 3-car trains, to help bring back 5 minute frequency, or to send it out for much needed maintenance.

Even more savings are available if the MBTA finally implements all-door boarding and transit signal priority, but that's another discussion.

A quick note on the gap between BU West and BU Central: that space is mostly occupied by the Mass Pike trench, currently. The overpass of the Pike will be reconfigured as part of Phase 2B, and then I believe that BU has some air rights projects in mind. If station consolidation is properly implemented in Phase 2A, and if BU ever builds over the Pike, then it may make sense in the future to relocate BU Central further west. But until then, the most pressing issue is figuring out how to fix the Green Line problems within the scope of Phase 2A.

Is fare evasion really a problem?

(continued from previous post)

Something that caught my eye in the MBTA ROC report was that it was the first time that I've seen anyone take a real crack at estimating fare evasion. Usually the T just makes up numbers. In this case, it was CTPS that supplied the data, which is found in Appendix D. The ROC is proposing that the student pass program would eliminate the "need" for the "front door-only policy" that is currently in effect. I don't think that the "front door-only policy" was ever a good idea at all, student passes or not, but let's take a look at the data that we finally get to see.

A few notes: This table claims that FY12 trips on Light Rail were at 52,418,000 and Heavy Rail 128,803,000 which, if true, represents a decline of over 20,000,000 trips in each mode, down from what's shown in FY11 NTD data. That seems strange, even considering the fare hike. On the other hand, Bus and Trackless Trolley ridership is up by a million or so.

The table at the bottom shows "Non-AFC" Light Rail trips as being about 12% of all Light Rail trips, but there's no rationale given for that 12%. It's hard to reconstruct this number without knowing how many of the trips counted came through fare-gates and how many were surface-originating.

There's a similar problem when comparing the Total "Evasion" count to Non-AFC Trips, which is about 32% but I have no idea where that proportion is sourced from either.

The average fare is scaled by a factor of 1.25 -- presumably due to the fare hike of last year, and because the average fare is otherwise being determined from FY11 data.

The top table seems to indicate that the rate of people using the rear door is about 9% of riders. Caveat: this doesn't mean they were not paying, it just means nobody checked -- the MBTA's old "Show'n'Go" policy encouraged folks to use the rear door but they would be counted as "DNP" under this category.

At the bottom, there is a handwritten note that $912,000 was lost "from rear door" and this is quoted in the report as "lost approximately one million dollars per year." Putting aside all the other concerns from above, let's assume this is true. The lost million dollars sounds pretty significant, but let's put it in context. The table claims that there were 52.4 million trips on Light Rail at an average fare of $1.21 per trip. That means a total revenue of $63.4 million. If one million in revenue was lost, then that means a loss rate of 1.5% which is significantly lower than 9%, and even lower than past estimates of 2-4%.

In pretty much any system, a 1.5% fare evasion rate would be regarded as a resounding success. Nothing is perfect, and fare collection has very significant costs. Trying to pursue the last 1% could easily cost more than it's worth. And that's assuming that the revenue was "lost" which is not necessarily true. It could be mostly people with passes.

If these numbers are actually correct (admittedly, I am starting to doubt) then there is no reason to pursue fare evasion as an issue. It's a total waste of time and money that will actually cost more than it will collect. And it also harms the riding public, by slowing down trains, bunching them up, dragging down performance and schedules. And that costs real money: if extra trains are needed then you're talking over $200/vehicle hour just to keep on schedule. And that doesn't count the time-cost to passengers on board, something which T management never seems to think about, because they treats their customers like their time is worthless. Likely a holdover attitude from the bad old days of "managed decline": when the T was supposed to die in favor of universal car ownership.

Even if the fare evasion rate was doubled to 3%, that would still not be significant enough to worry about. When should it be worried about? That's easy: when the cost of enforcement is lower than the cost of loss. And the first step towards understanding that is getting real data.

Moral grandstanding about fare evasion is selfish and foolish. Show me the numbers, show me the money, don't waste my time.

Larger vehicles should have fewer stations-per-mile

On the topic of station consolidation along the Green Line, one thing I've always noticed is that the 57 bus tends to outpace the "B" branch on the shared corridor except in the case where the bus has to make every stop. The train makes every stop on almost every trip except late in the evening when demand is lower. The difference can be quite stark: I've made it from Park Street to Harvard Avenue in under 20 minutes after midnight, but I've been stuck for over 50 minutes on the same leg during the afternoon rush, on what should nominally be a 25-30 minute trip.

The reason why I (and others) advocate for station consolidation is to reduce the fixed overhead associated with making a stop. But I think there's a more general case to be made. Let's look at the capacities of the vehicles. The planning capacity of a typical MBTA bus is 54 people (75 at crush load) and the capacity of a typical 2-car Green Line train is 202 people (468 at crush load). The train could easily be carrying between 4 and 6 times the number of people as the bus.

Now consider two stations that are too close together (for example, Saint Paul Street and Pleasant Street). There are people who will prefer one or the other station for small reasons and will be inclined to ring the stop request bell at that station. On the train, the probability is much higher that a person will ring the bell for the first station and also another person will ring the bell for the second station. On the bus, with fewer people onboard, it is likelier that one or the other can be passed up.

My experience bears this out: the Green Line rarely skips stops under normal service; the 57 bus will almost always be able to skip some stops even at the height of rush hour.

That accounts for alighting, but what about boarding? The likelihood that someone will be waiting at the station and flagging down the vehicle is related to the "strength" of the route: how well it attracts riders. The top 3 characteristics that make it attractive to riders are: frequency, where it goes, and perceived reliability. The Green Line is scheduled to run at higher frequency than the bus during its entire span. In addition, the train seems to draw more riders than the bus for a number of reasons, including: it goes downtown, it has a larger presence in the minds of riders (unfair but true), and higher perceived reliability (at least for those folks without smartphones). Again, if you have two closely spaced stations, then for small reasons people will prefer one or the other and the train will likely have to stop at both. But in this case it has less to do with capacity (except, perhaps, if riders fear they may be passed up by a full bus).

So to wrap it up, I think there is a natural bias towards longer station spacing (up to a reasonable point) for larger capacity vehicles, where the stop request bell is going to be pressed virtually all of the time anyway. In addition, people tend to be willing to walk further to faster, higher quality service, and spacing out stations further will speed up the Green Line a bit. Building higher quality platforms with good access at both ends (something the Green Line sadly lacks, but ADA requires) will also help shorten those walking distances while not sacrificing service quality.

Light rail and traffic

Streetcars on Brighton Avenue 1940 

A note on Brad Plumer's article Do light-rail systems help cut down on traffic?. Anyone familiar with the Downs-Thomson paradox and related concepts would understand that light rail or any public transit system is not a "congestion reliever" in the simple sense that most people use. That's because in most congested contexts, any driver who decides to leave the car at home and switch over to transit will likely be replaced by another car on the road. This is not a hopeless outcome however--where before there was one person able to travel, there are now two. So the overall level of transportation activity has increased even though road congestion has remained the same, in this scenario.

Public transit in dedicated lanes can enable more people to travel despite congestion on the roads. If you want to actually tackle the congestion itself, then as Brad points out, road pricing seems to be the only option that has been proven to work. But I want to get to his last point which is this:

The other point is that mass-transit systems can lessen road traffic, but only if they’re part of a broader shift by a city to move to denser development. Researchers have found that people living in more compact cities with better transit options do drive less overall. But that shift doesn't happen overnight. And not all light-rail systems are even built with this sort of development in mind.

Boston happens to be one of those places with "light rail" and denser development built up along those corridors, thanks to the fact that most of it was built before zoning became a weapon used against cities. So if you take a look a Commonwealth Avenue you find something interesting. Despite the fact that the road has 6 lanes of travel (4 inner, 2 outer), MassDOT records very low traffic levels on the order of 12,000 AADT. By comparison, Washington Street in Brighton Center carries 14,500 AADT with only 2 lanes, and Harvard Avenue is all the way up at 18,100 AADT with only 2 lanes as well. Why isn't Commonwealth Avenue more like Brighton Avenue which has 4 lanes and sees volumes of 23,000 to 28,000 AADT?

First, for a variety of reasons, Commonwealth Avenue (in Allston/Brighton) is not a heavily used through-route, unlike Harvard Avenue or even Washington Street, so the traffic on it is largely coming from or going to nearby places. Second, although the development along the avenue is at city levels of density (~80-120 dwelling units/acre), because it grew up around the streetcar, there's not as much parking as such quantities of units would bring under current zoning codes. So trips are much less likely to be made by automobile. This seems borne out by the fact that the current "B" line is the busiest branch (~30,000 boardings/weekday) and that just over 50% of residents who live along this corridor get by without access to a car.

So in congruence with Brad's point, I think that you have here an example of how a century of streetcar service, combined with the long-ago shift to denser development, has lessened road traffic in the present day. Now the question for many developing light rail systems is: can you also achieve that, and perhaps on a shorter timescale?

Transit signal priority

Following onto my last post about station elimination and consolidation: The topic of transit signal priority comes up frequently when discussing improvements to the Green Line. It was prominently discussed at last month's Green Line meeting. I went and did some background research on it.

What is transit signal priority (TSP)?

Example phases in a traffic light cycle (simplified)

Transit signal priority is the application of subtle changes to traffic light timing in order to assist the passage of transit vehicles. Broadly speaking, there are two categories: passive and active. Passive priority is static and predetermined: for example, changes to the timing of traffic light phases, or to the transit schedules. Active signal priority occurs dynamically, triggered as the system detects the approach of a transit vehicle. I will be focusing on active TSP.

TSP should not be confused with "preemption" which is the abrupt interruption of normal traffic signal functioning. Preemption is used for safety purposes primarily: to assist emergency vehicles, or to clear a railroad grade crossing. The key difference is subtlety: traffic signal priority should be almost completely unnoticeable to observers.

Who is using TSP?

In the United States and Canada, over twenty agencies report using TSP, including but not limited to: Los Angeles Metro, Houston MTA, Sacramento RT, Pierce Transit (Tacoma), TriMet (Portland), SEPTA (Philadelphia), PVTA (Springfield, MA) and Calgary Transit.

Some examples in other countries include: Zürich, Paris, London, Sheffield (UK), Amsterdam, Hannover (Germany), Sapporo and Curitiba (Brazil).

Why do TSP?

The primary benefit of TSP is enhanced reliability of schedules: better maintenance of headways and less bunching. One of the biggest causes of variability is the unpredictable delay caused by traffic signals, compounded over the course of many intersections. TSP makes it possible to avoid the worst-case delay. A secondary benefit of TSP is a slight reduction in average trip time: less waiting at intersections. Another benefit is a potential reduction in operating costs for the route; saving money or boosting resources elsewhere.

To see that, you must think about a transit route as a loop -- even linear routes must double back and return vehicles to their starting position somehow. Normally, after a vehicle returns to the beginning, it is allowed to rest for a certain period of time called the "layover." The driver gets a break, or changes out. If the vehicle is running late, but not too late, then the layover is shortened in order to "recover" the schedule.

Agencies build substantial "recovery time" into the layover time of a route, usually by tacking on a "padding" percentage of the round trip time. The percentage depends upon the reliability of the route: the goal is to minimize the probability that a vehicle finishes its round trip so late that it has exceeded the layover time allotted. So if TSP makes the route more reliable, then the layover time can be reduced.

Whether through increased reliability, or reduced round trip time, if the overall time can be reduced by enough, then fewer vehicles and fewer drivers are needed to operate it -- a major cost savings. To give an example: the MBTA Blue Book 2010 reports that in morning rush hour the "B" branch of the Green Line requires 20 trains which are supposed to be spaced at 5 minute headways. This means that trains can leave Boston College over the course of 100 minutes until a returning train must be reused. The Blue Book also states that the scheduled time to reach Government Center is 45 minutes, and the scheduled return time is 43 minutes, for a scheduled round trip time of 88 minutes and a layover of 12 minutes. That implies a 13.6% padding.

Now suppose that the padding could be reduced to 7% which happens to be the Swiss standard. That would imply a 6.2 minute layover, and at 5 minute headways, only 19 trains would be needed to provide morning rush hour service on the Boston College line. The NTD factsheet says that light rail costs $216/vehicle hour to operate here, so removing just that one train from just that one shift saves approximately $120,000 a year.

Even if 7% is considered to be too little padding for other reasons, the combined travel time and layover time savings could easily add up to 5 minutes or more, producing the same operating cost reduction. And applied to all shifts you might even see savings add up to millions of dollars per year which can be put into other operating improvements.

How does TSP work?

There are a few techniques that are generally applied to achieve active signal priority. Any combination of them may be deployed, depending on the conditions at each intersection. Vehicle detection methods must also be selected which are capable of providing enough notice of arrival to the traffic light controller. Such methods can be as simple as an induction loop in the ground, an optical sensor, or even information obtained from GPS satellites used to model the real-time schedule.

Green extension keeps the signal green for a short while longer to allow a detected transit vehicle enough time to pass a light that was about to turn red.

Early green hastens the expiration of the red light so that the detected transit vehicle can get moving as soon as possible.

Phase insertion waits for the next moment in the cycle that all conflicting traffic is stopped and then takes a few seconds for a special "phase" which gives the detected transit vehicle an opportunity to proceed.

Phase rotation changes the ordering of interchangeable phases so that the detected transit vehicle can proceed sooner rather than later. The best example is a left-turn-only phase which normally occurs before straight-through traffic goes: it can easily be "rotated" to occur after the straight-through phase instead.

What are the downsides?

Deployment of TSP should be transparent to the typical road user. Unless they are looking closely, they shouldn't notice anything different; although some techniques are more obtrusive than others. Green extension is probably the least noticeable intervention. On the other hand, early green has to allow enough time to safely clear the intersection: which can be difficult in the case of pedestrians. Phase insertion may be noticed by those waiting for the next phase, but it is a fairly short delay. Phase rotation may confuse those who have memorized the light patterns; but so would any change (Zürich chose to randomize such phases before implementing signal priority, to prepare the public in advance).

The North American systems studied in-depth by the FTA did not find any significant delay experienced by the non-priority traffic, but systems in the past have failed due to improper planning, so it is important to study the design. However, even if there were significant delay to vehicles, that is not the correct metric to be using. Traffic engineers infamously use "level of service" to grade intersections by vehicle-seconds of delay even though this kind of thinking is notoriously unsuitable for city streets with many different kinds of users. Instead, transportation departments ought to be thinking about optimizing the safe "movement of people" instead of the "movement of vehicles." And in that respect, even if a signal priority system does cause some measurable delay to non-priority vehicles, it needs to be evaluated by the overall effect it has on people, not vehicles.

For example, suppose the installation of TSP at an intersection causes an average of 5 seconds additional delay to 36,000 non-priority vehicles, but also manages to reduce average delay by 15 seconds to the transit vehicles carrying 30,000 people a day. Assuming an occupancy rate of 1.2 persons per car, that's 216,000 person-seconds of delay to non-priority traffic. That sounds pretty significant until you realize that it is massively outweighed by the 450,000 person-seconds saved by the riders. And 36,000 non-priority vehicles is very high; in most cases along the Green Line the number is much, much less.

A transportation department with its priorities straight would consider person-seconds the metric by which to optimize, not vehicle-seconds. And "level of service" is not a valid metric to use on city intersections because it does not make consideration for people, traveling in all modes, with or without vehicles.

Further reading.

• FTA Handbook on Transit Signal Priority
• Notes on Transit Signal Priority
• BusMeister: Intro to TSP
• Guidelines for the Planning and Deployment of Emergency Vehicle Preemption and Transit Priority Strategies