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.

Downtown Boston is Busmageddon? Really?!

Update: A shortened far less ad hominem version of this has been published in Commonwealth Magazine.

Every so often an article comes along which is so inane, so poorly researched and so utterly stupid that it requires a line-by-line refuting.

The article in question, which has a dateline of March 31 so I’m assuming it’s not an April Fools joke, is:

End downtown Boston’s busmageddon Add reworking bus routes to the MBTA’s to-do list

Oh boy.

The first four paragraphs go on about how people are taking public transit in Boston. Fine. Then you get to paragraph 5:

We need a comprehensive policy regarding usage of the public way. 

Good! We agree. We do need a comprehensive policy regarding usage of the public way. Right now, approximately 75% of the roadways in Downtown Boston are dedicated to automobiles. Another 20% are sidewalks, and 5% are bike lanes. Yet the number of cars is decreasing (to quote the author two paragraphs earlier), and the majority of people coming to Boston don’t use cars. So why do cars (as usual) get the vast majority of space? Why should they get all the real estate if they only account for a minority of travelers? Who knows.

Loading must be done during limited hours, as is the case in other great cities.

Loading? Fine. That’s a halfway-decent point. Care to elaborate? (Apparently not.)

To keep the city from devolving into perpetual gridlock, we also must address tour buses and MBTA buses downtown.

Boston has no through bus routes through downtown, the only city in the country to do so. Perpetual gridlock? How much of the gridlock downtown is caused by buses at Haymarket (in their own terminal, mind you), the Franklin-Federal loop, the Silver Line and a few other sundry routes, as opposed to, say, tens of thousands of cars trying to ply narrow streets downtown? Tour buses? Sure, get rid of those space-hogging menaces. But getting rid of a few MBTA buses? Please.

And what of these other great cities? What do they have in common? London? Bus lanes. New York City? Bus lanes. Minneapolis? Double bus lanes. Boston? Well, we have the Silver Line, but it barely has bus lanes downtown.

Let’s get the buses off of our streets so that pedestrians and bicyclists can be safe.

Red herring! Red herring! Red mfing herring! T Buses account for, oh, maybe 2% of traffic downtown. Maybe. Probably less. Certainly far less than any other city in America. Take a look at Bostonography’s great bus speed map (a screen capture to the right). Notice that there is actually a gap in Downtown Boston with no bus service. Compared to nearly any other city in the country, Boston has less bus service in its downtown. Other top bicycling cities like Minneapolis, Seattle, San Francisco and Portland have many more buses, yet no one is demanding that buses be pushed to the outskirts there.

Yet buses are menace to pedestrians and bicyclists? Should we consider doing something about the other 95% the traffic downtown? The cars? Or are pedestrians and cyclists somehow immune to them?

As Doug Most reminded us in The Race Underground, Boston constructed the first subway tunnel in the late 1890s to get trolleys off the street; we can certainly do likewise today by making good on the commitment to a tunnel connecting South Station with the Silver Line spur that heads to Dudley Square.

Oh, good lord. Yes, we could spend $2 billion to build the Silver Line Phase III tunnel. Somehow this would solve all of our transportation problems. Except for the buses going to Haymarket, South Station and all of the express buses. It wouldn’t really get any cars off the street (although by his logic, cars on the street aren’t the problem). It would create a low-capacity, slow route that could be replicated for 1/100th of the cost with signal priority and bus lanes. But that might impact cars and their drivers dense enough to think the best way to Downtown Boston is to drive.

There is also no reason why people wanting to go to Salem should have an express bus waiting for them around the corner from Macy’s …

Most people going to Salem don’t wait by Macy’s: they wait at the Haymarket bus station. (Also, if you’re actually from Boston, it’s Jordan Marsh. But I digress.) It’s not perfect, but it’s covered, and the buses pull in to a busway to load and discharge passengers. But so what if they do? Downtown Crossing is right in the center of the city. If we make people from Salem walk ten minutes, or squeeze on to an already-over capacity subway train, they’re more likely to say “the hell with it” and drive. Do cars cause congestion? Or just the 16 buses per day that run from Salem to Downtown Crossing?

… nor should city street patterns necessitate that a bus make a left turn from a right lane to meander through downtown streets to get to the Mass Pike.

The 500-series buses do load on narrow streets and have to reach the Mass Pike. Why? Because they are basically the replacement for the other two tracks of the Boston and Albany railroad. When the tracks were paved over for the Turnpike, the 500-series buses replaced local service there. There were proposals in the ’40s to run service similar to the Highland Branch from Park Street, out the Tremont Street portal, on to the tracks parallel to the current Worcester Line, and out to Allston, Brighton and Newton (huge file here). Instead, we had got the Turnpike, which express bus service, which is express until it sits in Turnpike traffic. If you hadn’t built the city for cars, you wouldn’t have to worry about the buses; the streetcars could be underground in that aforementioned tunnel.

Large buses making wide turns on narrow downtown streets, even more narrow because of mounds of snow, clog the streets and imperil the safety of the public. 

Large buses clog the streets? What about parked cars? What about moving cars in traffic? How about we eliminate downtown on-street parking and give the buses their own lanes, and make sure the mounds of snow are removed from them. And do only the buses imperil public safety? No pedestrian has ever been killed by a car, right?

We should eliminate bus lines which make no sense and relocate the terminus of lines now heading downtown to South Station and North Station …

We have an intercity bus terminal at South Station. It’s at capacity. There’s no way to add T buses in to it. And it’s a five minute walking transfer to the already-over capacity Red Line.  The current routes that could conceivably go to South Station aren’t perfect, but they seem to work. Maybe we should create a network of downtown bus lanes instead? Cyclists and pedestrians would know where the buses would be, and it would help buses move through downtown more quickly.

And North Station? That’s why we have the Haymarket bus station. It has room for buses and easy connections to the Orange and Green lines. Perhaps when the Government Center Garage is rebuilt, it will include a better bus terminal and connections, and bus lanes across the bridge to rebuilt bridge to Charlestown.

… where there is access to underground transit, commuter rail and the interstate highway system.

Yes, there is access to underground transit. That’s all well and good. Except that underground transit is growing faster than other parts of the system, while struggling with decades-old equipment and overcrowding. Most downtown buses operate like commuter rail: they go from the suburbs to the city. There’s little need for passengers to transfer to commuter rail, rather they want to transfer to their place of work. Instead of dropping people at the outskirts of downtown, we should have more central bus routes that balance operational efficiency with getting people where they want to go. Give as many people a one-seat ride and a comfortable place to wait, and they’ll be more likely to ride.

Even as we eagerly await the Red Sox return to Fenway Park, and the melting of the last mounds of snow (most likely in that order), we should be thinking – and planning – ahead.

If you really want to encourage safer streets, getting rid of transit is certainly not the way to go. Planning ahead will certainly be important, but let’s plan the right way. The right way might be a congestion charge, to get cars off the streets at peak times. The right way might be to build bus lanes so that bus riders have seamless trips through downtown to their destinations. The right way might be to require tour buses, an actual menace to pedestrians and cyclists which provide no actual public good, to stick to certain streets, routes and times.

Or the right way may be to raise the goddamn parking tax. Right now, Boston has one of the lower parking taxes around. Because parking is very much constrained, it is not subject to the whims of supply and demand: a daily tax on parking spaces would likely not even affect the consumer price much, but move some of the profit from the property owners to the city. Given the negative externalities of cars on city streets, and the fact that most people utilizing parking spaces are from out of town, the city should raise taxes and use the money to improve public transportation, perhaps starting with, that’s right, buses.

So the right way is not to demonize public transit and couch it in the guise of pedestrian and bicycle safety is disingenuous at best. Ignoring the fact that nearly all traffic downtown is made up of cars driving on subsidized roadways and offering debunked solutions is a farce. Note the red X on the map to the right. It shows the location of the author’s office in relation to the 448/449/459 and 500-series bus routes in Boston. What are the chances he’s just rubbed the wrong way by seeing a bunch of buses outside of his office? You know, buses that make it really convenient for people to get there?

Let’s build better bus facilities. Lincoln Street and the Surface Artery which all the 500-series routes follow have plenty of room for a bus lane (Lincoln Street has two lanes of traffic and two of parking). Federal has parking on both sides. Why not take some of that space which is making the streets narrow and dangerous and use it for buses? It might make it a little less convenient for Mr. DiCara to drive there. That’s probably his real beef.

And Commonwealth Magazine should be on the hook, both for not fact-checking this article, and for letting someone with no actual expertise in the industry write it in the first place. Just because he saw a lot of buses at Lincoln and Summer one morning doesn’t mean that they’re the problem. I wonder how he gets to work, anyway?

ONE NIGHT ONLY! The T will provide 24 hour service this Saturday

It’s kind of gimmicky, but this Saturday, the good ol’ MBTA will be pretty darned close providing 24 hour service on some routes. The reason? Well, to start, late night schedules, but mostly because it’s the beginning of daylight savings time. Here’s the alert from the T:

Saturday: Despite the start of Daylight Savings Time, the number of available Late Night trips will remain the same Sunday morning (March 8). Last trains will depart from downtown at 3:30 a.m. with outer connections following later.

At 2 a.m. on Saturday, the clocks will magically advance to 3 a.m. The MBTA services running will not magically disappear in to the ether, but the T will basically assume that the time change won’t take place until the end of service. So some of the latest-running trains and buses, which normally don’t finish their runs until about 3:00, will actually not reach their terminals until 4:00. Notably, the last 28 bus will reach Mattapan at 4:05 a.m., the last Mattapan trolley will arrive around the same time, and several other lines will operate until about then.

Most T service doesn’t begin until 6 a.m. on Sunday mornings, but a couple of lines, notably the aforementioned 28, operate early airport service. (There should be a discussion that better service should be provided to the airport, which has expensive and limited parking, many low-wage jobs, and many early shifts, and which is completely inaccessible from most of the city by walking or bicycling, because ocean.) So service at Mattapan this Saturday will include:

3:00: inbound 28 bus departs *
3:15: outbound 28 bus arrives
3:20: inbound 28 bus departs ‡
3:40: outbound 28 bus arrives
3:45: inbound 28 bus departs *
3:59: inbound 28 bus departs †
4:05: outbound 28 bus arrives
4:45: inbound 28 bus departs †

* Saturday late night service   † Sunday AM service   ‡ Trip scheduled on both Saturday late night service and sunday AM service (!)

Now, it’s worth noting that there is a service gap of nearly three hours in outbound service: the first outbound bus on Sunday isn’t scheduled to arrive in Mattapan until 6:40. But what I find most intriguing is the fact that for nearly an hour, the Saturday and Sunday service actually overlaps (on a normal weekend, the last outbound arrival comes in just 15 minutes before the first inbound departure). Most interesting: the 3:20 a.m. inbound trip can be found on both the Saturday schedule (the 2:20 inbound trip bumped an hour) and the Sunday schedule (the regular 3:20 departure). Will the T run two buses inbound from Mattapan simultaneously, one on a Saturday schedule and one on a Sunday? It’s almost worth venturing down to Mattapan to see.

These are strange times we live in indeed.

Don’t use bus routes to subsidize malls …

especially if the mall isn’t the final stop on the route.

I recently had the pleasure of riding the entire route of the 34E, one of the MBTA’s longest bus routes. The route starts in Walpole Center, makes a beeline to Washington Street (which extends from Boston to Providence) and runs in a straight line to Forest Hill Station. A straight line, that is, except, for a bizarre figure-eight loop through the Dedham Mall. The loop-the-loop to access the mall unnecessarily lengthens the route, costs the T money, costs passengers time, and subsidizes private development, all to service the front door of an auto-centered development.

Instead of continuing on Washington Street, the mall loop takes 8 or 10 minutes as the bus leaves the street, navigates no fewer than eight stop signs and traffic signals, makes two separate looped turn-arounds and traverses the same intersection three times. The route is scheduled for a full hour for the 14 mile trip from Walpole to Forest Hills, so the detour through the mall accounts for 13 to 16% of the total run time, all to serve two stops (out of more than 80 total on the route) which would otherwise require a 2 to 5 minute walk.

In other words, for riders wishing to get to the Dedham Mall, it would likely be faster if the bus ran straight on Washington Street and they got off and walked in to the mall, rather than taking a circuitous route to be dropped near the door. And for everyone else, it would save 8 to 10 minutes each way of not riding through the mall parking lot.

I rode the route on a weekday evening a few days before Christmas. This should have been a high water mark for people using the 34E to get to the mall. While my bus was full—there were probably between 45 and 50 passengers on board at any given time (and probably 70 or more served along the route)—only two or three got on or off at the mall. So, in order to serve this small number of passengers, the rest of the bus had to loop in and out and in and out of endless parking lots and driveways, because front-door service to the mall is apparently required.

From HumanTransit.org

What is particularly irksome is that in this case—and it’s not isolated, but, at least in Boston, perhaps the most egregious (the 350 serves the Burlington Mall with a similar detour, but much closer to the terminus of the route, meaning that many fewer passengers are inconvenienced by the route’s detour)—is that anyone who rides the bus past the mall has their trip dramatically lengthened (how dramatically? 18 minutes a day, five days a week, 50 weeks a year adds up to 75 hours of extra time on the bus annually). Jarrett Walker talks of “being on the way” and the mall is decidedly not; the 34E takes what should be a straight-line transit trip and degrades it to a mall circulator, despite the thousands of passengers who ride the bus daily.

In addition, running service via the mall requires several hidden subsidies which degrade service and provide a perverse incentive for people to drive instead of use transit. This one, in turn, further subsidizes the car-centric mall over pedestrian-oriented business districts, several of which are served by this route. There is also the direct subsidy to businesses at the mall. If I open a store on a street near an existing transit line, I would not (and should not) expect the transit agency to reroute the transit line to provide a stop at my front door. Yet we provide this service to the mall.

This subsidy can be quantified, in fact. The T doesn’t break down service between the 34E and the 34, but let’s assume that slightly more than half the passengers on the route are carried by the 34E (looking at the total number of vehicles on the route at different times of day)—or about 2500 passengers. The route costs $3.09 per passenger to operate (66¢ average bus fare paid plus $2.43 subsidy), or a total cost per day of about $7725. If we calculate 15% of this approximately $1150, meaning that over the course of a year—even given lower service levels on weekends—the cost to serve the mall is well north of $300,000 per year. [Update: these numbers may be somewhat lower given that morning service—before the mall opens—and some peak evening rush hour trips do skip the mall.]

Here’s another way to look at this: currently, the 20 minute evening headways on the 34E requires 6 buses running the route in about (or just under), each bus makes a round trip in two hours. If the run time were reduced to 51 minutes by omitting the mall, the same six buses could make seven round trips, reducing headways and, thus increasing capacity on the route. If you could get it to 50 minutes, the same headways could be maintained with 5 buses, which would save 1/6 of the route’s operating cost while providing the same service. But, instead, we provide service to the mall, at the expense of everyone who isn’t the mall.

What to do? Make the mall subsidize the route—yes, to the tune of $350,000 per year—or have them build an ADA facility from Washington Street to the mall. The extra cost of running this route in to the mall for 10 years could buy a very nice set of bus shelters, crosswalks and a ramp from Washington Street to the mall’s front door. Another option would be to run the 34—which ends its route nearby—to the mall, instead of putting this joggle in the middle of the 34E. While it might not have the same cost savings, it would at least not have the effect of costing thousands of passenger hours each day. Or, abandon service to the mall all together. Malls are dying, anyway, and it should not be the business of public transit agencies to help prop them up.

The 70 bus is just … bizarre

The Boston Globe carried a story this week about Watertownies (Watertownians?) who want better MBTA bus service. Watertown is one of the furthest-in, densest communities in the Boston area with only bus service, and residents want improvements. Residents of Watertown are asking for more buses at peak hours (the T doesn’t have the vehicles to provide this), faster service (perhaps they should invest in bus lanes) and better services overall.

There is particular sentiment about improvements along the Arsenal Street corridor, which is served by the 70 bus. And the 70 bus is one of the most interesting routes in the MBTA system, and one which could certainly stand to be improved. In fact, it’s bizarre, a compilation of several separate routes, and it seems to have taken place haphazardly. The route is one of the longest in the system, and its headways are such that while it may operate on average every 15 minutes, there are frequently much longer wait times, leading to crowding, bunching and poor service levels.

The T claims to want to study the route, but can’t come up with the $75,000 to do so. We here at the Amateur Planner will provide a base analysis (for free), in hopes that it can be used to improve service on this route. One concern in the article is that “There are people waiting 40 minutes for a bus that’s supposed to run every 15 minutes.” Unfortunately, this is not an isolated occurrence based on equipment failures and traffic, but rather the fact that the 70 bus route is set up with uneven headways which mean that a bus which is supposed to come every fifteen minutes might actually have schedule gaps much longer. It’s a complicated story, but fixing the 70 bus should be a top priority for the MBTA.

I. The Route

The 70 bus was, like most bus lines in Boston, originally a streetcar line, much like the 71 and 73, which still run under the wires in Watertown. When the 70 was converted from streetcar to trackless in 1950 and from trackless to diesel ten years later, it was much like any other MTA route. It ran along an arterial roadway from an outlying town center (Watertown) to a subway station (Central), a similar distance as, say, the 71 or 57 (a car line until 1969) intersecting it in Watertown Square. But after that point, it’s fate diverged. Most other lines continued to follow the same routes they always had. The 70, however, absorbed services of the Middlesex and Boston, leading to a much longer route. As time went on it was extended to Waltham (in 1972, combining it with the M&B Waltham-Watertown line) and then to Cedarwood. The 70A routing was only merged in to the route in the late 1980s when through Waltham–Lexington service was cut, adding a third separate line to the 70/70A hodgepodge. (More on the history of this—and every other MBTA route—here.)

It now extends—depending on the terminus—10 to 14 miles from Central Square in Cambridge to nearly the Weston town line. Along the way it serves several distinct activity nodes: Central Square in Cambridge, Barry’s Corner and Western Avenue in Allston, the Arsenal Mall, Watertown Square, Central Square in Waltham, and the outlying branches. While these nodes fall in a straight line, it creates a bus route with several loading and unloading points and heavy use throughout the day. This is not a bad thing—except that the line is poorly scheduled and dispatched, so that it effectively provides far less service than it could.

II. The Schedule


To its credit, the MBTA has very few split-terminus routes. (In many cities, split-terminal routing is the norm, as one trunk route will branch out to several destinations. Since MBTA buses generally serve as feeders to rapid transit stations, it is far less prevalent.) The 34 has short-turn service (the 34E) and the 57 has some short-turns as well. A few other routes have some variations (the 111, for example) but few have the sort of service that the 70/70A has. The 70A is particularly confusing inasmuch as the morning and afternoon routes run separate directions, to better serve commuters but to the detriment of providing an easy to understand schedule. It it almost as if the T has put all of its annoying routing eggs in one basket. Or, in this case, in one route.

The issue is that while there are two routes which are generally separately scheduled, for the bulk of the route, from Waltham to Cambridge, the operate interchangeably as one. For someone going from Waltham to Cambridge or anywhere in between, there should be no difference between a 70 and 70A. If there are four buses per hour, there should be one every fifteen minutes. For those visiting the outside of the route, the buses will be less frequent, but for the majority of the passengers, it wouldn’t matter.

Except, the route doesn’t work this way.

It seems that the 70 and 70A are two different routes superimposed on each other with little coordination. This often manifests itself in buses that depart Waltham—and therefore Watertown—at nearly the same time, followed by a gap with no buses. If you look at nearly any bus route in Boston, it will have even (or close-to-even) frequencies during rush hours. Some—the 47, for instance—may have a certain period of time with higher frequencies to meet demand. But even then, the route quickly reverts to even headways.

This is not the case with the 70 bus. If you are in Watertown Square traveling to Cambridge on the 70, there are 16 buses between 7 and 10 a.m. This should provide service every 10 to 12 minutes. Here are the actual headways (the 70As are bolded):

16  7  9  9  6  13  8  12  8  24  0  24  5  15

Anyone want to point out the problem here? The headways are completely uneven. The route is frequent enough that it should be a “just go out and wait for the bus” but it is completely hamstrung by poor scheduling. The initial 16 minute headway will carry a heavy load—nearly twice the headway of the next trip. The next trip will operate with half the load, and more quickly, catching up on the heavily-laden bus ahead of it. Later in the morning it gets worse: headways inexplicably triple from 8 minutes to 24, followed by two buses scheduled to leave Watertown at exactly the same time. (In fact, one is scheduled to overtake the other between Waltham and Watertown.) This is followed by another long service gap. Miss the two back-to-back buses, and you’re waiting nearly half an hour. This makes no sense.

And it’s not just the mornings. Midday headways are just as bizarre. When traffic is at a minimum and the route should be able to operate on schedule, headways range from 10 to 25 minutes. There are at least three buses each hour (and usually four) yet there are long service gaps—the effective headway is nearly half an hour when it could conceivably be 15 minutes. It’s obviously not easy to schedule a route with two termini, but the vagaries of the schedule mean that missing a bus may mean a wait of nearly half an hour, only to have two buses come with ten minutes of each other. And it’s not like these buses are empty, either. They serve the bustling town centers in Waltham and Watertown, and the Arsenal mall area stops regularly see ten or more passengers per trip. Yet they are subjected to a bus that comes at odd times—not one that is really reliable.

For a time during the evening rush hour, the T actually manages to dispatch an outbound bus every 10 minutes. But overall, most of the weekday schedule is a range of times which have no relation to each other, and mean that the route provides a much lower level of service than it could. (Intriguingly, Saturday service on the 70 is provided on an even 10 minute headway for much of the day; it’s a shame this schedule can’t be used on weekdays, too.)

I’ve been experimenting recently with graphically displaying route schedules. It shows scheduled route times as points, and headways as lines. Time of day is on the x axis, frequency and running time on the y axis. Here, for example, is the 47 bus:

Notice that while there is a major service increase during the AM rush hour, the headway lines are generally flat during different service periods during the day.

Another example is the 77 from Harvard to Arlington:

The 77 is a very frequent bus which sees 8 to 12 minute headways throughout the day. There is some minor variation at rush hours—and longer scheduled trip times at those times—but variations are minimal, and when headways change, they do so by only a couple of minutes.

Most bus routes have this sort of chart. Trip times may vary, but headways do not change drastically during the day.

Now, here’s the 70 from Waltham to Boston:

This is chaos! Instead of a flat line, the headways bounce around uncontrollably, ranging from one or two minutes (this is from Waltham, so the 0 minute headway in Watertown Square is slightly different) up to nearly half an hour. If you go wait for a bus you may see two roll by in the span of five minutes, and then wind up waiting 25 minutes for the next. It’s only during the evening rush hour (the flat blue line) that there is any order to the schedule; even late at night headways bounce around by five minutes or more.

Another way to visualize these data are to look at the average headway versus the effective headway. Here, the gray line shows the moving average of three headways, which smooths out some (but not all) of the variability shown above. However, the yellow line is more important: it shows the greatest of the three headways, which is the effective headway: if you go out and wait for a bus, it’s the maximum amount of time you may wind up waiting. Here’s the inbound route:

The average headway for bus is generally about 10 minutes at rush hours, and 15 to 20 minutes during the midday, which is not unreasonable for this type of route. However the effective headway is much worse. It is more than 20 minutes for much of the day—and often eclipses 25 minutes. For most routes, the average and effective headway would be equal (or close to it). For the 70, the effective headway is sometimes double the average.

The outbound chart shows what is possible. From 4:00 to 6:00 in the afternoon, the average and effective route are nearly even—this is when buses are sent out on equal headways (and this is what the entire day would look like for most routes). However, during much of the rest of the day, the headways are less sensible. It should be possible to operate a service every 20 minutes or better, but there are often 25 minute waits for the bus, despite the fact that the two routes share an outbound departure point in Central Square.

All of this does not align with the T’s stated policy. According to the MBTA service deliver policy, “passengers using high-frequency services are generally more interested in regular, even headways.” This is the practice for most routes, but not for the 70.

III. What can be done?


As currently configured, the 70’s headways are particularly hamstrung by the 70A. Not only is it longer and less frequent than the Cedarwood route, but it’s outer terminus is not even a terminus but instead a loop (with a short layover), so the route is practically a single 25-mile-long monstrosity beginning and ending in Central Square. Without a long layover and recovery point, the route is assigned two buses midday and can’t even quite make 60 minute headways: the 10:10 departure from Cambridge doesn’t arrive back until 12:11, and that’s at a time of day with relatively little traffic!

It’s also not clear why the 70A needs to run to Cambridge. It is a compendium of three routes—the original Central–Watertown car route, the Middlesex and Boston’s Watertown–Waltham route and the Waltham portion of the M&B’s Waltham–Lexington route. This is a legacy of the 1970s—and before. It would seem to make much more sense to combine the 70A portion of the route with one of the express bus routes to downtown Boston, and run the 70 as it’s own route with even headways.

There seem to be two reasonable routes to combine the 70A with, each of which could probably provide better service with the same number of vehicles: the 556 and the 505. The 556 provides service from Waltham Highlands (just beyond the Square) to Downtown Boston at rush hours, and to Newton Corner at other times. It has an almost-identical span of service to the 70A and operates on similar headways (30 minutes at rush hours, 60 minutes midday). Instead of running all the way in to Cambridge, 70A buses could make a slight diversion to serve Waltham Highlands and then run inbound to downtown. Currently, the 70A is assigned five buses at rush hour, and the 556 four. It seems that using two of these buses to extend the 556 to North Waltham would easily accommodate 30 minute headways, freeing up three buses to supplement service on the 70. During the midday, one bus could provide an extended 556 service between North Waltham and Newton Corner (where connections are available downtown), and it might be possible to extend run 60 minute headways between downtown and North Waltham with just two buses, allowing the other to supplement service on the 70, or allow for transfers to the 70 and Commuter Rail in Waltham and express buses in Newton Corner.

The other option would be to extend the 505. The 505 is currently a rush hour-only bus, but its span of service matches that of the 70A at either end, it is only from 10 until 3 that it provides no service. The simplicity with the 505 is that it’s current terminus is in Waltham Square, so it would be a simple extension to append the 70A portion to the route. The 505 currently runs very frequently in the morning with 10 buses providing service every 8 to 9 minutes, and has 7 buses running every 15 minutes in the evening. If every third bus in the morning and every other bus in the evening were extended to North Waltham, it would provide the same level of service as the 70A, but with direct service downtown. Midday service would be more problematic, as it would require two buses to operate, and additional vehicles would be necessary to supplement the loss in service on the 70 (although the T has a surplus of buses midday, so while it would require extra service time, it would not incur new equipment needs).

Either of these solutions would allow for 10 vehicles to provide service on the 70 route at rush hour, and they could be dispatched at even intervals during that time. With recovery time, the roundtrip for the 70 at rush hour is less than 120 minutes, so with ten buses it could easily provide service every 12 minutes, and perhaps be squeezed down to every 10 minutes with faster running time on the shoulders of rush hour. If every other trip was short-turned at Waltham, 10 minute service would be possible, with service every 20 minutes to Cedarwood. And the headways would be even—no more 20 minute waits in the middle of rush hour. Transfers could be made at Waltham for 70A patrons wishing to go to Watertown or Cambridge. During the midday, similar even headways of 15 or 20 minutes could be offered—no more long waits for a crowded bus with an empty one right behind.

Over the years the 70/70A has been cobbled together from a number of routes, and this has hobbled the efficacy of the route. While the exact scheduling of the route has to take in to account many other factors (pull outs and pull ins, union rules, break times, terminal locations and the like—and as someone who recently helped create a route plan for a very short route, I can attest there is more to route planning than meets the eye), it would be hard to make it any worse than it is now. With some creative thinking, the T should be able to provide better service for everyone who takes the 70 bus without expending any more resources, and should be able to increase the effective capacity, and make it a better experience for its customers.