Friday, February 20, 2015

Snow daze

Spotted this while passing through -- first snow of the year and it's still fun for bicicle snow man
Blizzard returns streets to people
Best way of getting around now
No revenue service, but trains clearing snow still need a second operator apparently!
A space taken by automobiles returned to the people for one day.

Headed for the hills
Second best way of getting around in the snow (after skiing)

Such a strong desire line @ Naples Rd that people climb mounds of snow to use it
Snow soccer in what is regularly a dangerous intersection
Walking is the dominant mode of transportation on Comm Ave
Even on the deteriorating highway overpass, with tiny sidewalks
Guess who the city doesn't care about!
I could not navigate this canyon
Not a flake on the ground for drivers, however!
The bus stop is starting to disappear beneath the mounds of snow
Beautiful nearly dry pavement for motorists -- slush for people walking.
Cambridge Street overpass of I-90 is even less friendly in a blizzard
Sidewalk's gone
All that remains of the Framingham line
That Kenmore Square crosswalk STILL hasn't been cleared out
Park your car on the sidewalk and avoid shoveling snow! City says: "No violation found" either.
Relics of civilization pasT
Ah screw it
The Green Line is canceled and now what?
Snow tracks
Free (illegal) parking deemed more important than transit
Let's build a mountain of snow on the tracks!
The mountain is moving faster than the Green Line: faster than zero
The 57 cannot handle the load even late at night
Naples Rd desire line strong as ever, no matter what
They're waiting for the shuttle bus that may never come

Tuesday, January 20, 2015

False pretexts: motorists only pretend to care about ambulances when doing so happens to be convenient

Two bits of news hit recently that may seem unrelated, at first: Lawmakers seek crackdown on highway protests:
Rep. Colleen Garry, a Democrat from Dracut, proposed making it a felony to block highways. She told the Lowell Sun she was furious about the Thursday morning protests that blocked two sections of the heavily traveled highway through Boston, one north of the city and one south.
"I'm just outraged that people would be that reckless," Garry said. "Everyone has a right to protest, but to do that kind of thing in a highway or a roadway?" [...]
Nearly 30 protesters were arrested and arraigned on charges including trespassing, disorderly conduct, resisting arrest and willfully obstructing an emergency vehicle.

State police said an ambulance transporting a seriously injured car crash victim to a Boston hospital was forced to divert to a hospital outside the city that did not have a trauma unit. The man survived.
State Sen. Richard Ross, a Wrentham Republican, filed legislation that would impose a minimum $5,000 fine and allow a jail sentence of up to six months for willfully trespassing on state highways. Current law allows for a maximum $50 fine and a jail term of no more than three months.
And the same week, State to propose opening S. Boston Bypass Road to all drivers:
State transportation officials will file a notice in February with Massachusetts environmental regulators to allow cars coming into South Boston to use the Bypass Road, which is currently restricted to trucks and other commercial vehicles. The pilot program would last six months and could begin as soon as March. [...] 
The 1.1-mile road was built to accommodate trucks during the construction of the Central Artery, and when the tunnels were done, the road remained restricted. But as traffic becomes heavier in the fast-growing Seaport District, there has been pressure to open up the road to everyone. [...]
As part of its filing, the state will also propose letting all drivers use the high-occupancy vehicle lanes outside of South Station and the South End.
These two pieces of news are, in fact, related: because together they illustrate the hypocrisy and insincerity of our Commonwealth's transportation policy with regard to emergency vehicles. If our elected officials truly cared about emergency vehicle response time -- which they should -- then they would put a quick end to this proposal that will destroy the efficacy of both the South Boston Bypass Road as well as the HOV lanes outside of the South End. If not, then it is quite clear that these politicians, Rick Ross and Colleen Garry, are merely posturing and mouthing platitudes, all while silently sticking it to emergency responders. By far the most common obstacle for emergency vehicles on our roads is not protesters: on a daily basis, emergency vehicles are obstructed by other motorists and the traffic jams created by motor vehicles.

First, a little background: it is quite common for ordinary motorists to believe that the exact same facilities that enable their own travel at high speeds are also beneficial to emergency vehicles. A related objection to certain traffic-calming measures is that they will slow emergency response. However, in reality, the truth is much more complex and requires context-specific analysis. More car capacity might help emergency vehicle response time, under some circumstances. In other scenarios, additional car capacity might harm emergency vehicle response time. An additional, open, free-flowing lane can help emergency vehicles -- but if that same lane jams up with private automobiles then that lane just becomes an obstacle: an overall detriment to response times. In that scenario, removal of a jammed travel lane -- a reduction in car capacity -- can give emergency vehicles the maneuvering room they need in order to avoid the obstacle created by other motorists.

BU Bridge under renovation (source)
The BU Bridge renovation project gives a prime example of how removal of a lane can help emergency vehicles. The engineers behind this project understood that the prior existing condition of having four substandard travel lanes (with no shoulders) was unsafe and liable to create immovable jams at a crucial choke-point for emergency vehicles traveling between Boston and Cambridge. Therefore, they chose to eliminate a lane and reallocated its space into a pair of 5-foot shoulders on either side of the motorway. These shoulders are not intended for motor vehicle travel but they do provide a space for other vehicles to pull over while yielding to an emergency vehicle. In addition, they provide breakdown space to help recover from crashes or other incidents. They also serve as a continuation of the bike lanes coming from Boston. All-in-all, a fairly solid engineering compromise, considering that the intersections on both sides of the river need substantial renovation and rethinking.

But none of those safety issues were important to motorists such as Stanley Spiegel, who was quoted in the Boston Globe, in February of 2009, making this threat:
"There's going to be road rage," predicted Stanley Spiegel, who lives across the bridge in Brookline. "If you're going to spend public money to go for an improvement, you don't predictably make things worse.
This kind of attitude shows zero concern for the safety of anyone else, but it is sadly all too common among entitled motorists of Mr. Spiegel's ilk. Whenever safety or emergency response goals conflict with increased car capacity, we can see quite clearly where motorists like him stand. Thankfully, in the case of the BU Bridge thus far, MassDOT has not capitulated to the bullies who would remove the shoulder space and turn it back into a fourth congested travel lane.

The South Boston Bypass Road (source)
The South Boston Bypass Road was assembled out of a narrow right-of-way for the purpose of helping the industries along the waterfront thrive during the Big Dig. It also keeps a bunch of heavy trucks off of the regular city streets, and it provides a clear lane of travel for emergency vehicles operating between the South Boston Waterfront and South Bay. As you can see from this picture, the shoulders are fairly small: they seem to vary from 2-4 feet. It's not a road designed for high volumes of traveling vehicles. As a result, heavy traffic induced on this road could result in jam-ups that would be impassable for emergency vehicles.

For a number of years, pundits such as Shirley Leung have been campaigning to allow private cars on it. She has quoted old-school 'highwaymen', such as Frank DePaola (who coincidentally is the interim Secretary of Transportation right now), with statements like this: "If you have traffic, and you want to relieve it, you have to find road capacity." As a result of this kind of short-sighted thinking, the South Boston Bypass Road will be jammed up with private cars and will not be able to serve its former purposes any longer. And it goes to show, that when the political push comes to shove, concerns about emergency vehicles suddenly disappear, in favor of a temporary band-aid covering up much deeper, systemic problems with South Boston transportation.

HOV lanes are also a popular target of attack by privileged motorists. It's so common that it's even got a name: the "Empty Lanes Attack", so called because drivers will often claim that the HOV lanes are "mostly empty" or not being used, and therefore should be given over to single-occupancy vehicles. What they (intentionally) fail to realize is that the relative emptiness is what gives the HOV lane its value: it is passable. If it were congested, then it would not be useful. Too bad, then, that even our Boston MPO doesn't seem to understand that most basic of concepts. And because such lanes are designed not to be congested, they are also useful for emergency vehicles that need to bypass major traffic congestion. Thus, the proposal to 'open' the HOV lanes outside of South Station to general traffic will result in degradation of emergency response times.

Where is the outrage? Why, of course there is none: because motorists only pretend to care about ambulances when doing so happens to be convenient. The "Empty Lanes Attack" trumps their false concern about emergency vehicles: the allure of additional single-occupancy vehicle road capacity takes precedence over safety principles.

If officials really cared about emergency response times, then I-93 would have full-width shoulders and/or HOV facilities/zipper lanes extended all the way from end-to-end: taking existing lane space where necessary. It's the only responsible way. But, in fact, the current configuration of the highway that excludes such safety features from much of its length, especially where most constrained. This shows where the true priorities lie: always pushing for 8 lanes of general travel no matter what the consequences are to emergency vehicles or highway safety. Convenience for drivers of single-occupancy vehicles is more important than safety, to our decision-makers.

The fact is that it's easy for officials to claim that they care about emergency vehicle response times when doing so also means more capacity for drivers. But real courage would be shown by officials who show that they care about emergency response even when it's not politically convenient to do so. That means support for restricted lanes such as HOV or bus lanes. That means supporting safety features within the existing right-of-way of roads, without requiring costly expansion. And that means not playing these insincere political games in which 'concern' for safety only arises when it is useful for pursuing another agenda; when that same 'concern' suddenly vanishes the moment it is no longer useful.

Sunday, January 11, 2015

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.

Wednesday, December 17, 2014

Stupid idea of the month: pretending to solve pedestrian signal timing issues using Pong

 Game lets you play Pong with a person on other side of the crosswalk (source)
ThisIsColossal reports on "ActiWait", which is a video game with controllers on either side of a crosswalk, allowing two waiting pedestrians to play a game of Pong.
The ActiWait is a new generation of traffic light buttons. Installed at a pedestrian traffic light with long red phases, it offers pedestrians the possibility to convert boring waiting times into positive experiences. Through a touch screen which is installed in the upper shell of the button, people can interact with each other across the street.
As a public art project, it's neat. Especially while it retains novelty value. But as a "solution" to long red phases, it's incredibly stupid and condescending. Let's get this straight: is it okay to subject pedestrians to needlessly long wait times at traffic signals, so long as you give them a 1970s video game to play? Absurd. What's the message being sent here? As near as I can tell, the message is: "You walked? Well then, your time is worth less than that of a driver. Here, play a game, instead of getting where you're trying to go."

The solution to long waiting times is not games... the solution is shorter waiting times. Engineers should respect the fact that pedestrians are people too and they don't appreciate being forced to wait excessively long times simply for the convenience of motor vehicle drivers. This is not a difficult topic, and it demands no techno-wiz solution. The answer is simple: shorten traffic signal cycle times to reduce average waiting times. And don't require the use of "beg buttons" to cross the street. Pedestrians should be given at least as much respect as drivers. If you don't make drivers press buttons or play games at traffic lights, then you shouldn't force pedestrians do that either.

Slides from Ricardo Olea, SF MTA (source)
San Francisco is known for its pedestrian-friendly signal timing. As you can see, engineers at SF MTA understand that overall cycle length is very important to the pedestrian experience.

Doubling the cycle length causes the average delay for pedestrians to more than double. In San Francisco, a 60 second cycle length is fairly standard. Unfortunately, in Boston, most signal cycle lengths are between 90 and 120 seconds. Sometimes they vary depending upon time of day -- usually lengthening during rush hour. 110 seconds is a fairly common cycle length, in my experience. All of this is firmly in the "red" according to SF MTA, leading to unhappy pedestrians. Well, actually what happens is that Bostonians quickly learn to ignore the signals because the timing is quite obviously terrible.

ActiWait is from Germany so hopefully they will stay over there. Or perhaps they can invent a game that convinces traffic engineers to treat pedestrians better. Here's an idea: perhaps a little device that can be installed in their cars. At every single signaled intersection, it forces them to stop, push a button, and wait 50 seconds on average for a green light. The fun part is that if you push the button at the wrong time during the cycle, you may have to wait an extra cycle to go around before you get a chance to proceed. That's how signals in Boston are programmed. All the fun of a slot machine, and none of the reward!

Saturday, December 13, 2014

The SPOT app undermines the Clean Air Act, and therefore our air quality, in Boston

I recently read about the "SPOT app" that allows people to easily rent out an empty parking spot that they own and are not using. Sounds reasonable enough. I'm a fan of making more efficient use of physical resources. It's the opposite of "minimum parking quotas" that force everyone to waste huge amounts of land and money, and yet still fail to meet parking demands.

"SPOT app" (source: BostInno)

But, when I took a look at the map included with the article, it occurred to me that there is something not quite right about this. The app allows you to rent spaces in the Back Bay and downtown Boston. It transforms so-called "accessory spaces" that are attached to particular uses (such as residences) and allows them to be used instead as "commercial spaces" that are available to anyone, for a price.

So what's the big deal?

Well, back in the 1970s, the city of Boston was facing an air pollution problem caused by the creation of all those urban highways that tore through the city, bringing hundreds of thousands of cars spewing exhaust fumes into the air. In order to satisfy provisions of the Clean Air Act, the city of Boston agreed to cap the number of "commercial spaces" that would be available at any one time. It's called the "parking freeze" and it's intended to help preserve our air quality. The downtown Boston parking freeze cap is currently set at 35,556 spaces, and there is no capacity for new spaces at the moment. Yet, the SPOT app is effectively creating new commercial spaces that have not been subject to the parking freeze regulations. That means more cars, more air pollution, and more congestion.

I think it would be appropriate if the company that created the SPOT app were to be proactive about dealing with this air pollution problem. Perhaps they should disable the use of the app within the parking freeze zone until they figure out a way to mitigate the air pollution caused by the additional cars they may be attracting into downtown Boston. Perhaps it should only be available for electric vehicles within that zone. Or perhaps they need an allocation from the freeze "bank" in order to offer spaces in that zone. I don't know what the best solution is. But I do know that it is something that should be addressed. 

I'm also a little disappointed that City Councilor Frank Baker did not consider the implications for the parking freeze, the Clean Air Act, and our air quality, before providing an endorsement of the app.

One thing I did find really interesting is that the company behind this app has been collecting price information about short-term parking in various parts of Boston. This article has a breakdown. Average prices range from $1.75/hour in Allston/Brighton up to $3.75/hour in Back Bay. What's remarkable about these averages is that (a) they're higher than the city-wide set meter price of $1.25/hour, and (b) they're really not that expensive, and quite reasonable when compared with typical meter prices in other American cities. Even the Back Bay's average market-driven price of $3.75/hour is less than meter prices in busy parts of Vancouver, New York, Chicago, Los Angeles, and Seattle. Does it really make sense for places like the Back Bay and the South End to have city meter rates that are comparable to Boulder, CO or Rochester, NY (both $1.25/hour)? Hopefully, this inspires the city to give another look at using smart parking reform to address parking issues, instead of hurting the residents of the city with onerous minimum parking quotas. Those quotas are especially harsh on people who don't even own automobiles and yet are still forced to pay the cost to park other people's cars.

Monday, December 1, 2014

Thoughts on Question 1 and transportation funding in general

It's been a few weeks since the November elections, so I'm chiming in a bit late, but there's no real hurry. There weren't really any surprises with the state-wide office elections, and I don't know how that will all shake out in the new year when the new officials take office. But the success of Question 1 was a bit of a surprise to me. Part of that is the almost complete unreliability of polling on such questions. But also because Question 1 was so obviously a "Tea Party temper tantrum" that I figured Massachusetts voters would see through it.

In the past year, the legislature had finally taken some responsibility for transportation funding -- after twenty years of denial. They raised the gasoline excise tax by 3 cents, not enough to make up for the value lost through inflation, but something. And more importantly, they arranged an "indexing mechanism" that would ensure that we would not suffer through another twenty year period of fiscal farce. The "indexing mechanism" would keep the value of the excise tax steady over the years, ensuring that the regular effect of inflation would not become a source of de facto tax cuts.

Question 1 repealed the "indexing mechanism", thereby spurning the fiscally responsible step taken by the state legislature. Therefore, the gasoline tax will, in effect, receive an automatic tax cut every year going forward, again. Voters here have rejected irresponsible tax cuts in the past, so it's a bit of a head-scratcher, but hopefully not a trend-setter. In any case, if you are ever in conversation with a voter who claims to be "fiscally responsible" ask them if they voted for Question 1: if so, you can safely call them a hypocrite.

So what happens now? Well, the legislature is going to have to scramble a bit to find funding for some things. There are still plenty of failing bridges, potholes aren't going away, the T has 45-year-old subway cars that can't go without replacement, and buses have to be replaced on a regular schedule. It appears that the latter two are not in danger, and neither is the important Green Line Extension project through Somerville. But funding for everything else is questionable. That includes part of the cost of the Allston Interchange project that will replace the failing riverfront viaduct of the Mass Pike and reshape the area, fixing many of the problems that the existing highway afflicts on the neighborhood. There's the River Street and Western Ave bridges, which are crumbling. And several hundred other overpass and bridge repair or replacement projects that I could scarcely begin to enumerate. Roads ain't free, despite the feverishly held beliefs of the mostly suburban, mostly automobile-dependent voters who forced Question 1 on us.

Meanwhile, MBTA bus and train fares are virtually guaranteed to go up by about 5% every two years. Somehow, once again, public transit riders have been left holding the short straw, while drivers continue to reap steadily increasing subsidies in the form of inflation-driven gas tax cuts. Funny how that always seems to happen.

Paul McMorrow has suggested that we should adopt the idea of regionally-based taxes to pay for transportation projects. Ballot questions enacting regional sales or payroll taxes are popular in many western states. But it's not constitutional in Massachusetts, so this would require some fancy footwork or a change. And there's a bigger problem: we will end up with a system where transit projects are funded via additional regional taxes, while highway builders get to keep helping themselves from the general fund. Not a good dynamic. If Boston is forced to tax itself just to keep the MBTA running, then why should Boston subsidize highways in central and western Massachusetts? Either all transportation projects should be considered regionally, or none at all -- because we're all in this together.

For a few ideas to consider, check out the report last month from the Urban Institute about how the various states are handling the gas tax. Some have indexed the price in various ways to the going wholesale price of gasoline, which is one way to simulate a percentage-based tax like sales taxes. Oregon and Virginia are piloting a major reform that replaces gas taxes with vehicle-miles-traveled taxes. This is thought to better represent the cost to society of operating a vehicle on the public ways. The Federal government has also floated the idea of allowing tolling to be used on interstate highways (where it was not grandfathered). Tolling would be a fair way to obtain funding for highways, the counterpart of paying a fare to ride a train or bus. Used properly, it would also have the benefit of actually reducing congestion: with automated electronic tolling it's hassle-free, and part of the proceeds can be used to fund really good public transportation for people who don't or can't drive.

Here's a reform package I've been thinking about:

  • Apply sales tax to gasoline. Right now, gas is exempt from the sales tax, which is a hugely regressive subsidy to drivers at the expense of lower-income families. If we were to instead apply the sales tax to gasoline, then the overall rate could be lowered, so that other goods and products that everyone buys would not be subsidizing gasoline (at least, not as much). This could be designed in such a way that any increase in cost for gasoline would be made up for by decreased cost in everything else.
  • Change the purpose of the gasoline excise tax: instead of funding transportation, an excise tax on gasoline should fund clean-up of the pollution caused by gasoline usage, and also public health efforts to mitigate the damage to human health caused by gasoline usage. The rate of the gas tax would be set at the level needed to achieve these public health goals, which include the Healthy Transportation Directive and the Mode Shift Goal.
  • Other excise taxes should go into the general fund.
  • Transportation should be funded out of the general fund based on the merits and cost-effectiveness of each project in question. Such projects should have to compete with other worthy projects in other departments, such as schools, housing assistance, health care, and yes, even tax cuts.
  • Ridiculously bad boondoggles such as South Coast Rail, which is expected to cost the state over $500,000 per projected rider, should be discarded until somebody finds a way to get the costs under control.
  • All congested highways should be outfitted with variable, automated, electronic tolling. The tolls would vary from free (when there is little demand) up to whatever amount is required to clear out congestion at that time of day. The precise formula would have to be carefully designed in order to avoid surprising people. The revenue from the tolls can be used in several ways, and there is a reasonable argument that some of it should be used to ease the regressive effect of the tolls. Part can go to boosting public transportation capacity and frequency along the corridor, making it a real, serious option for many more people. This has the nice side effect of bringing the benefit of the transportation infrastructure to the many people who cannot drive, for whatever reason. Another part can go towards income tax relief for the low-income users of the highway who still need to drive. The rest should go into the general fund.
  • End all parking subsidies. That includes the minimum parking quotas found poisoning most zoning codes. The authority to impose such quotas, which are an intrusion on private property rights, comes from enabling legislation in the General laws, so it should be possible to retract that authority at the state level. Minimum parking quotas waste land, destroy healthy environments, raise housing prices, and, in general, these kinds of subsidies help cause traffic congestion. It's hard to imagine a more self-destructive set of regulations.
Does this package have a chance of ever passing? I doubt it. There's too much powerful, vested interest in the status quo. As we saw with Question 1, people don't like it when you end their subsidies, even if they are really harmful, self-destructive subsidies that cost the rest of us dearly.

I'd be interested to hear other people's ideas about transportation funding reform.

Sunday, November 2, 2014

Induced demand is a real problem and it makes congestion relief nearly impossible

For some reason, contrarian articles on "induced demand" seem to be the topic du jour. While they are right to point out that induced demand is a more subtle and nuanced concept than the way it is sometimes popularly handled, both articles seem to err too far in the other direction. Induced demand is a real problem, even if some people sometimes misuse it when making arguments.

Reliability, frequency, and speed

I want to take a quick detour to talk about goals in transportation investment. People tend to make decisions about transportation based on many factors, which I will boil down into three: reliability, frequency, and speed. Reliability encompasses factors such as predictability of trip time, probability of vehicle breakdown, and in general, the ability to make a confident statement about your location at a future time. Frequency is a metric of opportunity: the number of chances that will you have to undertake your trip in the window of time that you have available. And speed is the cost of the trip in time. To be sure, there is some crossover: frequency affects average speed and predictability, for instance. But let's roll with this for now.

There are two major categories: scheduled transportation and unscheduled transportation. Scheduled transportation is largely mass transit, whether public or private. Unscheduled transportation includes modes such as walking, biking and most driving. Frequency is obviously a huge deal for transit; there is also a frequency limitation on unscheduled transportation caused by things like traffic signals, but it is usually small enough to go without notice.

For many people, reliability is the most important characteristic. Walking and biking tend to have the most reliability because they are the least complex modes. Transit with a dedicated right-of-way is also supposed to be highly reliable: a properly run railroad should operate like clockwork (the MBTA on the other hand...). Modes such as driving are very susceptible to being caught in unpredictable and chaotic traffic congestion because they are highly inefficient in terms of space. Cars are also complex pieces of machinery that can easily break down. And mixed-traffic transit gets the worst of it because it has to contend with traffic congestion as well as passenger loading.

Speed should be broken down into average and top speed. Walking is obviously the slowest in average and top speed. Biking does not have high top speed (for most people) but can often maintain decent average speed comparable to a local city bus or a slow train. Transit can vary depending upon quality of right-of-way and maintenance. Driving is usually the mode with highest top speed but in typical traffic conditions can have significantly slower average speeds; possibly even slower than transit or biking.

The speed and reliability of walking is almost always independent of the number of people walking, except in the extreme cases (important as they are). Biking is also mostly able to enjoy that same feature. Transit in a dedicated right-of-way has the capability of operating reliably independent of the number of people attempting to ride it -- up to a point. Once the number of people reaches a certain "crush" capacity then dwell times can be impacted if the operator takes no further action. Finally, driving and mixed-traffic transit are most clearly the modes that are bothered the most by other vehicles on the road. As a driver, or as a mixed-traffic transit rider, the reliability and speed of your trip is highly dependent upon the decisions made by thousands of other people.

Perception and reality don't always match. For example, many people perceive to be in "more control" when driving. But in fact, they're highly dependent on the behavior of other people. Another: many transit riders don't perceive slowness because they are absorbed in some other activity such as reading or working; whereas drivers traveling at the same average speed might be seething and pounding the steering wheel in frustration. And of course: "There is a very strong element of psychology behind traffic patterns."

So, when considering a transportation investment, there are multiple ways to increase capacity. But they do not all have the same effect, even when viewed in such an abstract fashion.

Induced demand

Halloween just passed, so let's talk about candy. Prior to Halloween, there is a high, and one might say inelastic, demand for candy. Many people want to buy candy for Halloween, almost no matter what. This usually shows up in stores as an increase in both supply and prices. Luckily for kids (and the young at heart), supply of candy is relatively easy to increase.

Post-Halloween, the demand drops off. People remember why they don't binge on candy, or let their kids do so, all year. Excess supply is sold off as prices drop in response to the lower, much more elastic, demand. Then the market returns to normal, at least, until the next spike in demand.

Normally, I don't eat much candy. I try to avoid too much sugar for health and personal reasons. And I don't want to spend money on something like that. I could easily go for weeks and months without having a piece of candy. But if you put a bowl of chocolates in front of me, I'll probably take one sooner or later. The low price and ready supply has literally induced my demand. But not every type of candy will have this effect. I'm mostly not a fan of hard candy and will probably just ignore it. And perhaps I've generated economic activity by consuming a piece of chocolate, but I may also be ruining my diet and harming my health.

You probably guessed where I'm going with this. One major difference between candy and transportation is that the supply of the latter is much, much harder to increase. With transportation, very large, very expensive fixed investments are usually expected to accommodate all fluctuations in demand over time. Furthermore, in the United States, people generally do not expect the nominal monetary cost of everyday transportation to vary based on supply and demand, even though prices regularly change for commodities such as candy, food and other items. Instead, the cost fluctuation of everyday transportation is usually expressed as traffic congestion or overcrowding.

When a transportation investment is made, it can both increase the supply and possibly lower the overall cost of travel (either perceived or real) in that corridor. And the way that travel patterns change is hard to predict, despite many efforts.

Former Bostonian, and now Los Angeles transportation blogger VamonosLA writes:
In a large city, there’s almost always going to be trips that people want to make but don’t because of large travel times. This is especially true in large US cities, where we underprice road capacity to the point that new lanes are almost always quickly filled. We misinterpret the construction of the new lane as having caused the demand, but it was there all along.
This is true but is only part of the story. To be sure, some trips generated do represent increased economic activity. Other trips might represent less efficient usage of the now-cheaper resource. For example, you might make multiple trips where one would have sufficed in the past. Or, it might be due to drivers who were enticed into giving up existing car-pools, or who ditched transit. They might even have switched from walking or biking in cases where the distances were feasible (perhaps not in LA).

For a rather stark example, suppose you live in a neighborhood with sidewalks and you are able to walk for many trips. Suddenly, the DOT decides to "improve transportation" by taking away your sidewalks and replacing them with additional car travel lanes. Most people would then choose to stop walking and start driving everywhere. Nowadays it seems unimaginable that such a thing would happen, but it has in the past, and continues to a lesser extreme: oftentimes it is not that sidewalks are removed entirely, but rather, walking is made more unpleasant for the benefit of motor vehicle traffic.

An unknown contributor to the Transportationist named JW writes:
I hate the term “Induced Demand”. I hate the idea that induced demand is something bad; something to be avoided. 
[...] From the individual’s point of view, access provides opportunities to more jobs, more entertainment and social options, and more alternatives for consumption of goods and services. From a business’ point of view, access provides a larger pool of labor and more raw materials. From a retailer’s point of view, access provides a larger pool of consumers. From a municipal government’s point of view, access allows more efficient provision of police protection, fire protection and ambulance service by reducing the number of facilities necessary for a given response time. 
[...] Transportation improvements that provide greater access per unit of time lower transaction costs. Lower transaction cost lead to great efficiency in the economy and a higher standard of living.
Although JW is careful to couch it in terms of access, which is a good thing, this otherwise sounds like an argument that could be lifted straight out of a 1950s highway builder's manual: new highways lead to greater efficiency and higher standard of living! According to this logic, the congestion on the new highway facilities justifies the construction of even more highways. Clearly something is broken in this reasoning.

The mistake that JW is making is that not all transportation improvements are equal, and that there are more considerations than just raw "access per unit of time", which itself is a difficult thing to measure in practice. For one thing, the increase in access by one mode (say, private car) can lead to the degradation in access by another mode (such as walking, or emergency vehicles). For another, some modes lead to far more pollution and other bad side effects like poor urban planning decisions (e.g. minimum parking requirements, urban renewal, pro-sprawl zoning laws, etc).

Congestion relief

But I think that by far the biggest confusion stemming from the debate around induced demand comes because people are often talking about different things. When highway builders are trying to sell expansion, and when the general public is getting excited about it, they often refer to "congestion relief" as the major feature of the proposal. But what is "congestion relief?" Is congestion relief equivalent to the fact that more people can travel more miles by car? Is congestion relief the possibly increased economic activity and higher standard of living that JW talks about? Is congestion relief the fulfillment of "latent demand" as described by VamonosLA?

I would argue that congestion relief is none of those things in the popular understanding of the term. Instead, congestion relief is generally understood to be an increase in reliability of travel and a subjective decrease in the frustration that each individual has when using the transportation facility. Highway builders sell highway expansion to a public that is hungry for predictable travel times and less stress behind the wheel. However, that sort of congestion relief is largely a false hope, precisely because of the phenomenon that has come to be known as induced demand. It doesn't matter whether that comes from latent demand, or even that it might represent increased economic activity: if the typical driver still experiences large variance in travel times, and high levels of stress, then the congestion relief was a mirage as far as he or she is concerned.

Even the level of spending associated with projects like the Big Dig did not make it immune from this effect. From the Globe:
A Globe analysis of state highway data documents what many motorists have come to realize since the new Central Artery tunnels were completed: While the Big Dig achieved its goal of freeing up highway traffic downtown, the bottlenecks were only pushed outward, as more drivers jockey for the limited space on the major commuting routes.

Ultimately, many motorists going to and from the suburbs at peak rush hours are spending more time stuck in traffic, not less. The phenomenon is a result of a surge in drivers crowding onto highways - an ironic byproduct of the Big Dig's success in clearing away downtown traffic jams.

[...] The findings also call into question the promises made when ground was broken in 1992. At the time, state officials said in a promotional mass mailing to the public that, when it was all done, "people will find the commute to their jobs faster and easier than ever."
The new tunnels may have been able to handle the flow coming into them, but those outer links themselves were not able to live up to the induced demand.


So what can be done about congestion, then? It has rightly been pointed out that transit improvement and biking facilities do not "reduce congestion" in this sense. Actually that point should be clarified further: those improvements do not "reduce congestion" when the travel demand is virtually inexhaustible. However, it is possible that in some cases demand is actually exhaustible: for example travel along Comm Ave in Allston, in which case those kinds of improvements can be very effective at real congestion relief. But for destinations such as downtown Boston, there will almost always be another driver willing to replace a trip that is mode-switched away from private vehicle.

All that does not make transit, walking and biking improvements worthless. Jarrett has discussed several reasons why transit is still very worthwhile even without "congestion reduction" and I won't reiterate, but I will add that dedicated-lane transit, walking and biking facilities all increase the supply of "reliable transportation" that boosts accessibility without the harmful side effects imposed by increased car travel. Walking and biking also have great implications for the health of urban neighborhoods and are worthwhile goals on their own.

The idea behind congestion relief is to try and make personal motor vehicles as reliable as walking, biking, or riding a well-run railroad. There are only two known ways to make that actually happen: (a) rigorous scheduling, or (b) decongestion pricing. Railroads avoid congestion and conflict by imposing very strict discipline and heavily analyzed schedules on the movement of trains. To try and apply that same discipline to private cars on roads is politically and practically unfeasible. Therefore that leaves decongestion pricing as the only known way to make private motor vehicle travel reliable, and it works by allowing the price of travel to vary based upon the supply and demand for travel. This is, of course, standard procedure for allocating just about every other resource in our society, but for some reason is completely ignored when it comes to roads. In any case, this article is about induced demand and I have already gone on too long, so I will leave discussion of pricing to others.

Friday, October 17, 2014

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.

Saturday, October 11, 2014

If you need a flashing sign then you failed at street design

In June, a speeding car spun out of control and killed two pedestrians walking on Beacon Street in the Back Bay. More recently, police arrested a man caught operating his Maserati at 100 mph on the same street. The city has responded by putting a sign on up Beacon Street near Clarendon:

Too little, too late

Charles Marohn has spent several years traveling the country, talking about the dangers of streets that are overbuilt for speed. Beacon Street is a prime example:

The sign says "30" and the street says "FAST".

Each of the three travel lanes on this street appear to be at least 11 feet in width, all going in the same direction. According to MGL Ch90 Sec17 the speed limit for a "thickly settled district" is 30 MPH. Yet, when looking at this wide open expanse of asphalt, is it any surprise that the speed limit is routinely flouted? A speed limit that is already set too highThe chance of a pedestrian being seriously injured or killed if struck by a car is 45% if the car is travelling at 30 mph but only 5% at 20 mph.

Jeff Speck has recently written an article calling upon all cities and towns to replace their 12- and 11-foot travel lanes with lanes no larger than 10 feet. This article is timely. Boston continues to design streets with 11 foot travel lanes, like Beacon Street, and the new design for Commonwealth Ave. This decision to build wide, highway-like lanes is a terrible mistake, with disastrous consequences for anyone not surrounded by two tons of steel. On Comm Ave, the city is actually planning on a 35 MPH design speed, even though the speed limit is 30 MPH, and the city itself recommends 25 MPH as a limit.

Boston has an unfounded belief in tiny, barely noticeable signs.
By designing and building such high-speed roadways, it's almost as if the city is encouraging drivers to break the speed limit. The situation would be ludicrous if it weren't so deadly serious. If Boston officials truly want safer streets, and I believe that they do, then it's time to reduce design speeds on all upcoming and future street plans. And for Beacon Street, it's long past time to re-stripe smaller and fewer lanes. That street may not be up for reconstruction for a while, but that's no excuse not to do some planter and paint-based interventions in the meantime.

A quote from the Globe:
Sam Wallace, president of the Neighborhood Association of Back Bay, who lives in a condominium at the scene of Saturday’s crash, said speeding has become commonplace recently and pedestrian safety in the area is a major concern among the residents.
“This is no longer Beacon Street; it’s the Indianapolis Speedway,” Wallace said. “The noise, the motorcycle races, the car races. And the later it gets, the worse it is.”
A flashing sign does nothing. The city must face the fact that Beacon Street, and many like it, are overbuilt in favor of speed. That is the problem that must be resolved.

Saturday, September 6, 2014

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.