Might does not make right

Years ago, when I was learning how to drive, my mother made sure to emphasize the fact that a motor vehicle is a lethal weapon. Nearly two tons of steel and plastic, moving at speed, is dangerous when misused or mishandled. That's not cause to be passive, but rather, to be cognizant of the consequences and continually vigilant. As a teenager, it was easy to get excited about the new power available to me, while not considering the risks, nor giving thought to others in the world around me -- except as obstacles. And like most Americans, I managed to make it through those years without serious incident, despite some mistakes, with the help of a few lucky breaks here and there. Because I was okay personally, I didn't think much beyond that, at the time.

Having spent several years on walking, bicycling and transit advocacy, I have a different, "outside-the-windshield" perspective on these matters nowadays. The power of the motor vehicle I can still appreciate, but I can also see how it is too easily abused. With one barely perceptible pedal push, a driver can blast past a child waiting at a crosswalk, and hardly notice at all. Or seeing brake lights ahead, a driver swerves to pass the one car that had yielded, and barely skims past a person crossing the street. The noise, grit, and grime caused by the passage of fast-moving motor vehicles is out-of-sight, out-of-mind to those drivers that create it. Even if nobody is physically harmed, the physical characteristics of living environments that facilitate speeding, heavy vehicles are unfriendly to human beings.

To behave humanely behind the wheel takes hard work, and a commitment to consider the other people around you. "Might does not make right" is the ethical principle that I believe is most applicable to transportation projects in our cities and towns. My feeling is that we have an obligation to protect the vulnerable from the powerful, and not only to protect, but to promote and serve. That is what forms the ethical basis of what I try to do.

The coalition of people who promote automobile interests are usually very strong, very rich, and very powerful. Motor vehicles are expensive to own, to maintain, and are highly wasteful of space. Any available room on the roads is quickly consumed by even a small increase in the number of vehicles. The resulting congestion can be enraging to drivers, as their expensive and powerful machines are trapped in a mire of their own making. At both home and destinations, without a readily accessible 300 square-foot piece of land for storage, these machines become a enormous burden on their owners, who then proceed to lash out in frustration.

Automobiles can provide convenient and quick transportation when everything works out, but when the systems quite frequently fail, the problems that stack up are often 'solved' at the expense of other people, especially the most vulnerable. Sidewalks are narrowed. Trees are cut down. Crosswalks eliminated. Bike facilities are completely omitted. Fences are put up. Transit is dis-invested. Highways are blasted through neighborhoods. Children aren't allowed to walk to school, or the park. Desperately needed housing development is canceled for imagined fear of "parking problems." Economic growth is stifled because "it might cause traffic." We can no longer properly build cities for people because all of our modern rules and regulations are designed to produce cities that only a machine could love.

Motor vehicles are powerful, and many of the people who own them are powerful. Motor vehicles are also very useful, and are a great boon to our civilization when used safely and prudently, within reasonable limits. But that does not make it right to give in to their every need. Without check they would take away our land, our natural resources, and the quality of our air. Thankfully, over the past several decades, the work of countless citizens has produced some legislative and political help, through endless community organizing. It's a continuing effort, and it's very important that everyone participate. Being obstructive is not enough: a great deal of damage was done by the Utopian automobile idealists of the 1950s who never gave any thought to the communities that were harmed by their schemes. That damage has yet to be repaired in many cases.

To give a concrete example: on June 17th, MassDOT will present the latest installment in the ongoing saga to rebuild the Allston Mass Pike interchange (6:30 pm, Jackson-Mann school). Fifty years ago, the Mass Pike extension widened the railroad right-of-way, taking houses, and leaving behind a huge scar across the Allston/Brighton neighborhood that has never been properly managed. The crossings are decrepit and crumbling, and not accessible to many people with disabilities. The streets that were rebuilt back then were given designs that had almost no consideration for people on foot, much less on bicycle. Dangerous highway ramps cut in at sections that seem to be designed to interstate highway-spec, despite being city streets.

Some bike lanes were painted in an effort to try and do something, anything at all, but despite the well-meaning effort, the street remains a major problem.

Two years ago, the Patrick administration announced a project that had the potential to fix all kinds of problems with the interchange. A dangerous curve in the highway would be straightened. The old-fashioned tollbooths would be replaced with modern, automated systems. The whole mess of city streets left behind by the 1960s extension project could be reworked, finally reuniting North Allston with south, and building a whole new neighborhood in between. And to top it off, a new 'West Station' on the Worcester line would finally give Allston back a railroad station somewhat near the site of the original station around which the community was founded.

But it seems that potential is being squandered. Despite months of community engagement and a professed commitment to "multi-modal thinking", the design team went off for the winter and nothing came out until finally this June meeting was announced with this plan shown, that seems to have more space allocated to roadway than non-roadway:

In the past year, the DOT design team told us often that they "don't do city planning" and it appears that they don't intend anyone else to do so either. It's hard to imagine anything neighborly fitting between those massive connectors (that will rise on earthen berms above grade, by the way). West Station is included, but can you imagine making the connection to or through that while walking precariously on a pathway above 10-12 lanes of roaring highway and some number of railyard tracks? This design is a highway design, engineered for the comfort of drivers first, and everyone else second. Yes, it's an improvement over the old ways, in that it will all satisfy accessibility regulations, and there are connected sidewalks and protected bike lanes. But with this car-first design, it seems that those facilities will only be used by necessity, not by choice.

We have often been told that "the computer models" require this many lanes, or that size an intersection, etc. The models, of course, have been programmed by engineers to try and predict the future. They say that they can tell us what the behavior of people in the year 2035 will be, with precision. They will tell us that unless they build all of this road space, we will be threatened by some kind of 'traffic armageddon'. It's a bullying tactic, plain and simple. Common sense should tell anyone that trying to predict the future is impossible, much less making precise predictions about conditions on a particular road 20 years from now. The models that they create are nothing but a set of equations and parameters chosen by the people who designed it. These models are as fallible as the people behind them, and can be used to say anything at all. Usually, they are used to say whatever it is the people who hired the modelers want them to say.

In this case, the powerful have spoken, and they have said that they want more automobile capacity in our neighborhood, at our expense. Whenever you hear an engineer say "the models predict increased traffic by X" what you should translate that to is "automobile interests want increased capacity by X, and nothing else matters."

Let's contrast this situation with what it might be like if MassDOT took the other side and tried to help provide space for a new neighborhood with good connections to the surroundings. Then the street network would be laid out at a human scale, with smaller blocks, smaller streets, and a collaboration with city planners in Boston. When it came time to talk about automobile capacity, instead of sending us an ultimatum that "we must tolerate a massive additional influx of vehicles or else", they would calculate the maximum capacity that is compatible with the city planning goals, and work to keep demand for the highway under that level. For example, perhaps it could be considered that commuter bus or train tickets should not be more expensive than paying the toll on the highway. Or that all employers that offer parking benefits must also offer 'parking cash-out' as a benefit for people who chose not to drive.

The reason that this way of working is so tough for them to do, politically, is because it requires that they go to the powerful automobile-promoting interests and tell them: there is a limit, and beyond that, demand for the road is going to have to be managed somehow. An ever-increasing level of traffic on the Mass Pike is not an inevitability. That will only happen so long as more capacity is forced on us, so long as officials are too timid to use the tools of transportation demand management to control the problem at its source, and so long as might makes the right-of-way.

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.

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.

Conclusion

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.

The Bowker Overpass and Storrow Drive

Who says we don't have Green Space here?

Over a year ago, I wrote about the Bowker Overpass which divides Kenmore from the Back Bay. MassDOT held a discussion about future options to deal with the overpass, but they seemed inclined to rebuild it, over the objections of residents. Now they are preparing to do $14 million repair project in Spring 2014. The public meeting was announced recently and will be on Monday, August 13th, 6 p.m. in the BPL Copley Mezzanine.

This is an unfortunate, though not entirely unexpected development. The Bowker Overpass crosses the Mass Pike and covers the Charlesgate Park: once the "crown jewel" of Olmsted's Emerald Necklace; now reduced to an overgrown, weedy hideout for bums.

The portion over the Mass Pike can't be escaped, but the overpass of Charlesgate Park is actually redundant with the surface roads. It was built at a time when grade-separation was all the rage: the 1950s and the heady days of highways. The Bowker Overpass combines with a spaghetti mess of ramps to interchange with Storrow Drive: consuming large portions of the Esplanade which never should have been taken in the first place.



Mostly unusable "greenspace" due to the ramps (google)
All of this was constructed before the Mass Pike was extended into downtown Boston. It has not aged well. Storrow Drive is decrepit, a blight on the city that acts as a barrier between Boston and the Charles River. The Storrow Drive tunnel/double-deck roadway is in miserable shape; it was even recently rated the Most Dangerous Bridge in the country. Repairing the Bowker Overpass without talking about the Storrow Drive tunnel is irresponsible.

The fact is: the city and MassDOT need to have a serious conversation about grounding Storrow Drive. The 1950s grade-separations are falling apart: they have long exceeded their lifetimes and were not properly maintained either. And we should not shackle ourselves to outdated 1950s ideas about automobiles and the city. It is not such a fascinating idea anymore that you could drive your car on swirling ramps through the air to avoid intersections. Nowadays, we're more focused on connectivity, and accessibility; two things which grade-separation is bad at achieving within reasonable expense.

Once you manage to get on the grade-separated Storrow Drive, you're essentially trapped. You have very poor access to the various streets in Beacon Hill, the Back Bay, Kenmore, or Allston. And there are very few places to cross the highway: so if you are looking to spend time near the river, you have to find one of the few bridges across. This also hurts safety: poor connectivity leads to fewer "eyes on the park" at night, and makes it harder for police to patrol the area.

Grounding Storrow Drive and the Bowker Overpass could achieve many things:

1. Rid us of a festering sore under the overpass.
2. Restore a ton of parkland currently cordoned by ramps.
3. Connect the Esplanade more closely to the city, increasing accessibility and safety.
4. Connect more of the street grid to Storrow Drive, easing access for all modes.
5. Save a boatload of money not rebuilding the $300+ million separation structures.
6. Reduce construction nightmare that rebuilding the Storrow tunnel would entail.

What's the catch? Well, it might take a little bit longer to drive to your destination via the same route you used in the past. On the other hand, you might also save a lot of time by not having to go around and around in loops on one-way streets. I know that some traffic engineers will be screaming that this represents a "downgrade" but they can take that attitude back to the 1950s where it came from. For the rest of us, this would represent an upgrade: a better city. Plus, $300 million saved! Heck maybe more. I suspect that any attempt to replace the Storrow tunnel will quickly turn into it's own "little Big Dig" with rapidly inflating costs. That's a lot of money that could be put into so many other, better, actual improvements. Like making the MBTA an attractive option for people who currently feel like they have no alternative but to drive along this way.

How MassDOT approaches the impending dilemma of the Bowker Overpass and the related Storrow Drive tunnels will tell if they are really serious about their "GreenDOT" proposal or not.

The replacement of the Cambridge Street overpass of I-90

MassDOT has decided to expedite project 606376 to replace the deck of an overpass of the Mass Pike that is located in Allston, along Cambridge Street. The plans are already in 100% design state because they have been sitting around for a few years. However, they are offering a chance to comment over the next ten days, and at Tuesday's public meeting, they pledged to incorporate suggestions if possible. This is probably a once-in-a-generation opportunity to help fix a blight that has plagued Allston since the construction of the Mass Pike extension in the mid-60s.

[The comment period for all this is now, ending by July 3rd. Please e-mail dot.feedback.highway@state.ma.us and reference the Cambridge Street overpass over I-90 project number 606376. You may also read more on http://cambridgestreetoverpass.blogspot.com/.]

View Larger map (final design bus stops shown as blue markers)
The project scope extends from the intersection with Harvard Avenue in the west, to the intersection with Lincoln Street in the east. It also includes several minor repairs to the pedestrian footbridge across the pike at Franklin Street, but nothing more significant. MassDOT has suddenly gotten interested in this plan after it languished for several years, because the deck is deteriorating to the point where replacement must happen within the next couple of years. Conditions above the deck have been nearly intolerable for the past few years as well.

The sidewalk is fenced off because it has gaping holes

Dangerous conditions

A little history: prior to the construction of the Mass Pike extension in the mid 1960s, Cambridge Street had a smaller overpass of the Boston and Albany railroad. Lincoln Street, Mansfield Street, and Royal Street all connected directly to Cambridge Street.

Cambridge Street in 1925

The construction of the highway meant widening the right-of-way. Homes along the south side of Lincoln Street were taken (including Fred Salvucci's grandmother's home), as well as some homes on Mansfield and Royal, and the streets were reconfigured. Lincoln Street was redirected to curve to the northeast, paralleling the new highway. The ends of Mansfield and Royal were chopped off and reconnected to Lincoln Street. Then, Lincoln Street was rerouted over the Empire Street right of way and re-attached to Cambridge Street where Mayflower Street is shown on the map above. The net effect was to sever the street grid and create an overly long, uninterrupted block from Linden Street to the new Lincoln Street intersection. Motorists treat this stretch as if it were part of the highway, racing at high speeds along the excessive capacity, and creating a scary environment for anyone not surrounded by 2 tons of steel.

Eagle-eyed readers will notice there is a "tunnel" marking by Franklin Street. This was the location of a 19th century grade-separated walkway under the tracks. This was covered over and replaced in the 1960s by the current Franklin Street pedestrian overpass, which connects a point opposite Highgate Street on the south side, with Franklin Street on the north side.

The Cambridge Street berm

There is also a ramp at Mansfield Street, to replace the street connection that once existed. It climbs the berm so that people walking from Mansfield Street can reach Cambridge Street directly.

The Cambridge Street overpass of I-90 was given six lanes of automobile travel, small sidewalks, and no safe means of crossing, over 45 years ago. It has remained so since, but the bridge deck has reached the end of its lifespan and must be replaced.

Both MassDOT and BTD have shown a willingness to improve conditions on the bridge for walking and bicycling. They have recognized that six travel lanes is massive overkill: the feeder streets only have one lane in each direction, so there is simply not enough connecting capacity to fill six lanes anyway. As a result, they have drawn up buffered bike lanes and wider sidewalks into the current plans.

Crossing Cambridge Street

Unfortunately, in the same plans, they have decided to place a quarter-mile long fence right down the middle of Cambridge Street, from end-to-end of the scope. The claim is that they are concerned about "safety":  many people trying to get between North and South Allston are unwilling to walk a half-mile out of their way to use one of the intersections. So, instead of providing safe places to cross the street, the state agency is simply try to block all crossing. But that's unacceptable to the community. We need north-south permeability here. The sheer number of people willing to walk down the center median and climb the current concrete barrier attests to that. Many of these people live in North Allston and need to access jobs, shopping or bus stops in South Allston. Others live in South Allston and want to reach neighborhood resources in North Allston. MassDOT needs to accept that north-south travel is just as valid as east-west travel on this city street.

Now, MassDOT wants to stick to their scope and their schedule because they feel hurried to get this done. I also agree that this project needs to get done as soon as possible. So this comment period will likely be the last chance to ask for improvements in the final design.

What's exciting about this project is that the city has apparently been making plans quietly for a kind of "corridor to the river" from Allston to the Charles that uses Cambridge Street. For many decades, this street has been a barrier to walking and biking, with dangerous highway ramps and speeding trucks, but it could be transformed into a gateway instead.



View Cambridge Street corridor to the river in a larger map
The River Street Bridge replacement project (shown in blue) will be underway right after the Anderson bridge is complete. So, after that, the missing piece is in the middle: Cambridge Street.

• Cambridge Street is a city street, and should look and feel like a city street, not a "mini-highway."
• MassDOT and BTD are both onboard, in principle, with fixing Cambridge Street and building this "corridor to the river" but they seem to be fragmented in planning. Management of the corridor is split between the two agencies. We need them to be on the same page so that the final outcome is coherent.
• A quarter-mile long fence with no crossings is not acceptable to the Allston community. There needs to be a safe place to cross. Some possibilities include the Linden Street intersection, or the Mansfield Street stairs. It should be possible to put a coordinated traffic signal at Linden Street which helps crossing with no impact on motor traffic.
• During construction, a 2 year period, portions of the bridge will be closed. There will be three phases: each third of the bridge will be shutdown and replaced, from north to south. Although I understand that there will be unavoidable impacts, MassDOT needs to ensure that non-motorized access is considered seriously during this time-frame.
• The Franklin Street overpass attracts heavy foot and bicycle traffic, which must share a narrow sidewalk along the north side of Cambridge Street near Harvard Avenue. The MassDOT plans call for directing the bicycle lane up a ramp and onto that same sidewalk. It will be widened to 13 feet, but, it turns MassDOT engineers had not anticipated that there currently is (and will be) 2-way bicycle traffic on this segment because of the overpass. Luckily, there is a grassy strip adjacent to the sidewalk which could be taken for a sidewalk-widening easement. That needs to be considered.

Two bicycles take up all the space already; but look at that potential width!

The comment period for all this is now, ending by July 3rd. Please e-mail dot.feedback.highway@state.ma.us and reference the Cambridge Street overpass over I-90 project number 606376. Or you may write a letter to:

Thomas F. Broderick, P.E., Chief Engineer

MassDOT - Highway Division

Attn: Bridge Project Management

10 Park Plaza

Boston, MA 02116-3973

You may also read more, including the 100% design plans, on http://cambridgestreetoverpass.blogspot.com/.

"There is a very strong element of psychology behind traffic patterns."

I checked back in on the so-called "Carmageddon" of late 2012 -- the closure of one lane of the Alexander Hamilton Bridge from Manhattan to the Bronx -- to see how it panned out. From the Bergen Record, Warnings staved off traffic gridlock from George Washington Bridge. Quote (italics added):

It was supposed to be a traffic nightmare. It turned out to be a dream. 

Predictions of five-mile backups and unprecedented delays on the New Jersey side of the George Washington Bridge appear to have scared thousands of daily commuters away from the span. Except for the recent congestion caused by superstorm Sandy’s assault on the region’s transit system, motorists have seen faster-than-normal rush-hour commutes ever since the July start of a major construction project in New York City, according to transportation officials, experts and traffic data. 

“We see this time and time again,” said Jim Bak, director of community relations at INRIX, a company that collects data on traffic along the Interstate 95 corridor and other highways throughout the country. “There is a very strong element of psychology behind traffic patterns.” 

In the last few years, he said, similar worst-case warnings in Los Angeles, Seattle and London have had the same effect — actually reducing traffic to below-normal levels on roads that were expected to be clogged. It’s a public relations strategy that state transportation officials in New York, who aired the predictions in media outlets throughout the region before the July 15 start of the project, acknowledge opens them to “cry wolf” criticism. But they say there was no effort to mislead the public and that the backups might have matched predictions if people hadn’t changed their routines.

 They called it "crying wolf," I called it "Henny Penny." Same difference. More:

At 8 a.m. on a typical weekday, it takes 11 to 13 minutes on average for a vehicle to travel eastbound from the intersection of Routes 80 and 95 in Hackensack to the deck of the George Washington Bridge, according to INRIX. But in the months from the start of the Alexander Hamilton Bridge project until Sandy struck, that drive took an average of between four and six minutes.

There were nearly 6,400 fewer daily Manhattan-bound trips on average in the 2.5 months after the July 15 start of construction, compared with the period in 2011, according to officials at the Port Authority of New York and New Jersey, the agency that operates the GWB. They also said the warnings appeared to be the cause.

The Lincoln and Holland tunnels, the Port Authority’s other Hudson River crossings, meanwhile, saw no appreciable increase in traffic over that time, said Steve Coleman, a spokes¬man at agency.

I'll note that while the original over-hyped, alarmist coverage of the closure was widespread, the follow-up report was buried and barely noticed.

Obviously this fits well with their public relations strategy if they are intentionally raising the alarm in an effort to manipulate traffic patterns. It wouldn't do for the public to grow wise to their scheme, would it?

The Casey Overpass (source)

But as a result, the public still believes in doomsday predictions when it comes time to discuss the closure of collapsing highways and outdated overpasses. Cries of "gridlock!" and "nightmare!" fly at public meetings. Local residents form a sort of "Stockholm Syndrome" attachment to the 1950s era infrastructure which mutilated their community. There's a great fear of bringing the roadways back to human scale because the supposedly trustworthy officials have spent so many years scaring the public with outlandish claims of impending disaster.

At other meetings, folks stand up and protest against new development -- housing that is so desperately needed, commercial space to attract more jobs -- because they were told it would "worsen congestion." The consultants are stifled by their very own ridiculously oversimplified "level of service" metric which labels intersections with "A" to "F" letter grades. The residents want to know why the wonks aren't doing their homework well enough: surely they could get a better grade if only they put in the effort?

In both cases, we need more honesty from traffic engineers and city officials in charge of transportation. The first step is to make it clear that "Traffic is NOT like water." There is no "strong element of psychology" dictating how water flows, so that analogy simply breaks down. The honesty starts when traffic engineers stand up and admit that motorists adapt to real world conditions, that there are complicated feedback processes which are extremely difficult to model, and that it is not an exact science.

The use of "level of service." Credit: Andy Singer (source)

Traffic engineers need to admit that the letter grades given out by "level of service" are extremely misleading. What the grades really measure is the volume of cars using the roads and intersections, not the amount of "work" that an engineer does. They can tinker around the margins but the core cause of an "F" grade is that there are too many cars trying to get through that space. There is only one way to accommodate all those cars: increase the number of lanes. This is how "level of service" was often used in the past: to justify the widening of roads, the creation of grade separations, and the destruction of the communities around them. In many cases, the road widening induced even more demand than before, leaving the area just as congested and more miserable than ever.

Since road widening is no longer acceptable in urban communities, there is only one other choice available: to manage demand. Instead of holding communities hostage to dictated traffic projections, often based on false premises, the communities need to turn that around and stake out what street design is acceptable and what is not. Then the traffic engineers come in as public servants, not masters, and make the safest, best use of the allotted space. Streets are supposed to connect communities, not divide them.

Demand management goes further than that. Unintentionally, the officials in New York have demonstrated a certain principle: If you increase the perceived cost of a particular route, then traffic will decrease on that route. In the case of the Alexander Hamilton Bridge closure, the officials went out of their way to scare people into thinking that there would be an increased "time cost" for going over the George Washington Bridge. It worked. But we don't need to create crises to manage demand. There's a natural way to do it, the same way we manage demand in nearly all other contexts: putting a price to valuable road space. It's been demonstrated to work well in London, Stockholm, and Singapore, as well as other places. And it's the only real solution to congestion.

There's other tools in the demand management box: designing streets so that people feel comfortable walking or biking instead of getting into a car; improving public transportation; building communities where distances are at human-scale instead of at automobile-scale; and reducing the number of parking spaces. These strategies don't directly attack congestion the way road pricing does -- and may not appear to reduce congestion at all. But they do enable more people to live and get around without struggling constantly against congestion.

It is generally not possible to "solve congestion" non-destructively without demand management, in an urban environment. The reason is simple geometry. In a city, most any destination of significance will attract more people than roadways could handle if they all came in cars. There just isn't enough space. The cars that do attempt to come will quickly fill up the available space, and people will call it congestion. It will be congested if few people walk there, and it could still be congested even if most people walk there. Because as long as the demand exists, available slots will be filled with cars, no matter how well the roadways are designed.

The geometry problem, illustrated (source)

These days, most large projects filed with the BRA include a "Transportation Demand Management" section. They tend to use similar language (copy-n-paste is my bet) and say nice things about getting their employees to walk, bike or use transit. And it's all well and good to get people thinking about this. Developers claim the standard is to "mitigate their own impacts." But individual developers can't do much. They are usually asked to tinker with signal timing at nearby intersections, or redesign some street flows.

But that can only go so far. Real action has to be taken at a larger level; maybe community-wide, maybe city-wide, maybe even region-wide. This is because the key factors driving road demand are coming from those levels. For example, zoning rules which dictate "minimum parking requirements" cause traffic to increase in the vicinity of new developments. Zoning rules which force communities to sprawl cause people to use their cars more. Zoning rules which make for miserable streets discourage walking. The construction or widening of a nearby highway induces additional demand on the roads leading to that highway. The deterioration of public transportation forces people to resort to automobiles. And the implementation of road pricing will have to come about through action by elected officials and activism by local advocates.

The first step is honesty from the experts and the transportation officials serving us. The answers are not easy. Many won't want to hear them. But we should demand them.

Boston MPO memo fails to understand purpose of HOV lanes

The Boston MPO recently released a memo titled Screening Regional Express Highways for Possible Preferential Lane Implementation. Quote:

The preferential lanes envisioned in this study would usually constitute specialized, separate lanes, generally constructed in the median of an expressway. The adjacent main travel lanes could continue to accommodate their full lane capacities, up to around 2,200 vehicles per hour, depending on the design standards of the roadway. With preferential lane eligibility set to allow fewer vehicles, perhaps 1,500 per hour, buses and other users of the preferential lane would be able to travel at posted speeds. Depending on traffic conditions, users of the general-purpose lanes would continue to experience delays either as a result of heavy traffic or from queues forming at bottlenecks.

It is sometimes suggested that an HOV lane could be implemented by converting a general-purpose lane for the exclusive use of HOVs. Since it is assumed that any preferential lane eligibility rules would result in fewer vehicles in the preferential lane than in the general-purpose lanes, the result would be a reduction in total expressway capacity. Reducing the capacity of a congested expressway would seriously worsen congestion and queuing within and leading to the capacity-reduced corridor, as well as on nearby surface roadways.

Here's the author's reasoning:

• General purpose lanes have a capacity of 2,200 vehicles per hour
• HOV/preferential lanes should be limited to 1,500 vehicles per hour
• 1,500 is less than 2,200
• Therefore, general-purpose lanes should never be converted to HOV lanes.

Have you spotted the flaw yet? It's the measurement unit: vehicles per hour. The author considers that all vehicles are equal with regards to congestion. Therefore a single-occupancy car is equal to a four-person carpool, and both are considered equal to a bus carrying 50 people. This memo blithely ignores the entire purpose of HOV lanes -- which is to expedite the movement of people, not pieces of metal.

Induced demand in the 1930s

Let's take another look through the many-faceted opus, The Power Broker.

Anytime someone makes the excuse that "we need to widen the roads and build more parking lots to accommodate all the cars using it" just remind them that building more infrastructure for cars causes more traffic. This effect was noticed as early as the 1930s. Robert Caro vividly describes the effect of the earliest fully-grade-separated highways on New York:

Grand Central Parkway on a nice day (source)

The Grand Central, Interborough, and Laurelton parkways opened early in the summer of 1936 [...] One editorial opined that the new parkways would, by relieving the traffic load on the Southern and Northern State parkways, solve the problem of access to Moses' Long Island parks "for generations." 

The new parkways solved the problem for about three weeks. "It wasn't more than three weeks after they opened that I decided to go out to Jones Beach on a Sunday," Paul Windels recalls. "I got on the Interborough and by God it was as jammed as the Southern State ever was." Moses announced that he had the solution: build forty-five miles of new parkways [...] 

Some city planners noticed that the traffic pattern on Long Island had fallen into a set pattern: every time a new parkway was built, it quickly became jammed with traffic, but the load on the old parkways was not significantly relieved. If this had been the pattern for the first hundred miles of parkways, they wondered, might it not be the pattern for the next forty-five as well? [p. 515]

But when they suggested improved mass transit ideas that groups such as the Regional Plan Association had been proposing, they were ignored.

The approach to one span of the Triborough (aka RFK) Bridge (source)

The Triborough Bridge opened on July 11, 1936. [...]

On August 17, 1936, a little more than a month after the Triborough Bridge opened, Long Island's parkways were the scene of what some observers called the greatest traffic tie-up in the history of the metropolitan area. 

Referring to it as a "cross-country traffic jam," the Herald Tribune was forced to conclude that the bridge had, at least indirectly, caused it. [...]

Despite the heavy volume on the Triborough Bridge, Othmar Ammann [the chief engineer] said, "the relief of the traffic load on the Queensborough Bridge has not been as great as expected." But the Times editors evidently did not consider this fact particularly noteworthy. [...]

Traffic between Long Island and New York had, before Triborough's opening, flooded the twenty-two lanes available on the four old bridges; suddenly the traffic between Long Island and New York had become so heavy that it was also flooding eight new lanes, the new lanes of the Triborough Bridge---and it was hardly any lighter than before on the old bridges. [p. 518]

Again, Moses called for more parkways and what would become the Long Island Expressway. And again, the press went along with it.

The Wantagh State Parkway Extension was opened on December 17, 1938, three months ahead of schedule. [...] 

[It] did not receive its first real test of traffic-easing capacity until the first warm weekend morning of 1939. On that morning, it was jammed bumper to bumper for more than three miles. Traffic experts could not understand where those cars had come from. The other Long Island parkways, after all, were just as jammed as ever. [p. 517]

Having observed the problems, the RPA attempted to get provisions for a railroad link included on the proposed Bronx-Whitestone bridge. Moses refused to consider it.

The Bronx-Whitestone Bridge (source)

During 1940, the first full year of operation, 6,317,489 vehicles passed through the Bronx-Whitestone's toll booths, cramming its four lanes to capacity and causing massive tie-ups on it. Traffic on the Triborough was reduced by 122,519 vehicles. Traffic on the other four East River bridges was reduced not at all. In fact, it rose slightly. Somehow the new bridge had generated, in a single year, more than 6,000,000 new on-and-off-Island motor trips. [...]

Shortly after the bridge opened, Moses completed the road linking the bridge with Westchester County, the Hutchinson River Parkway. Soon, that was jammed too. [p.519]

At this point the book turns to the Gowanus Parkway, an elevated highway which ripped through the thriving Brooklyn neighborhood of Sunset Park, and destroyed the heart of it on Third Avenue. It replaced the elevated train line of Third Avenue which was supposed to be taken down in favor of the newly constructed Fourth Avenue subway. Instead it was replaced by a massive concrete elevated highway and the four lane avenue beneath was widened into a 10-lane road to carry the trucks which Moses would not allow on his "parkway."



Below the Gowanus Expressway (formerly Parkway) (source)

The construction of the Gowanus Parkway, laying a concrete slab on top of lively, bustling Third Avenue, buried the avenue in shadow, and when the parkway was completed, the avenue was cast forever in darkness and gloom, and its bustle and life were forever gone. [...] Stores, restaurants and theaters had brought people to Third Avenue. Now half the stores, restaurants and theaters were gone.

The El had brought people through Third Avenue on their way to and from its stations. The parkway did not. Moreover, although the El had been a huge, gloomy structure, it was, as Cathy Wylde puts it, "one that people from the neighborhood relate to; they traveled on it, they were familiar with it." [...] "The highway was something different," Miss Wylde says. "It was noise, dirt, accidents, not lighted, a garbage dump, drag races along it in the night, wild kids, something totally negative. It was a tremendous psychological barrier. In a way you could say the people feared the highway." [...] Once the avenue had been a place for people; Robert Moses had made it into a place for cars. And as the avenue's roadway became more crowded, its sidewalks began to empty. [p. 523]

No sooner would Moses open the Brooklyn-Battery Tunnel at one end of the Gowanus Parkway and the Belt Parkway at the other than the Gowanus would be jammed solid with traffic. At rush hours, the traffic trying to get up onto it would be backed up solid, spilling off the ramps and back into the neighborhood for blocks. [p. 525]

Merging into the Henry Hudson Parkway from the George Washington Bridge (source)

But quite possibly the largest project of this time period was the so-called West Side Improvement: the Henry Hudson bridge at the northernmost tip of Manhattan and the parkway connecting to the West Side Elevated Highway at 72nd Street. Moses claimed it only cost $24 million at the time, a figure wildly out of line with reality. Robert Caro estimates that the true cost was between $180 and $218 million in 1937, which would probably fall somewhere between $3,000 and $4,000 million in 2012 dollars. Besides the highway he did create a linear park, although much of it was blocked from the riverside by the highway. And the park suddenly vanishes when it reaches the part of Manhattan with the highest minority population at the time (Moses' racism is a whole topic unto itself). But we are on the topic of induced demand, so what happened with the West Side Improvement? No surprise to us:

Motorists pulling up to pay their tolls found themselves at the end of lines that seemed little, if any, shorter than the lines had been at the old Broadway bridge, whose congestion New York had considered intolerable. And there was another puzzling fact. Although the new bridge had been built to relieve the congestion on the old bridge, congestion on the old bridge had not been noticeably relieved. The lines of cars waiting to cross it were, in fact, almost as long as ever. [...]

The rush-hour jams were just as bad as the rush-hour jams had been on Riverside Drive before the West Side Improvement was built; reporters escorted over the West Side Improvement before it opened had found it reduced the time required for the nine-mile trip from sixty-eight minutes to twenty-six; now one of those reporters made the trip over the West Side Improvement at two rush hours---admittedly very bad ones---and found that on one trip it took fifty-eight minutes, on the other seventy-three. And looking at the situation that way, the total effect on traffic congestion of the West Side Improvement had been to move the congestion one block west---and yet there was still congestion on Riverside Drive, congestion that had been eased only slightly by the construction of a parallel route. [p. 563]

The Zakim Bridge leading into the Central Artery/Tunnel

Did we learn our lesson from this exercise in wasteful spending for little benefit and heavy cost to quality of life? Of course not. The Big Dig cost $15 billion before interest, and this is what the Boston Globe had to say about induced demand when they did some investigation:

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 Greenway boulevard atop the Central Artery/Tunnel

But hey, at least downtown's not covered by the Green Monster anymore, right? That's got to be worth something. Not $15 billion though. And not for a highway which should not have been built in the first place. The correct answer would have been to take it down and---at a fraction of the cost---replace it with a more appropriate boulevard having its congestion managed through pricing. Well, now the money's been spent, and in fact, we got the worst of both options: the above-ground boulevard stinks up the Greenway and the tunnel funnels cars into new chokepoints around the city. Oops.

Back in New York State, Governor Cuomo is attempting to force through a new Tappan Zee bridge that---like the Bronx-Whitestone---lacks bus lanes or railroad provisions. He even compared himself to Robert Moses at one point. The opposition is stronger this time, but it's an open question who will prevail.

Part of the Bowker Overpass

Much of the 1950s automobile infrastructure in Metro Boston is decaying and coming to end-of-life. It could easily cost hundreds of millions, or even billions, of dollars to repair deteriorating tunnels and bridges. With the issue of transportation funding in the air, the fact shouldn't be lost that it is not worthwhile to restore these facilities to their 1950 state. We should not be held hostage to "traffic projections" when history so clearly shows that traffic is induced by the existence of these facilities in the first place. The roads have to be fixed in some way, as in many cases they are beyond repair. We could save a whole lot of money by choosing more appropriate, scaled-down designs which integrate with the city and improve quality of life for residents as well as visitors.

As for The Power Broker, there's tons more great material to sort through, I had to pare down quite a lot of excellent prose to keep the length of this post from becoming overwhelming. So I recommend checking it out yourself. Most of the quotes are from the first chapters of Part V, The Love of Power.