Bus Rapid Transit

Portland: Good Outcomes from “BRT-Lite”

Photo: TriMet

Portland’s transit agency TriMet has some good news to report from its “light Bus Rapid Transit” project on Division St.  It’s especially good news because lots of North American cities have streets that look like Division, namely:

  • A segment of a few miles through the inner part of the city where the street is too narrow for bus lanes, but where redevelopment is driving up densities and thus travel demand.  This part of Division is increasingly lined with four story buildings — residential over retail — with historic small-lot single family homes behind them.
  • An outer segment in “inner ring suburbia” where the street is wide enough for bus lanes, and where the critical issue is the unsafe environment for pedestrians.

The Division FX project consisted of the following changes, probably in roughly declining order of importance.

  • Wider spacing of stops (up to 1/2 mile in some places) with no underlying local-stop service alongside it.
  • A 12-minute frequency, instead of the usual 15 for Frequent Service Network lines.
  • Signal priority at signals along the line.
  • Improvements to sidewalks and pedestrian crossings in the outer segment.
  • A short stretch of bus lane in the area that had room for one.
  • Articulated buses (60 feet long, with a hinge).
  • Nicer shelters with signage identifying the location and a realtime information display.
  • A special green paint scheme.

But it’s still in mixed traffic on the narrow and congested inner segment.  There was a lot of reason to doubt how much improvement could be achieved in that situation.

So I’m pretty impressed with the results:  Overall travel times are up to 20% shorter.  That’s 20% more access to opportunity for people traveling along the line.  And of course, this line is part of a frequent grid, which spreads these benefits over this whole side of the city.

Ridership is up dramatically as a result, almost 40% for the first year of operation (September 2022 – August 2023) compared to the year before.  Total transit system ridership grew about 8% over that time, so some of this is background growth due to ongoing pandemic recovery.  But still, even if the effect of these changes were only a 30% increase, that would be spectacular.

There are many, many streets like Division where this quality of service is needed and possible.  I hope we can aspire to a time when all frequent bus lines have at least this level of quality.

 

 

Basics: Should Bus Rapid Transit be Open or Closed?

If you are involved in debates about Bus Rapid Transit, you need to think about whether the project will be closed or open, because this will have a big effect on how useful the service is.  I’m always surprised at how few BRT projects clearly debate this issue.

A BRT system is open if the buses can continue off the end of the infrastructure and operate as conventional buses on local streets.  In situations where multiple bus operating companies run along the same path, open can also mean that the infrastructure can be available to multiple operators, although that almost always implies the first meaning as well.

A BRT system is closed if the buses must remain with the infrastructure, so that service must end at the end of the infrastructure, just as all rail services do.

In a given situation, a closed BRT option will require more transferring than open BRT for people to reach actual destinations that lie beyond the infrastructure.  As a result, it will tend to lead to longer overall travel times unless the speed advantages of the BRT compensate for that transfer delay.

There are two reasons this is a problem for your actual ability to go places:

  • A very single-centered urban form may logically need services to branch as they head out of the city, because as demand gets lower, you need less frequency but needed to cover more area.  Branching divides frequency, and in that case this can be OK.
  • But the bigger problem is that for non-transit reasons, the infrastructure may end where the demand doesn’t end, and closed BRT in this situation forces a lot of people to transfer just to keep going in the same direction.  In a high-frequency grid, for example, it’s important that service operate continuously all the way across the grid, so that while some people will have to transfer once few have to transfer twice.  Closed BRT can be an obstacle to this.

Despite this disadvantage, BRT systems are often closed for two major reasons:

  • In extremely crowded systems, closed BRT allows for tighter control of operations, for maximum capacity and minimum waiting time.  Capacity considerations may also dictate that all buses using the infrastructure be as large as possible.
  • In wealthy countries closed BRT more likely to be about trying to mimic the experience of rail transit, so as to be more attractive to a supposed discretionary or “choice” rider. If the goal is to make BRT appear special and different from regular buses, this goal is muddied if BRT buses run outside the infrastructure, or regular buses run inside of it.

The first of these reasons translates into measurable benefits in travel time, and thus access to opportunity, while the second does not.

Closed BRT is the more common kind of BRT in the United States, mostly for the second reason.  Where it appears in developing countries with very high public transit demand, it is mostly for the first reason.

BRT can be closed by any of three design choices:

  • Station and fleet incompatibility. Stations and buses may be designed so that they can only be used together.  For example, Eugene, Oregon’s BRT can run in regular lanes and even in mixed traffic, but its stations have high platforms that only match the floor height of the designated BRT buses, effectively requiring a closed system.  Fleet incompatibility can also be created through electrification, especially if end-of-line charging stations are required.  These stations become barriers to continuing service beyond the end of the line at that station, because the charging requires an amount of time that is practical only at the end of the line when no passengers are on board.
  • Full separation. It can be made physically impossible for buses to enter or leave the infrastructure.    This is very unusual, since buses may need to enter or leave in emergencies or to travel to and from the operating base.
  • Operating plan. Service can be operated as closed even though the infrastructure doesn’t physically prevent open operations.

So should a new BRT system be open or closed?

In most cases, the advantages of open BRT are about people being able to go places so they can do things.  The advantages of closed BRT are mostly about branding and some limited kinds of amenity.

Brisbane, Australia’s BRT system uses ordinary buses that continue onto local streets, but it’s still really, really nice.

The concept of amenity is worth unpacking.  Many great amenities are possible on open BRT – see the beautiful busway stations of Brisbane, for example – but these generally do not include special buses with special features, unless you buy enough of these that they can continue to wherever those buses logically need to go to create the most liberating possible network.  There’s another reason to be cautious about special buses: Really, all buses should be nice, so creating a distinct brand of buses amounts to disparaging the rest of the bus system as much as it’s promoting the BRT.   We may be spending a lot of capital money to promote the idea that most buses are inferior.

But a few things, such as absolutely level boarding, benefit from buses that stop exactly at the platform level, and these buses tend not to be able to stop an ordinary bus stop.  Absolutely level boarding is great, and especially important to people using mobility devices.   But well-designed open BRT, with good operations and training, can still do reasonably level boarding where it’s easy to cross with a wheelchair or stroller.

I said “in most cases,” open BRT offers the best travel times and thus the most access to opportunity.  So what are the exceptions?  Closed BRT can be more efficient at very, very high levels of ridership – such as we see in big cities in less wealthy countries.  Here, an entire corridor may be continuously very busy, and in this case, the most efficient operations, and hence highest capacity, arise from being able to use every bit of the infrastructure and keep buses evenly spaced.  This is harder to do with open BRT, because buses may be entering or leaving the infrastructure part way, thus leaving a part of the infrastructure with fewer buses.  Buses may also be entering unpredictably, because they are coming from route segments where they are running in mixed traffic and thus subject to delay.  Where such huge volumes of people are traveling, these problems can cause pass-ups that do measurably reduce travel.

But this important exception arises only where massive capacity is critical, and this case rarely arises in the moderate-density wealthy countries of North America, Australia/New Zealand, or even most of Europe.  So in those countries tends not to offer any advantage to people’s ability to go places so they can do things.  In these contexts, closed BRT can deliver a better “brand” or “look and feel”, but open BRT is more likely to get you to our destination as soon as possible.  You decide which matters more.

Albuquerque: A Rare “Gold” BRT

Albuquerque’s new Bus Rapid Transit (BRT) line is open, and it’s different from most such projects that we’re seeing in US cities of similar size.  Quite simply, most of it is protected from traffic congestion, thanks to a median bus-only lane.  It’s the red segment (with green stations) on this map (full map here)

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Albuquerque BRT alignment. Red with green stations denotes exclusive bus lanes.

This is why it’s being called a “Gold” standard right of way by the global Institute for Transport and Development Policy (ITDP).  ITDP Gold is not just another feel-g0od award; it has a specific meaning in their international BRT standard, and the core point is protection from traffic.

ABQ BRT station

Yes, the lanes are red. No excuse for not seeing them. (Photo: Albuquerque Rapid Transit, http://www.brtabq.com/)

Many, many US BRT projects start out with exclusive lanes, but then make too many compromises along the way.  In the worst cases, they end up as a bunch of nice infrastructure but little or no improvement in travel times.  My own view is that if a bus does not have protection from traffic in the segments where it is needed to deliver a reliable operation, then it’s not BRT.  For example, Las Vegas has a fine segment of busway that delivers buses from the traffic jam of downtown to the traffic jam of the Las Vegas Strip, but it doesn’t exist where it’s most needed, which is to get through those jams.

Albuquerque’s looks like a breakthrough in this regard.

And no, it’s not a problem that the buses continue beyond the end of the right of way to do further things in mixed traffic at the east end of the line.  One of the great virtues of BRT is that it can do this.  The vehicles are not confined to the infrastructure, as rail transit is, so they can continue to key destinations beyond the busway itself.  Of course, if those mixed traffic segments become too congested, the busway will eventually need to be extended further.

So congratulations to Albuquerque.  It looks like the opening day went well.  I hope the system helps other cities see the benefits of not compromising on the most critical element of BRT — protection from traffic delay.

Portland’s Division Transit Project: A New Kind of “Rapid” Urban Bus

For the past few years, planners at the transit agency TriMet and MPO Metro in Portland have been carefully shepherding the development of a new sort of transit project for the city.  It’s turning into a new sort of transit project, period — one that doesn’t fit in the usual categories and that we will need a new word for.

The Powell-Division Transit and Development Project extends from downtown across Portland’s dense inner east side and then onward into “inner ring suburb” fabric of East Portland — now generally the lowest-income part of the region– ending at the edge city of Gresham.  It was initially conceived as a Bus Rapid Transit (BRT) line, though one without much exclusive lane.  It would be a new east-west rapid element in Portland’s high-frequency grid, and also serves a community college and several commercial districts.

(Full disclosure: JWA assisted with a single workshop on this project back in 2015, but we haven’t been involved in over a year.).

Below is a map of how the project had evolved by 2015, with several routing choices still undetermined.  From downtown it was to cross the new Tilikum bridge and follow Powell Blvd. for a while  Ironically, as inner eastside Portland began to be rethought for pedestrians and bicycles, decades ago, Powell was always the street that would “still be for cars.”   To find most of the area’s gas stations and drive-through fast food, head for Powell.  As a result, it’s the fastest and widest of the streets remaining, but correspondingly the least pleasant for pedestrians.

Half a mile north is Division Street.  For the first few miles out of downtown, Division is a two lane mainstreet, and it’s exploded with development.  It’s on the way to being built almost continuously at three stories.  Further out, Division is one of the busier commercial streets of disadvantaged East Portland, though still very suburban in style as everything out there is.  (For an amusing mayoral comment on that segment, see here.)

Because dense, road-dieted Division is very slow close to the city but wide and busy further out, the project began out with the idea of using Powell close-in and then transitioning to Division further out, as Division got wider, though of course this missed the densest part of Division, which is closest-in.

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However, very little of the corridor would be separated from traffic. While this project was never conceived as rail-replicating, it was based on the premise that a limited-stop service using higher-capacity vehicles, aided by careful signal and queue jump interventions, could effect a meaningful travel time savings along the corridor, compared to trips made today on TriMet’s frequent 4-Division.  That line runs the entire length of Division and is one of the agency’s most productive lines, but it struggles with speed and reliability.

As it turned out, though, the travel time analyses showed that from outer Division to downtown, the circuitous routing via Powell cancelled out any travel time savings from faster operations or more widely spaced stops.

As a result, planners looked at a new approach, one that would seek to improve travel times by using inner Division, which had previously been ruled out. Inner Division is a tightly constrained, 2-lane roadway through one of the most spectacularly densifying corridors in Portland, and one that is rapidly becoming a prime regional dining and entertainment destination. This development has led to predictable local handwringing about parking and travel options. Here’s what that alternative looks like:

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Proposed Division station locations

 

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Current 4-Division eastbound stops

The new plan is basically just stop consolidation with some aesthetic and fare collection/boarding improvements. But the stop consolidation would be dramatic.  Note that one numbered avenue in Portland represents about 300 feet of distance, so the new spacing opens up gaps of up to 2400 feet.  If you’re at 30th, for example, you’d be almost 1/4 mile from the nearest stop.

Such a plan would be controversial but quite also historic.  It’s a very wide spacing for the sole service on a street.  On the other hand, the wide spacing occurs on a street that is very, very walkable — one of the city’s most successful “mainstreets” in fact.  And it’s basically the only way to optimize both speed and frequency on a two-lane mainstreet like inner Division.

At this point, it would be strange to call this project “BRT” (Bus Rapid Transit); even the project webpage refers to this alternative as “Division rapid bus”.

Disappointing as this will be to those who think BRT should emulate rail, it has one huge advantage over light rail.  In Portland, surface light rail tends to get built where there’s room instead of where existing neighborhoods are, so it routinely ends up in ravines next to freeways, a long walk from anything.  This Division project now looks like the answer to a more interesting question:  What is the fastest, most reliable, most attractive service that can penetrate our densest neighborhoods, bringing great transit to the heart of where it’s most needed?

This is such a good question that we shouldn’t let arguments about the definition of “BRT” distract from it.  Because it’s not a question about technology.  It’s a question about people.

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Line 72 stopping pattern (Powell to Division, approx. 0.5 mi)

Upgrading the 4-Division to a rapid bus line (without underlying local service, which is impossible due to the constrained roadway) should present a real improvement in quality of service (in terms of capacity using the larger vehicles, and in a 20-25% travel time savings), while at the same time being easier to implement and less disruptive to existing travel patterns.

It also provides a template for TriMet to consider stop consolidation and frequent rapid service on other corridors like the aforementioned Line 72. Rather than seeing this as a failure to design a rapid transit project, perhaps we can celebrate a process that has steered away from a path that would have resulted in a disappointing outcome, towards a more limited, more economical, but still meaningful improvement for riders.

Does the History of a Technology Matter?

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Mater Hill busway station, Brisbane

Ben Ross has a nice long read in Dissent about the history of Bus Rapid Transit, noting all the ways it’s succeeded, failed, and been co-opted by various non-transit agendas.  He’s especially interested in the way various petroleum-and-asphalt interest groups have supported BRT as an alternative to rail for reasons that probably don’t have much to do with their love of great public transit.  All this is worth reading and knowing about.

But what, exactly, should we do with this history?  Practically everything that breaks through into the public discourse has private public relations money behind it, and that money always has different goals than you and your city do.  That’s why you should always lean into the wind when reading tech media.  But just as it’s wrong to fall for everything you read in corporate press releases, it’s also wrong to reflexively fall against them.  (Cynicism, remember, is consent.)

Galileo paid the bills, in part, by helping the military aim cannonballs correctly.  Does that mean pacifists should resist his insight that Jupiter has moons?

So while I loved Ross’s tour of the history, I reject his dismissive conclusion:

Buses will always be an essential part of public transit. Upgrading them serves urbanism, the environment, and social equity. But a better bus is not a train, and bus rapid transit promoters lead astray when they pretend otherwise. At its worst, BRT can be a Trojan horse for highway building. Even at its best, it is a technocratic solution to a fundamentally political problem.

The term technocratic is really loaded here.  Given the new “revolt against experts” trend in our politics, we urgently need to recognize  hard-earned expertise and to distinguish it from elite selfishness, but technocrat is a slur designed to confuse the two.

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RBWH busway station, Brisbane

There are some great bus rapid transit systems out there, and not just in the developing world.  The mixed motives that underlie BRT advocacy don’t tell us anything about where BRT makes sense, any more than the mixed motives behind rail advocacy do.

A light reading of history can help you recognize the prejudices that may lay behind advocacy on all sides.  But then you have to set that aside, and think for yourself.

 

the explosive global growth of bus rapid transit (BRT)

recent study from ITDP  surveys the growth of BRT around the world over the past decade.  

BRT Infographic

 

Note that IDTP thinks of BRT as something that matches the performance of rail using buses.   ITDP's BRT standard excludes many of the projects that the US Federal Transit Administration calls BRT, which amount to premium buses in mixed traffic with minimal speed and reliability features.*  

China has created the largest quantity of true BRT systems, but of course in per capita terms it's Latin America that is building true BRT most intensively.  Fast-developing middle-wealth countries like China, India, Mexico, and Brazil are the sweet spot for BRT because (a) car ownership is still moderate, (b) government power tends to be consolidated enough that decision making is easy, (c) there is simply not enough money to build massive rail transit systems, at least not quickly and at the necessary scale.  

This news is also interesting in light of the forthcoming Rio de Janeiro conference on climate change, and the rumours that China may be ready to commit to reducing emissions, putting pressure on India to do the same.  Latin America, where many countries of similar wealth already have relatively strong climate change policies, is the perfect site for this conversation.

The other interesting stat is how rapidly the BRT revolution has moved.  Of all the true BRT in the world, 75%  was built in the last decade, mostly in middle-income countries, and the pace shows no signs of abating.

Fortunately, those middle income countries amount to a big share of the world, which could mean a real impact on global transportation impacts over time.

 

* (I tend to agree with ITDP's concern that the overly weak use of the term BRT is making it hard to talk about the original point of the BRT idea, which was to mimic what rail rapid transit does in terms of speed, frequency, and reliability.  This meaning is inherent in the "R" in BRT, which means "rapid".)

silicon valley: bus rapid transit that’s faster than driving?

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El Camino Real BRT Alignment

 

Silicon Valley is easily viewed as a  car-oriented place, where tech giants rule from business parks that are so transit-unfriendly that they have had to run their own bus systems to bring employees from afar.  But one interesting transit project is moving forward: the El Camino BRT, a proposed  rapid transit line connecting Palo Alto and central San Jose. 

El Camino Real ("the Royal Road") is a path defined by Spanish missionaries as they spread north through California. It lies close to the old railroad line now used by Caltrain, and the two facilities combined  determined the locations of the pre-war transit-oriented downtowns that still form the most walkable nodes in the area.  

Today El Camino is the spinal arterial of the San Francisco peninsula, passing through or near most of the downtowns.   This spine continues across Silicon Valley, through Palo Alto, Mountain View, Sunnyvale, Santa Clara and finally downtown San Jose.   (The BRT will not extend the full length of the peninsula, because it is a Santa Clara County project and the county ends at Palo Alto.  However, successful projects do get extended sometimes.)   In Silicon Valley, too, the corridor is far enough from Caltrain that they are not competing.  Caltrain will always be faster but probably less frequent than the BRT, optimized as it is for much longer trips including to San Francisco.

In land use terms, the project corridor is ideal territory for transit – lots of employment and commercial destinations, with strong anchoring institutions at each end.   But while the path is historic, the modern street was designed with a singular focus on auto travel time, as a six-lane divided boulevard. Auto and transit travel times continue to increase substantially as more people come to live and work in the corridor, and even more population and employment growth is forecast for the coming decades.  

Santa Clara VTA and the FTA released the Draft Environmental Impact Report for this project last week, detailing multiple alternatives relating to the extent of dedicated lanes and street configurations. The purpose and need statement tidily summarizes the rationale for this investment:

El Camino Real is an important arterial in Santa Clara County and on the San Francisco Peninsula. However, El Camino Real is predominantly auto-oriented, and streetscape amenities are limited. There are widespread concerns regarding congestion, appearance, and safety, and a general public perception exists that the corridor is not well planned. Exacerbating current conditions, Santa Clara County is expected to experience substantial growth in the next 30 years from 2010 to 2040. If no improvements are implemented, heavy demand will potentially be placed on the existing transportation infrastructure, which is planned to increase by only 5 to 6 percent. 

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This striking graph (which I couldn't locate in the report itself, but which is reproduced over at the TransForum blog), compares transit travel time among the four alternatives:

In the A4c alternative (the alternative with the greatest extent of exclusive lanes), a trip during the peak through the corridor would actually be faster on transit than driving, and dramatically faster than the same trip today.

The various alternatives' alignments are compared below:

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As usual with arterial BRT in the US, there will be some mixed-traffic segments, and the line will only be as realiable as its least reliable point.  Note that the alternatives seem to envision different responses to city limits, as though anticipating that as you get further west (which means wealthier, but also closer to big destinations like Palo Alto and Stanford University), support for exclusive lanes will decline.  It will be interesting to see if this is true, in a very educated polity, when the benefits are understood.  

quote of the week: “rail is only part of the equation”

 

Trains would be just one layer of a comprehensive, multi-modal network that greatly enhances both neighborhood and regional accessibility for people all across the [Los Angeles] region. …

A singular focus on rail would divide the region into two: neighborhoods with rail and neighborhoods without. Such a future would perpetuate income inequality as housing costs rise near stations and station areas would be choked with traffic congestion. …

Getting our existing buses out of traffic is the quickest, most cost-effective means to bring high-quality transit to the greatest number of Angelenos.

Juan Matute, UCLA Institute of Transportation Studies
from a discussion called "Trains are Not the Silver Bullet"
 at ZocaloPublicSquare

This is from a collection of commentary about the the role of rail in the larger context of transit investment strategies.  Read the whole thing!

 

 

 

 

 

quote of the week: the neglected american bus

In the six cases examined, we conducted off the record interviews with public officials, general managers, and thought leaders in each region. One of the consistent themes that emerged was that the bus systems and bus passengers were an afterthought. In every region – Chicago, New York, Boston, Minneapolis/St. Paul, Dallas/Ft. Worth, and the Bay Area – rail was the primary focus of virtually everyone we interviewed. We also found that maps of the regional transit networks tellingly either included a jumbled mess of bus routes behind a clean rail network, or ignored bus altogether.

It is likely this bias toward rail has very little to do with governance. But it does have a negative impact on transit delivery, particularly from a customer point of view. The vast majority of transit riders in the United States are on buses, so it would make sense to devote more resources and attention to them compared to rail riders, rather than less. Also, improvements to the bus network are likely to be less expensive than new rail expansions, and would be likely to yield substantially more net benefit per dollar. Yet while every region we visited had a new rail expansion either in planning or under construction, outside of New York none of the regions had any plans for regional bus networks, reorganization of existing bus systems, or major expansions of bus rapid transit (BRT).

Joshua Schank, President CEO,
Eno Center for Transportation
"The Case of the Neglected Bus"

I've certainly noticed, in my own work, that the aggressive, agency-wide commitment to building a complete access-maximizing transit system is stronger in cities that don't have much rail, or where rail is in early stages of development, as in Houston.  Key tools for total network legibility, such as Frequent Network branding, also seem to be spreading much more effectively in the midsized transit authorities than in the gigantic ones.

A while back I had a brief chat with a major airline CEO at an event.  He asked me: "So what's the future of transit.  It's rail, isn't it?"  I wanted to say: "So what's the future of aviation?  It's all intercontinental jumbo jets, isn't it?  

Or is it about people feeling free to go places?  In that case, the future of aviation is a network, where many types of vehicle have an essential role.  

Does transit infrastructure cause ridership?

Does building a new transit line trigger ridership?  Does it even make sense to talk about the ridership of a piece of transit infrastructure?  

If you say yes, you're expressing an infrastructurist world-view that is common in transit investment discussions.  The right answer to the above questions, of course, is "No, but:

  • Infrastructure permits the operation of some kind of useful transit service, which consists of vehicles running with a certain speed, frequency, reliabilty, civility and a few other variables.
  • That service triggers ridership."

To the infrastructurist, this little term — "service" — is a mere pebble in a great torrent of causation that flows from infrastructure to ridership.  By contrast, service planners, and most transit riders that I've ever met, insist that service is the whole point of the infrastructure.

If you read the literature of infrastructure analysis, you  encounter the infrastructurist world view all the time, mostly in ways that's unconscious on the authors' part but still a source of confusion.  This afternoon I was browsing TCRP 167, "Making Effective Fixed-Guideway Transit Investments: Indicators of Success", which includes some really useful explorations of land use factors affecting the success of transit lines.  But when they talked about infrastructure features as causes of ridership, the report routinely delivered weirdness like this:

The percentage of the project’s alignment that is at grade proved to be a negative indicator of project-level ridership. At-grade projects may be more prevalent in places that are lower in density, while transit is more likely to be grade-separated in places with higher density or land value. Thus, this indicator may be reflective of density. It may also be true that at-grade systems are slower than grade-separated systems. At-grade status may reflect a bundle of operational characteristics such as speed, frequency, and reliability, although the analysis did not find that these factors individually had a statistically significant effect on ridership.  [TCRP 167, 1-17]

This careful talk about how a correlation "may" reflect density or "operational features" sounds vague and speculative when it's actually very easy to establish.  There is no shortage of evidence that:

  • High density reliably triggers ridership.
  • Areas of high density are less likely to have available surface rights of way.
  • Therefore, highest ridership segments tend to be grade-separated.

So this is a case where "A correlates with B" does not mean "A causes B" or "B causes A".  It means "A and B are both results of common cause C".  It's important to know that, because it means you won't get B simply by doing A, which is the way that claims of correlation are usually misunderstood by the media and general public.

Later in the paragraph, the authors again describe the obvious as a mystery:

At grade status may reflect a bundle of operational characteristics such as speed, frequency, and reliability …  

Yes, it certainly may, but rather than lumping all the at-grade rail projects together, they could have observed whether each one actually does.  

… although the analysis did not find that these factors [speed, frequency, and reliability] individually had a statistically significant effect on ridership

While this dataset of new infrastructure projects is too small and noisy to capture the relationship of speed, frequency, and reliability to ridership, the vastly larger dataset of the experience of  transit service knows these factors to be overwhelming.  What's more, we can describe the mechanism of the relationship, instead of just observing correlations:  Speed, frequency, and reliability are the main measures of whether you reach your destination on time.  Given this, the burden of proof should certainly be on those who suggest that ridership is possibly unrelated to whether a service is useful for that purpose.

Note the word choice:  To the infrastructurist, speed, frequency and reliability are dismissed as operational, whereas I would call them fundamental.   To the transit customer who wants to get where she's going, these "operational" variables are the ones that determine whether, or when, she'll get there.  It doesn't matter whether the line is at-grade or underground; it matters whether the service achieves a certain speed and reliability, and those design features are one small element in what determines that.  

I deliberately chose a TCRP example because the authors of specific passages are not identified, and I have no interest in picking on any particular author.  Rather, my point is that infrastructurism so pervasive; I hear it all the time in discussions of transit projects.  

I wonder, also, if infrastructurism is a motorist's error: In the world of roads, the infrastructure really is the cause of most of the outcomes; if you come from that world it's easy to miss how profoundly different transit is in this respect, and how different the mode of analysis must be to address transit fairly.

Whenever you hear someone talk about the ridership of a piece of infrastructure, remember: Transit infrastructure can't get people to their destinations.  Only transit service can.  So study the service, not just the infrastructure!