Human Transit

by Jarrett Walker

Plumber’s Questions

The role of the expert is to ask the questions that clarify the community’s values and expectations. It’s important for the expert not to impart too many of their own opinions on the situation in place of the community’s.

The process is a conversation, and in a productive conversation that leads to consensus, nobody cares who made the first move.

Too often, we defer to a small group of intensely interested people (such as developers, activists, neighborhood groups, labor unions, and purveyors of transit technology) because the debate seems too technical for most of us to follow.

Walker calls these Plumber’s Questions: questions that focus on common and important trade-offs so that the client can figure out their priorities.

“I can fix it up for now for $50, and it’ll work for a year or so. Or, if I replace the whole whatsit assembly and connect it with a new doohickey, it’ll be just like new, but that would be about $700 and it would take a week for the part to get here from Malaysia.”

Throughout this book, I will be like your plumber, asking, “Do you want more of this or more of that? You have to choose.”

In fact, every one of these choices defines a spectrum. You can come down at any point between the two extremes

Experts do have their own opinions about Plumber’s Questions - Walker prefers to reduce network complexity by reducing connections. Responses to these clarifying questions lie on a spectrum - people normally bucket potential responses for simplicity, compared to the nuance of a spectrum.

Sometimes, we’re tempted to think about a spectrum as though it were a series of box-like categories.

If you already know where you are on a question, it can feel threatening for me to point out that there is a spectrum of credible opinions and that there are other possible valid positions on that spectrum.

What is Transit?

At its core, transit is about multiple people riding in one vehicle even though they are not intentionally traveling together or even going to the same places. The core challenge of transit design, then, is how to run vehicles so that people with different origins, destinations, and purposes can make their trip at the same time and will be motivated to choose transit to do so.

Our travel isn’t motivated by a sheer desire for movement; it’s motivated by the need to do something—to make some kind of economic or personal contact—that is too far away to walk to. In most cases, we don’t want movement. We want access.

Mobility doesn’t always generate movement, but it does generate happiness. For this reason, people will resist locating in places where it seems to be denied.

Seven Demands of Transit

  1. It takes me where I want to go
  2. It takes me when I want to go
  3. It is a good use of my time
  4. It is a good use of my money
  5. It respects me in the level of safety, comfort and amenity it provides
  6. I can trust it
  7. It gives me freedom to change my plans

Seven Phases of a Trip

  1. Understanding the options
  2. Accessing the origin
  3. Waiting for arrival
  4. Payment upon boarding
  5. Riding the transit
  6. Connecting (repeat 2-5)
  7. Accessing the destination

Transit extends walking range

The key KPI of transit is extending mobility - allowing people to easily “walk” from one place to another with the aid of transit in between.

Public transit delivers people from one part of the city to another as pedestrians, eliminating all the challenges of storing a personal vehicle.

The core product that arises from transit is personal mobility, by which I mean the freedom to move beyond your walking range.

If you want to encourage pedestrian life, you need to connect pedestrian-intensive places to one another in a way that the pedestrian can use.

Transit Agencies

Transit agencies have two opposing maximisation goals:

  1. Coverage (i.e. serve everyone)
  2. Efficiency (passenger kms / $)

Equity begets complexity. The more precisely equitable a fare system tries to be, the more complicated it becomes. Any transit agency that is unprepared to implement “perfectly equitable” fares … must accept being accused of inequity as an inevitable consequence of whatever decision it makes.

Expectations

Expectations about transit services impact most of the 7 demands of transit (at least where, when, time, trust, and freedom) - managing and matching customers’ expectations is an important part of service delivery.

Transit planners hate deviations, because passengers riding through on the line hate them too. Deviations are more irritating than circuitous routes because they feel like broken promises.

So the word route lowers expectations for the frequency and reliability of a service. The word line raises those expectations.

In cities that already offer real-time information about the actual location of a bus or railcar, my walk to the stop is more pleasant because I’m not anxious about whether I might miss it.

Sudden “bright ideas,” such as building a transit line in an unexpected place, can be bad ideas for the region even if they are good ideas in the abstract, if their side effect is to make everyone uncertain about what, if anything, is going to get built in the future.

Frequency is freedom

Frequency is the single most important variable in meeting our mobility desires.

Because transit travel time includes the waiting time imposed by frequency, and to maximize frequency, we need to run the fewest possible route miles of rapid transit service. The more distance we need our lines to cover, the less frequently we can afford to run them.

Reliability and average speed are different concepts, but both are undermined by the same kinds of delay, and when we reduce delay, service usually runs both faster and more reliably.

The unglamorous work of stop spacing is so important to get right

City Structure

City structure is the biggest influence on transit outcomes.

On busy streets, an advantage of putting transit lanes in the center, rather than on the side, is that it eliminates most friction.

High-quality and cost-effective transit implies certain geometric patterns. To the extent that those patterns work with the design of your community, you can have transit that’s both high-quality and cost-effective. To the extent that they don’t, you can’t.

The physical design of cities determines transit outcomes far more than transit planning does.

On any great urban street, every part of the current use has its fierce defenders. Local merchants will do anything to keep the on-street parking in front of their businesses. Motorists will worry (not always correctly) that losing a lane of traffic means more congestion. Removing landscaping can be controversial, especially if mature trees are involved.

Once you decide that your streets are designed for people movement rather than vehicle movement, turning car lanes into transit lanes not only is fair but is also the most effective way to maximize the total number of people who can move along the street.

Many great urban design ideas can follow from accepting the needs of connecting transit services into the structure of an urban center.

What matters is not the average density but the percentage of the population living at higher densities.

Chokepoints—like mountain passes and water barriers of many cities—offer transit a potential advantage.

The shape of a chokepoint requires parallel lines to converge to pass through it. This creates opportunities for people to connect among these lines, thus reaching more possible destinations.

Urban Design

Therefore, when structuring the city (through urban design), it’s best to consider the impact / outcome of transport decisions.

One of the most urgent needs related to transit is to help people make smarter decisions about where to locate their homes and businesses, depending on the level of transit mobility that matters to them.

The high-quality transit in Denseville—especially if it’s readily visible via tools like a Frequent Network map—can make more people want to locate there. If your city’s politicians and developers allow that to happen, Denseville will get even denser. Now you have a feedback loop, because density, service, and ridership are all feeding off of one another, each growing because the other two are growing. That path can lead to denser and also much more sustainable cities, where transit plays a huge role in mobility while walking and cycling, supplemented by carsharing, do much of the rest.

Mapping

A more bewildering map and information system that can discourage people exploring the service for the first time.

Most transit maps show the paths that transit runs on but not how frequently it runs. As a result, they tend to conceal the patterns of good service, which tend also to be the patterns of good ridership.

So, a transit map that makes all lines look equal is like a road map that doesn’t show the difference between a freeway and a gravel road.

Motorist’s perception

People’s most common transit experience is through private transport, as motorists - making transit decisions from a motorist’s perspective can lead to the wrong solutions.

In most cities, the motorist’s perception is so dominant that their confusions can become political imperatives.

But for transit, the vehicle speed is a small part of the picture. What matters is how much time it takes to complete an entire desired trip.

Transit has to exist when you need it (span), and it needs to be coming soon (frequency). Otherwise, waiting time will wipe out any time savings from a faster service.

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