The 30-Minute City: Designing for (Open) Access

I am pleased to announce that you can now download a PDF version of The 30-Minute City: Designing for Access from the University of Sydney eScholarship Repository. (Free). You are of course welcome to purchase a bound or electronic copy as well.

The 30-Minute City by David M. Levinson
The 30-Minute City: Designing for Access by David M. Levinson
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Book (PDF, 170.38MB)

Date

2019-12

Author

Levinson, David M.

Description

This book describes how to implement The 30-Minute City. The first part of the book explains accessibility. We next consider access through history (chapter 2). Access is the driving force behind how cities were built. Its use today is described when looking at access and the Greater Sydney Commission’s plan for Sydney. We then examine short-run fixes: things that can be done instantaneously, or nearly so, at low budget to restore access for people, which include retiming traffic signals (chapter 3) and deploying bike sharing (chapter 5) supported by protected bike lane networks (chapter 4), as well public transport timetables (chapter 6). We explore medium-run fixes that include implementing rapid bus networks (chapter 7) and configuring how people get to train stations by foot and on bus (chapter 8). We turn to longer-run fixes. These are as much policy changes as large investments, and include job/worker balance (chapter 10) and network restructuring (chapter 9) as well as urban restoration (chapter 11), suburban retrofit (chapter 12), and greenfield development (chapter 13). We conclude with thoughts about the ‘pointlessness’ of cities and how to restructure practice (chapter 14). The appendices provide detail on access measurement (Appendix A), the idea of accessibility loss (B), valuation (C), the rationale for the 30-minute threshold (D), and reliability (E). It concludes with what should we research (F).

URI

https://ses.library.usyd.edu.au/handle/2123/21630

On the word “Access”

Language is an evolving thing. The word “access” (and the related “accessibility”) for instance has many meanings outside the domain of transport. For instance, when we talk about “Access to voting” in the US (the only so-called democracy where this is so much of a problem) is only in part about physically traveling to the polling place, much of it is about enfranchisement and rights.

etymology-access-110p_l
Access: Etymology Online

The Online Etymology Dictionary writes:

accessible (adj.)

c. 1400, “affording access, capable of being approached or reached,” from Middle French accessible, from Late Latin accessibilis, verbal adjective from Latin accessus “a coming near, an approach; an entrance,” from accedere “approach, go to, come near, enter upon” (see accede). Meaning “easy to reach” is from 1640s; of art or writing, “able to be readily understood,” 1961 (a word not needed before writing or art often deliberately was made not so). Related: Accessibility.
accessibility (n.)
1758, from French accessibilité (from Late Latin accessibilitas), or else a native formation from accessible + -ity.

access (n.)

early 14c., “an attack of fever,” from Old French acces “onslaught, attack; onset (of an illness)” (14c.), from Latin accessus “a coming to, an approach; way of approach, entrance,” noun use of past participle of accedere “to approach,” from assimilated form of ad “to” (see ad-) + cedere “go, move, withdraw” (from PIE root *ked- “to go, yield”). English sense of “an entrance” (c. 1600) is directly from Latin. Meaning “habit or power of getting into the presence of (someone or something)” is from late 14c.

access (v.)

1962, originally in computing, from access (n.). Related: Accessed; accessing.

The word early on (1758) had connotations well-beyond transport, including illness and sex (e.g. “her husband was away in France, and had no opportunity to engage in access, therefore he is not the father.”).

Access as a verb derives in English from 1962 apparently, in computing (as in “she accessed the database to study the relationship between jobs and housing.”). Obviously we have used it in a back-formation in the sense of “to access destinations”, harkening back to its original Latin roots. So the original Latin verb was nounified in French. The subsequent English noun from the Latin was later verbified.

But we should remember that the words themselves are entirely transport derived, and have a long and primary history associated with physical movement and ability to reach.

That means we in the transport community should not shy away from using them to mean what they meant when we first started using them, so long as we are not ambiguous about what we mean. We should not be word-shamed.

 

Multi-Activity Access: How Activity Choice Affects Opportunity

Recently published:

It is commonly seen that accessibility is measured considering only one opportunity or activity type or purpose of interest, e.g., jobs. The value of a location, and thus the overall access, however, depends on the ability to reach many different types of opportunities. This paper clarifies the concept of multi-activity accessibility, which combines multiple types of opportunities into a single aggregated access measure, and aims to find more comprehensive answers for the questions: what is being accessed, by what extent, and how it varies by employment status and by gender. The Minneapolis – St. Paul metropolitan region is selected for the measurement of multi-activity accessibility, using both primal and dual measures of cumulative access, for auto and transit. It is hypothesized that workers and non-workers, and males and females have different accessibility profiles. This research demonstrates its practicality at the scale of a metropolitan area, and highlights the differences in access for workers and non-workers, and men and women, because of differences in their activity participation.

multi-access-method-frame
Multi-Activity Accessibility Framework

 

Accessibility and the Pursuit of Happiness

As I have argued elsewhere [Towards A General Theory of Access]:

The only reason to locate anywhere is to be near some people, places, and things, be far from others, and possess still others. Since being far from something is really just being near the absence of that thing, and pos-session is just the ability to have something (and legally prohibit someone else from having it), we can see that location is about proximity. People make location decisions all the time, from whether to move from North America to Australia, to traveling to the mall by car or bus, to standing near a person at a reception, or even sitting on the chair or the couch.

Cities and their networks exist to easily connect people with each other. We measure that ability in terms of accessibility. The more accessibility, the more opportunity. Opportunity gives choices, and better choices make for happiness (too many choices may paradoxically reduce happiness, but surely that is a problem we would prefer to have than too few.) In short cities and networks allow the pursuit of happiness. So accessibility is about freedom: the freedom to pursue happiness.

But this freedom is limited by at least three types of constraints (Hägerstrand, 1970). Extending an earlier discussion:

  • Capability constraints refer to biological (e.g., sleeping and eating) and physical (e.g., vehicle ownership, time availability, maximum speed of travel, ability to afford) limitations that restrict an individual from participating in activities. In our case network speed and directness affects travel times, and the spatial distribution of activities affects participation. Dependence on public transport restricts travel to the schedule of the service. The less frequent the service, the less freedom one has, as argued by Jarrett Walker in Frequency is Freedom.
  • Authority constraints represent limitations to accessing particular areas (e.g., military bases) or individuals that are classified by certain people or institutions. Legal barriers to travel, regulations on speed, rules about what vehicles can be in which spaces are all authority constraints.
  • Coupling constraints indicate limitations for two or more individuals to participate in an activity in the same location at the same time interval. There may also be social and familial obligations that limit the ability to pursue other activities.

These are not fully independent. Policies about the allocation of road space, which may give more space over to automobiles than bicycles than warranted is a combination of authority constraint and capability constraint.

So because the value of cities emerges from freedom and access, the limits to freedom and access limit value. While some of those limits are unavoidable, others, like authority constraints, can be determined by policy.

Staying in my lane, transport in cities have a number of problems. The following is a non-exclusive, unranked list. These are all problems associated with access in one form or another.

  1. Pedestrian and bicyclist conditions, particularly safety from vehicles, are worse in many ways than a century ago. My ability to move on foot (and thus access destinations) is restricted by traffic signals and the danger of moving cars.
  2. Violence, and more significantly fear of violence, especially state-sanctioned violence, discourages people subject to such violence from taking advantage of access that is already there. If there are places you cannot go without risking life and limb, you will avoid them, reducing your access and freedom.
  3. Job/housing imbalance exists and may get worse as cities get larger. Longer commute distances (and thus times) reduce access and opportunity. Many cities have regulations that limit housing in job-rich areas. The City of Sydney is no exception. This necessarily increases commute times.
  4. Failure to efficiently price parking and roads leads to overuse. Roads are congested and transport is underfunded. If only there were mechanisms to reduce overuse while raising revenue. On-street parking reduces capacity for movement (car, bike and bus lanes), reducing the speed, and thus access by those modes, while benefitting very few who need to walk a shorter distance to their final destination.
  5. Transport externalities (road hazard, noise, pollution) are underpriced, and thus overproduced. This increases the social cost of access. They are ignored in most analyses of traffic, and so spending is misallocated.
  6. Walled and fenced schools, lack of integration between schools, playgrounds, and libraries make things that should and could be accessible with a modicum of management inaccessible much of the time.
  7. Housing affordability, quality, and supply directly relate to how easily new housing can be reached. Lack of housing reduces accessibility.
  8. Poor design and aesthetics makes places unpleasant and reduces the valuation people put on those places. Effective accessibility drops.
  9. Concurrency between infrastructure and development is hard to achieve in growing areas. Lack of infrastructure increases travel costs (and reduces access) for existing residents as well as new. Access creates value but that value is not captured to fund access.
  10. Overspending on capital and underspending on maintenance means that transport facilities built a long time ago fail more quickly and become unavailable, reducing access. Existing facilities are almost always more important than new facilities, because the demand (and access) provided are certain, because they have become part of the landscape, and so decades of decisions have been made assuming their existence.

The right to pursue happiness is a fundamental value in the United States, right there in the founding document, the Declaration of Independence. It depends entirely on the ability to move in order to reach people, places, and things that might provide happiness. That is, in modern terms, access.

The problems enumerated above are all solvable, like so many other problems in modern society, and yet remain unsolved in many places. Without much technical difficulty we could expand effective access for people on foot, on bike, or on public transport, and even those in cars. Transport access problems may seem prosaic compared to the core issues of environmental disaster, economic exuberance, or the risk to democracy. But these problems relate directly. Transport produces pollution, more than it should because the pollution is unpriced. Transport spending is inefficient, stretching the economy. The problems of democracy are in many ways problems of access as well, not just access to polling places (though that is worsening), but access to the decision process, and access to information.

Queen Victoria Buidling, George Street, Sydney.
Queen Victoria Buidling, George Street, Sydney.

Towards a general theory of access

Recently published

Abstract: This paper integrates and extends many of the concepts of accessibility deriving from Hansen’s (1959) seminal paper, and develops a theory of access that generalizes from the particular measures of access that have become increasingly common. Access is now measured for a particular place by a particular mode for a particular purpose at a particular time in a particular year. General access is derived as a theoretical ideal that would be measured for all places, all modes, all purposes, at all times, over the lifecycle of a project. It is posited that more general access measures better explain spatial location phenomena.

Transportist: May 2020

Welcome to the latest issue of The Transportist, especially to our new readers. As always you can follow along at the  transportist.org or on Twitter Covid-19 retains its top spot in the armageddon-of-the-month rankings for three months running, after surpassing fires, and overtaking Middle East war.

Open Access Access Redux

  • We are pleased to announce that you can now download a PDF version of A Political Economy of Access: Infrastructure, Networks, Cities, and Institutions from the University of Sydney eScholarship Repository. (Free)

    A Political Economy of Access: Infrastructure, Networks, Cities, and Institutions

    A Political Economy of Access: Infrastructure, Networks, Cities, and Institutions by David M. Levinson and David A. KingWhy should you read another book about transport and land use? This book differs in that we won’t focus on empirical arguments – we present political arguments. We argue the political aspects of transport policy shouldn’t be assumed away or treated as a nuisance. Political choices are the core reasons our cities look and function the way they do. There is no original sin that we can undo that will lead to utopian visions of urban life. The book begins by introducing and expanding on the idea of Accessibility. Then we proceed through several major parts: Infrastructure Preservation, Network Expansion, Cities, and Institutions. Infrastructure preservation concerns the relatively short-run issues of how to maintain and operate the existing surface transport system (roads and transit). Network expansion in contrast is a long-run problem, how to enlarge the network, or rather, why enlarging the network is now so difficult. Cities examines how we organize, regulate, and expand our cities to address the failures of transport policy, and falls into the time-frame of the very long-run, as property rights and land uses are often stickier than the concrete of the network is durable. In the part on Institutions we consider things that might at first blush appear to be short-run and malleable, are in fact very long-run. Institutions seem to outlast the infrastructure they manage. Many of the transport and land use problems we want to solve already have technical solutions. What these problems don’t have, and what we hope to contribute, are political solutions. We expect the audience for this book to be practitioners, planners, engineers, advocates, urbanists, students of transport, and fellow academics.

    URI

    https://ses.library.usyd.edu.au/handle/2123/21629

    [That’s right, we made A Political Economy of Access a free download. Get your copy now. Read it. Make your students and friends and colleagues read it. No excuses. You have the time.]

Conferences

  • Bridging Transport Research – will be (and always has been) run entirely online. While original aimed at researchers from countries who could not travel for economic or political reasons to the Transportation Research Board Annual Meeting, that is now a much broader category of people, and will be held in August 2020. Papers are due May 15.

In happier matters, I am thinking about a Reviewers Guild to help break academics from their subservience to the for-profit journal publishing hegemony. An editable Google Doc is available to read at the link. Let me know if you are interested in participating.

Transportist Blog

Transport Findings

WalkSydney

News & Opinion

Interesting Research (by others)

Books

A Political Economy of Access – Open Access

We are pleased to announce that you can now download a PDF version of A Political Economy of Access: Infrastructure, Networks, Cities, and Institutions from the University of Sydney eScholarship Repository. (Free)

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A Political Economy of Access: Infrastructure, Networks, Cities, and Institutions by David M. Levinson and David A. King
A Political Economy of Access: Infrastructure, Networks, Cities, and Institutions by David M. Levinson and David A. King

book (PDF, 79.23MB)
Date
2019-03

Author

  • Levinson, David M.
  • King, David A.

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Why should you read another book about transport and land use? This book differs in that we won’t focus on empirical arguments – we present political arguments. We argue the political aspects of transport policy shouldn’t be assumed away or treated as a nuisance. Political choices are the core reasons our cities look and function the way they do. There is no original sin that we can undo that will lead to utopian visions of urban life. The book begins by introducing and expanding on the idea of Accessibility. Then we proceed through several major parts: Infrastructure Preservation, Network Expansion, Cities, and Institutions. Infrastructure preservation concerns the relatively short-run issues of how to maintain and operate the existing surface transport system (roads and transit). Network expansion in contrast is a long-run problem, how to enlarge the network, or rather, why enlarging the network is now so difficult. Cities examines how we organize, regulate, and expand our cities to address the failures of transport policy, and falls into the time-frame of the very long-run, as property rights and land uses are often stickier than the concrete of the network is durable. In the part on Institutions we consider things that might at first blush appear to be short-run and malleable, are in fact very long-run. Institutions seem to outlast the infrastructure they manage. Many of the transport and land use problems we want to solve already have technical solutions. What these problems don’t have, and what we hope to contribute, are political solutions. We expect the audience for this book to be practitioners, planners, engineers, advocates, urbanists, students of transport, and fellow academics.

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The 30-Minute City: A Review

Tom van Vuren reviewed my recent book, the The 30-Minute City in Transport Reviews. I abstract some of it here.

cropped-30-minute-city-cover-r1-front.jpg
The 30-Minute City: Designing for Access

The author describes the book as a fast read. He is right – it is written in a very straight-forward style, avoids jargon and as such, I think it would be enjoyed by practitioners, first-degree students and even those with just a general interest in transport planning and accessibility. This is the fifth book published by Network Design Lab in David Levinson’s Access series.

Much of the book describes ways in which a 30-minute city may be created; and as Levinson says, “we do not require autonomous vehicles, hyperloops, drones, trackless trams, micromobility, or multi-copters, even if we eventually see such things widely deployed”. After the introductory chapters, chapters 3 to 10 provide practical examples of how accessibility has been eroded and conversely, how it can be improved by interventions that can be copied from elsewhere.

I was particularly taken by Chapter 3 on Traffic Signals. Through a simple example, Levinson illustrates that in a typical urban environment pedestrians lose 25%–30% of their effective speed because of traffic signals that are coordinated for cars, reducing their accessibility to jobs and other opportunities in a 30-minute walk space by almost half. He also offers solutions that can be implemented immediately. Essential reading for all practising signal engineers!

Another excellent illustration is given in Chapter 8 on Interfaces. The design of a station can have a big impact on accessibility. Through another Sydney example, he explains how saving just 75 seconds entering and leaving a train station can improve accessibility by 8%, for example by increasing the number or relocation of entries and exits, or changing the interfacing with buses.

In his last Chapter Levinson makes a plea for a new profession, Urban Operations – people engaged in improving today’s city, not just planning for tomorrow, but optimising for the system as a whole, using resources on-hand. As he says: “we have enough problems today. We also have solutions available to us today and we don’t implement them”.

Levinson’s arguments around urban restoration and retrofitting deserve a space in all transport planning courses. He makes a strong case to always consider the era during which an urban area evolved when developing solutions to address currently experienced traffic problems. Levinson advocates to restore what worked at that time (such as trams in historic centres of the early twentieth century), but not to try and impose such solutions in locations that were built for the motorcar in the fifties and sixties. The latter can only be retrofitted, at a cost and not necessarily effectively. In terms of retrofitting, Levinson provides a telling example of the temporary land-banking in urban at grade parking lots and concludes wistfully that unfortunately, temporary is often indefinite.

I enjoyed this book for two reasons: As a dyed-in-the-wool, it challenged me to think differently about what transport planning and traffic engineering should really achieve. Secondly, Levinson peppers his text with memorable one-liners and inventive terms: who had heard of gradial before? Two noticeable examples that I might use myself:

  • Gradial, or the unreasonable network – Embedded infrastructure cannot adapt much to the world around it. But if it were optimal for the world in which it was designed, it is unlikely to be optimal as that world changes. The network, designed for a given technology, is very hard to adapt to a different technology. Instead, we expect the world to adapt to the infrastructure. And
  • There are many techniques for making the most popular mode, the automobile, greener. We need to think more about making the greenest modes much more popular.

As would be expected, the book finishes with an extensive and useful bibliography.

Foggy Bottom top D.C. neighborhood for walking accessibility, UMD report finds

Lia DeGroot at the GWU student newspaper wrote Foggy Bottom top D.C. neighborhood for walking accessibility, UMD report finds. The report  was authored by D.W. Rowlands. (This same analysis of course is in the Access Across America reports, without the local focus.)

DC-LenfantTransportation experts said high walkability ratings can encourage residents to walk to nearby locations, which is a healthier and more sustainable alternative to driving cars.

David Levinson, a professor of transport engineering in the School of Civil Engineering at the University of Sydney, said walking accessibility matters when people are choosing where to live. He said the more places that a person can reach in a short period of time, the higher the real estate market is in the area.

“People pay a premium (higher rents and land value) to live in places with high access by walking and public transport to jobs, shops, good schools and other amenities,” Levinson said in an email. “They pay a smaller premium for places with high accessibility by automobile.”

A report released late last year found that home sale prices in Foggy Bottom and the West End had increased by more than 40 percent in 2019.

Levinson added that city officials can time crosswalks to reduce pedestrian wait times and permit “high density developments” to increase walking accessibility in the city.

“Cities with dense street networks help, but the traffic signals also need to be timed so pedestrians don’t have to wait too long to cross the street,” he said. “If it takes two minutes to cross the street, that’s 20 percent of a 10-minute walk, and accessibility is reduced significantly.”

My full response: We prefer to talk about “accessibility”, [than density] how many destinations someone can reach in a given amount of time. So for instance, how many restaurants are within a 10 minute walk, or can you buy a pint-of-milk within 10 minutes of your home. This matters because time is limited, and the more things you can reach in less time, the more options you have, which people usually value (2 supermarkets is better than one both because of more choices and more competition driving down prices). People pay a premium (higher rents and land value) to live in places with high access by walking and public transport to jobs, shops, good schools, and other amenities. They pay a smaller premium for places with high accessibility by automobile. High is relative, so more access is better than less (all else equal). Cities with dense street networks help, but the traffic signals also need to be timed so pedestrians don’t have to wait too long to cross the street, (if it takes 2 minutes to cross the street, that’s 20% of a 10 minute walk, and accessibility is reduced significantly). Government can permit high density development so that there are more opportunities available, and it can improve walking conditions.