Cage the Automobile

Is the purpose of bollards to keep people in or keep cars out? A reader writes:

 

Bollards done wrong, Egypt.
Bollards done wrong. It’s a long pedestrian street, would you bollard the entire street,  because they are proposing low risers. You will end caging the people like in Egypt.

After the attack in Toronto last week with a guy driving a van and killing 10 people and injuring 15, Montreal announced a new plan for Saint Catherine street making it pedestrian friendly, with a nice wide sidewalk showing young people walking, yet  when the mayor was asked if they planned for pedestrian safety from such attack she said ‘no, we did not.’

So the moral question: should we change our planning for pedestrians to ensure safety from a crazy person in a van, terrorists, drunk drivers,  just incapacitated drivers. This is not the first, and will not be the last, time a driver plows down pedestrians. By doing so we show weakness to terrorists? Are we converting the outdoors to a Zoo placing pedestrians in cages. Should the woonerf, for example, be like an open zoo.

It’s a moral and ethical question how much separation should we have in an era when crazy people uses cars as weapons to kill random humans. How many incidents and deaths will it take to change the approach for pedestrian environments to make it as safe as air travel.  If we  add more small obstacles, how much will they spoil the pedestrian environment and sense of freedom.

 

The crazy person in a van problem is only going to get worse with automation and especially connectivity, a remote control car bomb is even easier than a suicide.

This Delft Bollard is a casualty of the Car Wars.

In my view, cars should be in the cages, the people should be free. And then the cages need to be made smaller and smaller.

All urban streets in heavily pedestrian trafficked areas should have bollards or equivalent to keep the cars away from the people. Woonerfs are fine for residential streets, and if people want to encroach on shared space that is also fine, but cars should not encroach on people space. Just as we don’t let cars in most buildings, there should be outdoor public spaces where they are also prohibited.

We don’t need fences or chains like in the photo of Egypt, just lots of posts (trees, bike racks, benches, bus stops, street furniture, planters etc.) that make it impossible for a car to run down the sidewalk or into buildings. This furniture of course should not interfere with the free flowing movement of people, and might require taking lanes from the storage, or even movement, of cars. As with all good urban design, examples of this are in Delft, with some lowerable Bollards to allow service, emergency, and freight vehicles in when needed.

 

Delft defining Pedestrian domain.
Delft, lowerable Bollards on a bridge

 

 

 

 

 

The Ambiguous Hump

How about an ambiguous hump to start your Valentine’s Day ?  Pedestrian / street interfaces in Sydney are needlessly inconsistent. When is a Speed Hump (Speed Table) also a Pedestrian Crossing? When is a Pedestrian Crossing also a Speed Hump? When the traffic engineer felt like it.

Walking about Sydney, we see all sorts of cases. I propose a simpler rule: All high demand pedestrian crossings should be speed humps on the road (the should rise to the sidewalk level). All low demand roadway/sidewalk crossings should be speed humps so that these road and especially  laneway (alley) crossings extend the sidewalk across the road (so the pedestrian is not lowering themself crossing the street, but rather the car is slowing and rising while crossing the sidewalk). I have photos illustrating good, bad, and ambiguous examples from Sydney.

A midblock raised crosswalk/speed hump at the busy entrance to the Broadway Shopping Center. This is excellent, and cars reluctantly yield to the dominant pedestrian. The walk leads to escalators. (Mid-right)
A midblock raised crosswalk/speed hump at the busy entrance to the Broadway Shopping Center. This is excellent, and cars reluctantly yield to the dominant pedestrian. The walk leads to escalators. (Mid-right)
A raised sidewalk across a laneway (alley) at Broadway Shopping Center. This is also excellent, and should be ubiquitous at every laneway in Sydney. The pedestrian is giving me the side eye for taking his picture, but he is important to illustrate traffic safety.
A raised sidewalk across a laneway (alley) at Broadway Shopping Center. This is also excellent, and should be ubiquitous at every laneway in Sydney. The pedestrian is giving me the side eye for taking his picture, but he is important to illustrate traffic safety.
Raised pedestrian crosswalk in Cronulla
Raised pedestrian crosswalk in Cronulla. Similar to the first example at Broadway, but a much less trafficked intersection, with a too narrow bikelane on the side. The sidewalk comes down to the street before the pedestrian rises above the street, and then returns to grade before the next accessibility ramp. Not quite an elegant solution.
Redfern Station Entrance. There is no marked crosswalk, much less a speed hump or raised sidewalk here, despite the huge demand. There is however a speedhump just to the east (left) of the picture for some reason. A missed opportunity. No marked crosswalk means pedestrians must yield to cars.
Redfern Station Entrance. There is no marked crosswalk, much less a speed hump or raised sidewalk here, despite the huge demand. There is however a speedhump just to the east (left) of the picture for some reason. A missed opportunity. No marked crosswalk means pedestrians must yield to cars.
The intersection of Abercrombie Street and Cleveland Street in Darlington (Chippendale is across Cleveland) sees a speed hump on Abercrombie between Hudson Street (the lower right) and Cleveland (upper right). Pedestrians are continuously crossing in this stretch, but the speed hump aligns with neither unmarked crosswalk. Still, it's begging for pedestrians to use it, and they do.
The intersection of Abercrombie Street and Cleveland Street in Darlington (Chippendale is across Cleveland) sees a speed hump on Abercrombie between Hudson Street (the lower right) and Cleveland (upper right). Pedestrians are continuously crossing in this stretch, but the speed hump aligns with neither unmarked crosswalk (at Hudson/Abercrombie nor Cleveland/Abercrombie). Still, it’s begging for pedestrians to use it, and they do.
A signalized but porkchop-islanded crosswalk at a Free Left (Free Right for those in the right-side drive countries). Notice the pedestrian light is red (don't walk) but the pedestrians cross anyway. If the free left is not eliminated in a more comprehensive redesign, it could easily be de-signaled and the crosswalk raised, so pedestrians dominate, and cars travel when they can.
A signalized but porkchop-islanded crosswalk at a Free Left (Free Right for those in the right-side drive countries) (Broadway and City Road). Notice the pedestrian light is red (don’t walk) but the pedestrians cross anyway. If the free left is not eliminated in a more comprehensive redesign, it could easily be de-signaled and the crosswalk raised, so pedestrians dominate, and cars travel when they can.
This speed bump does not want to be mistaken for a pedestrian crossing, so it is landscaped whereever a pedestrian might think of crossing. This is just before the actual intersection, on an extensively calmed street.
This speed bump in Alexandria Park does not want to be mistaken for a pedestrian crossing, so it is landscaped wherever a pedestrian might think of crossing. This is just before the actual intersection, on an extensively calmed street. Cars race from calming device to calming device, treating the chicanes the way a skier might.

Spontaneous Access: Reflexions on Designing Cities and Transport – Now in print

Spontaneous Access: Reflexions on Designing Cities and Transport is now available as a high-quality color trade paperbackIt is also available in hardcover.

It remains available as an eBook on Kindle Editions  and at the iBookstore. If you have the option, I encourage you to get it on Apple’s iBooks, where it has additional features, like pop-up references and image galleries, as it was designed in ePub3.

Spontaneous Cover-Front

Table of Contents

  1. The City Spontaneous
  2. The 60-Year Line
  3. Community without dendricity
  4. The pint-of-milk test
  5. The timeless way of building networks
  6. Axioms about roads
  7. Garden streets
  8. Vitality
  9. An archipelago of walkability
  10. Filling in
  11. Leapin’ frogs
  12. The reorganization of road function
  13. Beyond the plan view
  14. Interfaces of freedom
  15. Instruments of control
  16. Shared space
  17. Winter is coming
  18. Diversity as insurance
  19. Differentiate city and country
  20. Don’t confuse the place for the time
  21. Great Britain doesn’t have an Americans with Disabilities Act
  22. Designs serve varied and sometimes conflicting interests
  23. A vision of visions
  24. A faster horse
  25. The Ant and the Grasshopper
  26. Deconstructing Busytown
  27. Spontaneity in a can, spontaneity in a plan
  28. Building the city spontaneous
  29. Framing regional development
  30. First do no harm

There are several themes in the book:

Cities and their networks operate on multiple timescales simultaneously. Traffic lights change by the second, rights-of-way last millennia. Cities see massive daily flows of people in and out. The core, timeless, enduring elements contrast with the faddish ephemera that too much effort is focused on. The future is emerging, but determining what we are looking forward to will be enduring or ephemeral should be the critical focus of anyone involved with transport and city design.

This book does not shy away from the normative and prescriptive. In this it differs from much academic work, including my own, which tends to the positive and descriptive. Principles are laid out, which I believe to be true and correct, many of which are not scientific in the way they are framed. They of course may lead to testable hypotheses, but they are also value-based.

The idea of the ‘spontaneous city,’ one that serves needs and wants in real-time, is a theme running through both the title and the text. What conditions encourage people to take advantage of their city (and therefore make it stronger)? What conditions worsen life for the users of the city?

The emergence of new transport technologies gives us a chance to restore and correct, to right what is wrong with the places we live. From the railroad and electric streetcar creating separation between places where people lived and where they worked, to the elevator enabling high rise construction, to the motorcar which put suburbanization into over- drive, all significant transport innovations reshape cities. The new autonomous vehicle, the new electric vehicle, the new shared vehicle, the vehicle form, shape, and size are a transformation of similar scale and scope. These changes will create opportunities over the coming decades, which we can seize or reject.

This book is about how cities do work, how cities can work, and how cities should work. In part it is about traditional fields of planning and engineering, but takes a much broader concept of design principles than those fields usually do. This is because it is also about evolution and it is about opportunism. The world is changing fast. We can make it a more humane place than it has ever been, or we can allow it to devolve into a more brutish environment, where we remain a victim of our collectively built environments, rather than their master.

When the book speaks of ‘cities’ it really means the entire metropolitan ‘urban system,’ not just the historic core city (or the central business district). Downtown is but a part of the city, and the central city in many metropolises is not even a plurality of residents.

Much of this book includes complaint, and it may feel like shouting into the wind. But every complaint is about a design failure, either with intention or by accident, that degrades experience for everyone, or degrades the experience of some for the benefit of others. Life is comprised of tradeoffs, but not all tradeoffs are made at the appropriate rate of exchange. Both cities and their transport networks are the product of thoughtful human actions and unconscious emergent processes, where systematic behavior drives the underlying logic of designs.

The optimal design of transport networks to serve the goal of spontaneous access cannot be determined in the absence of knowledge about the actual development pattern. The optimal development pattern cannot be known without regards to the plan of the network. Discovering the right combinations of networks, land use, and other urban features is what makes cities successful. The measure of their success is their population, their wealth, their happiness.

But even more importantly, the optimal transport network for the technology of one era is not necessarily the optimal network of the future, and the same is true for development.


Much of Spontaneous Access is drawn from my blog transportist.org, or streets.mn, although it has been significantly edited and reorganized from posts that may have appeared there. In that sense, it is a younger sibling to the recent (2015) book The End of Traffic and the Future of Transport with Kevin Krizek. It is a collection of reflexions (a somewhat archaic British way of spelling “reflections”), short essays that collectively give insight into today’s design problems and some possible solutions.

Spontaneous Access: Reflexions on Designing Cities and Transport on sale for $0.99 at Amazon Kindle TODAY only

Spontaneous Access: Reflexions on Designing Cities and Transport on sale for $0.99 at Amazon Kindle TODAY (March 9, 2017) only.

Spontaneous Access: Reflexions on Designing Cities and Transport. By David M. Levinson

Table of Contents

  1. The City Spontaneous
  2. The 60-Year Line
  3. Community without dendricity
  4. The pint-of-milk test
  5. The timeless way of building networks
  6. Axioms about roads
  7. Garden streets
  8. Vitality
  9. An archipelago of walkability
  10. Filling in
  11. Leapin’ frogs
  12. The reorganization of road function
  13. Beyond the plan view
  14. Interfaces of freedom
  15. Instruments of control
  16. Shared space
  17. Winter is coming
  18. Diversity as insurance
  19. Differentiate city and country
  20. Don’t confuse the place for the time
  21. Great Britain doesn’t have an Americans with Disabilities Act
  22. Designs serve varied and sometimes conflicting interests
  23. A vision of visions
  24. A faster horse
  25. The Ant and the Grasshopper
  26. Deconstructing Busytown
  27. Spontaneity in a can, spontaneity in a plan
  28. Building the city spontaneous
  29. Framing regional development
  30. First do no harm

There are several themes in the book: 

Cities and their networks operate on multiple timescales simultaneously. Traffic lights change by the second, rights-of-way last millennia. Cities see massive daily flows of people in and out. The core, timeless, enduring elements contrast with the faddish ephemera that too much effort is focused on. The future is emerging, but determining what we are looking forward to will be enduring or ephemeral should be the critical focus of anyone involved with transport and city design.

This book does not shy away from the normative and prescriptive. In this it differs from much academic work, including my own, which tends to the positive and descriptive. Principles are laid out, which I believe to be true and correct, many of which are not scientific in the way they are framed. They of course may lead to testable hypotheses, but they are also value-based.

The idea of the ‘spontaneous city,’ one that serves needs and wants in real-time, is a theme running through both the title and the text. What conditions encourage people to take advantage of their city (and therefore make it stronger)? What conditions worsen life for the users of the city?

The emergence of new transport technologies gives us a chance to restore and correct, to right what is wrong with the places we live. From the railroad and electric streetcar creating separation between places where people lived and where they worked, to the elevator enabling high rise construction, to the motorcar which put suburbanization into over-drive, all significant transport innovations reshape cities. The new autonomous vehicle, the new electric vehicle, the new shared vehicle, the vehicle form, shape, and size are a transformation of similar scale and scope. These changes will create opportunities over the coming decades, which we can seize or reject.

This book is about how cities do work, how cities can work, and how cities should work. In part it is about traditional fields of planning and engineering, but takes a much broader concept of design principles than those fields usually do. This is because it is also about evolution and it is about opportunism. The world is changing fast. We can make it a more humane place than it has ever been, or we can allow it to devolve into a more brutish environment, where we remain a victim of our collectively built environments, rather than their master.

When the book speaks of ‘cities’ it really means the entire metropolitan ‘urban system,’ not just the historic core city (or the central business district). Downtown is but a part of the city, and the central city in many metropolises is not even a plurality of residents.

Much of this book includes complaint, and it may feel like shouting into the wind. But every complaint is about a design failure, either with intention or by accident, that degrades experience for everyone, or degrades the experience of some for the benefit of others. Life is comprised of tradeoffs, but not all tradeoffs are made at the appropriate rate of exchange. Both cities and their transport networks are the product of thoughtful human actions and unconscious emergent processes, where systematic behavior drives the underlying logic of designs.

The optimal design of transport networks to serve the goal of spontaneous access cannot be determined in the absence of knowledge about the actual development pattern. The optimal development pattern cannot be known without regards to the plan of the network. Discovering the right combinations of networks, land use, and other urban features is what makes cities successful. The measure of their success is their population, their wealth, their happiness.

But even more importantly, the optimal transport network for the technology of one era is not necessarily the optimal network of the future, and the same is true for development.


Much of Spontaneous Access is drawn from my blog transportist.org, or streets.mn, although it has been significantly edited and reorganized from posts that may have appeared there. In that sense, it is a younger sibling to the recent (2015) book The End of Traffic and the Future of Transport with Kevin Krizek. It is a collection of reflexions (a somewhat archaic British way of spelling “reflections”), short essays that collectively give insight into today’s design problems and some possible solutions.

Spontaneous Access: Reflexions on Designing Cities and Transport

Spontaneous Access: Reflexions on Designing Cities and Transport is now on sale via a Countdown Promotion on Amazon’s Kindle Editions for a limited time only. Act quickly.

SPONTANEOUS ACCESS: REFLEXIONS ON DESIGNING CITIES AND TRANSPORT

I am pleased to announce the publication of my latest book: Spontaneous Access: Reflexions on Designing Cities and Transport on Kindle Editions  and at the iBookstore. The list price is $8.99. If you have the option, I encourage you to get it on Apple’s iBooks, where it has additional features, like pop-up references and image galleries, as it was designed in ePub3.

Spontaneous Access: Reflexions on Designing Cities and Transport. By David M. Levinson

Table of Contents

  1. The City Spontaneous
  2. The 60-Year Line
  3. Community without dendricity
  4. The pint-of-milk test
  5. The timeless way of building networks
  6. Axioms about roads
  7. Garden streets
  8. Vitality
  9. An archipelago of walkability
  10. Filling in
  11. Leapin’ frogs
  12. The reorganization of road function
  13. Beyond the plan view
  14. Interfaces of freedom
  15. Instruments of control
  16. Shared space
  17. Winter is coming
  18. Diversity as insurance
  19. Differentiate city and country
  20. Don’t confuse the place for the time
  21. Great Britain doesn’t have an Americans with Disabilities Act
  22. Designs serve varied and sometimes conflicting interests
  23. A vision of visions
  24. A faster horse
  25. The Ant and the Grasshopper
  26. Deconstructing Busytown
  27. Spontaneity in a can, spontaneity in a plan
  28. Building the city spontaneous
  29. Framing regional development
  30. First do no harm

There are several themes in the book: 

Cities and their networks operate on multiple timescales simultaneously. Traffic lights change by the second, rights-of-way last millennia. Cities see massive daily flows of people in and out. The core, timeless, enduring elements contrast with the faddish ephemera that too much effort is focused on. The future is emerging, but determining what we are looking forward to will be enduring or ephemeral should be the critical focus of anyone involved with transport and city design.

This book does not shy away from the normative and prescriptive. In this it differs from much academic work, including my own, which tends to the positive and descriptive. Principles are laid out, which I believe to be true and correct, many of which are not scientific in the way they are framed. They of course may lead to testable hypotheses, but they are also value-based.

The idea of the ‘spontaneous city,’ one that serves needs and wants in real-time, is a theme running through both the title and the text. What conditions encourage people to take advantage of their city (and therefore make it stronger)? What conditions worsen life for the users of the city?

The emergence of new transport technologies gives us a chance to restore and correct, to right what is wrong with the places we live. From the railroad and electric streetcar creating separation between places where people lived and where they worked, to the elevator enabling high rise construction, to the motorcar which put suburbanization into over- drive, all significant transport innovations reshape cities. The new autonomous vehicle, the new electric vehicle, the new shared vehicle, the vehicle form, shape, and size are a transformation of similar scale and scope. These changes will create opportunities over the coming decades, which we can seize or reject.

This book is about how cities do work, how cities can work, and how cities should work. In part it is about traditional fields of planning and engineering, but takes a much broader concept of design principles than those fields usually do. This is because it is also about evolution and it is about opportunism. The world is changing fast. We can make it a more humane place than it has ever been, or we can allow it to devolve into a more brutish environment, where we remain a victim of our collectively built environments, rather than their master.

When the book speaks of ‘cities’ it really means the entire metropolitan ‘urban system,’ not just the historic core city (or the central business district). Downtown is but a part of the city, and the central city in many metropolises is not even a plurality of residents.

Much of this book includes complaint, and it may feel like shouting into the wind. But every complaint is about a design failure, either with intention or by accident, that degrades experience for everyone, or degrades the experience of some for the benefit of others. Life is comprised of tradeoffs, but not all tradeoffs are made at the appropriate rate of exchange. Both cities and their transport networks are the product of thoughtful human actions and unconscious emergent processes, where systematic behavior drives the underlying logic of designs.

The optimal design of transport networks to serve the goal of spontaneous access cannot be determined in the absence of knowledge about the actual development pattern. The optimal development pattern cannot be known without regards to the plan of the network. Discovering the right combinations of networks, land use, and other urban features is what makes cities successful. The measure of their success is their population, their wealth, their happiness.

But even more importantly, the optimal transport network for the technology of one era is not necessarily the optimal network of the future, and the same is true for development.


Much of Spontaneous Access is drawn from my blog transportist.org, or streets.mn, although it has been significantly edited and reorganized from posts that may have appeared there. In that sense, it is a younger sibling to the recent (2015) book The End of Traffic and the Future of Transport with Kevin Krizek. It is a collection of reflexions (a somewhat archaic British way of spelling “reflections”), short essays that collectively give insight into today’s design problems and some possible solutions.

Escape with Spontaneous Access

Election news got you down? Escape with Spontaneous Access this weekend. It’s 50,000 or so mostly non-fiction, yet highly entertaining, words which have essentially nothing to do with national politics.

Spontaneous Access: Reflexions on Designing Cities and Transport by David Levinson is now available at the iBookstore (best for Apple Mac/iPad/iPhone users) or Kindle Editions  (everyone else). On sale for only $4.99,  it will let you will travel much further than the two gallons of gas it would otherwise buy. To motivate you even more, the first chapter: The City Spontaneous, is available for free. (link below)

Spontaneous Access: Reflexions on Designing Cities and Transport by David Levinson
Spontaneous Access: Reflexions on Designing Cities and Transport by David Levinson

Table of Contents

  1. The City Spontaneous
  2. The 60-Year Line
  3. Community without dendricity
  4. The pint-of-milk test
  5. The timeless way of building networks
  6. Axioms about roads
  7. Garden streets
  8. Vitality
  9. An archipelago of walkability
  10. Filling in
  11. Leapin’ frogs
  12. The reorganization of road function
  13. Beyond the plan view
  14. Interfaces of freedom
  15. Instruments of control
  16. Shared space
  17. Winter is coming
  18. Diversity as insurance
  19. Differentiate city and country
  20. Don’t confuse the place for the time
  21. Great Britain doesn’t have an Americans with Disabilities Act
  22. Designs serve varied and sometimes conflicting interests
  23. A vision of visions
  24. A faster horse
  25. The Ant and the Grasshopper
  26. Deconstructing Busytown
  27. Spontaneity in a can, spontaneity in a plan
  28. Building the city spontaneous
  29. Framing regional development
  30. First do no harm

Spontaneous Access: Reflexions on Designing Cities and Transport

Spontaneous Access: Reflexions on Designing Cities and Transport by David Levinson
Spontaneous Access: Reflexions on Designing Cities and Transport by David Levinson

I am pleased to announce the publication of my latest book: Spontaneous Access: Reflexions on Designing Cities and Transport on Kindle Editions  and at the iBookstore. The price is $4.99. If you have the option, I encourage you to get it on Apple’s iBooks, it has additional features.

Table of Contents

  1. The city spontaneous
  2. The 60-Year Line
  3. Community without dendricity
  4. The pint-of-milk test
  5. The timeless way of building networks
  6. Axioms about roads
  7. Garden streets
  8. Vitality
  9. An archipelago of walkability
  10. Filling in
  11. Leapin’ frogs
  12. The reorganization of road function
  13. Beyond the plan view
  14. Interfaces of freedom
  15. Instruments of control
  16. Shared space
  17. Winter is coming
  18. Diversity as insurance
  19. Differentiate city and country
  20. Don’t confuse the place for the time
  21. Great Britain doesn’t have an Americans with Disabilities Act
  22. Designs serve varied and sometimes conflicting interests
  23. A vision of visions
  24. A faster horse
  25. The Ant and the Grasshopper
  26. Deconstructing Busytown
  27. Spontaneity in a can, spontaneity in a plan
  28. Building the city spontaneous
  29. Framing regional development
  30. First do no harm

There are several themes in the book: 

Cities and their networks operate on multiple timescales simultaneously. Traffic lights change by the second, rights-of-way last millennia. Cities see massive daily flows of people in and out. The core, timeless, enduring elements contrast with the faddish ephemera that too much effort is focused on. The future is emerging, but determining what we are looking forward to will be enduring or ephemeral should be the critical focus of anyone involved with transport and city design.

This book does not shy away from the normative and prescriptive. In this it differs from much academic work, including my own, which tends to the positive and descriptive. Principles are laid out, which I believe to be true and correct, many of which are not scientific in the way they are framed. They of course may lead to testable hypotheses, but they are also value-based.

The idea of the ‘spontaneous city,’ one that serves needs and wants in real-time, is a theme running through both the title and the text. What conditions encourage people to take advantage of their city (and therefore make it stronger)? What conditions worsen life for the users of the city?

The emergence of new transport technologies gives us a chance to restore and correct, to right what is wrong with the places we live. From the railroad and electric streetcar creating separation between places where people lived and where they worked, to the elevator enabling high rise construction, to the motorcar which put suburbanization into over- drive, all significant transport innovations reshape cities. The new autonomous vehicle, the new electric vehicle, the new shared vehicle, the vehicle form, shape, and size are a transformation of similar scale and scope. These changes will create opportunities over the coming decades, which we can seize or reject.

This book is about how cities do work, how cities can work, and how cities should work. In part it is about traditional fields of planning and engineering, but takes a much broader concept of design principles than those fields usually do. This is because it is also about evolution and it is about opportunism. The world is changing fast. We can make it a more humane place than it has ever been, or we can allow it to devolve into a more brutish environment, where we remain a victim of our collectively built environments, rather than their master.

When the book speaks of ‘cities’ it really means the entire metropolitan ‘urban system,’ not just the historic core city (or the central business district). Downtown is but a part of the city, and the central city in many metropolises is not even a plurality of residents.

Much of this book includes complaint, and it may feel like shouting into the wind. But every complaint is about a design failure, either with intention or by accident, that degrades experience for everyone, or degrades the experience of some for the benefit of others. Life is comprised of tradeoffs, but not all tradeoffs are made at the appropriate rate of exchange. Both cities and their transport networks are the product of thoughtful human actions and unconscious emergent processes, where systematic behavior drives the underlying logic of designs.

The optimal design of transport networks to serve the goal of spontaneous access cannot be determined in the absence of knowledge about the actual development pattern. The optimal development pattern cannot be known without regards to the plan of the network. Discovering the right combinations of networks, land use, and other urban features is what makes cities successful. The measure of their success is their population, their wealth, their happiness.

But even more importantly, the optimal transport network for the technology of one era is not necessarily the optimal network of the future, and the same is true for development.


Much of Spontaneous Access is drawn from my blog transportist.org, or streets.mn, although it has been significantly edited and reorganized from posts that may have appeared there. In that sense, it is a younger sibling to the recent (2015) book The End of Traffic and the Future of Transport with Kevin Krizek. This book too talks about access, that is why we build transport in the first place. It is a collection of reflexions (a somewhat archaic British way of spelling “reflections”)

Garden Streets

SPONTANEOUS ACCESS: REFLEXIONS ON DESIGNING CITIES AND TRANSPORT by David Levinson
SPONTANEOUS ACCESS: REFLEXIONS ON DESIGNING CITIES AND TRANSPORT by David Levinson

One of the most influential planning ideas to emerge from the late 19th century was that of the Garden City. Ebenezer Howard, in his book Garden Cities of To-Morrow proposed constructing these new towns in the outer orbit of metropolitan London. The aim was to fuse the best of the city and the country.  Several were realized, including Letchworth (pictures 1 and 2) and  Welwyn Garden City, (pictures) which I had the opportunity to visit in 2006/07. The idea became a foundation for many subsequent new town plans in the UK and influence places in the US like Columbia, Maryland. It today can be seen in a way as a ante-cedent to the New Urbanist movement. Places like Kentlands in Maryland are not complete Garden Cities, but certainly share many elements.

Howard-three-magnets
Howard’s Three Magnets

The idea was carried forward into Garden Suburbs, smaller units that were not as economically independent. Hampstead Garden Suburb (picture) is the original example of this development. It is lovely, and very expensive.

The phrase Garden Streets occurred to me at some point. What would this mean? In one sense, we can think of complete streets, that function for all users, not just motor vehicles. These typically have various lanes, for pedestrians, for trees, for drainage, for bicycles, for buses, for cars.  Alternatively it might be a shared street, one where the modes were not channelized, but floated freely amongst each other. But neither of those in themselves really get at the core idea.

The phrase also brings out the idea of formal or naturalistic landscaping, as one envisions from a Boulevard in a neighborhood designed by Frederick Law Olmsted.  In London, the term apparently refers to streets where any unpaved (and some paved) areas are intensively landscaped by neighbors, guerrilla gardeners, as shown in the attached YouTube video.

 

I think this meaning is closer, but too literal.

Instead, if we bring out the original sense of Garden Cities, we want to fuse the best aspects of town and country. The best country roads, with their naturalistic landscaping are places we want to drive, ride, or walk. The best city streets  with their more intensive use, still create interest if we see places we enjoy walking past because they look, sound, and smell interesting. A Garden Street fuses the best of both creating a street that is desirable to be on, because there is something interesting to see, either nature or an intense and interesting urban environment.

So the Garden Street doesn’t adjoin non-descript blacktop for storing cars, or chain linked fences, or anything that lacks beauty. Instead it aspires to the aphorism that the Journey is the Reward. The Garden Street is not traversed simply to get from here to there, but because it is a preferred place to be, the Garden Street invites you and encourages you to travel on it. It successfully competes with the screen in front of you as place to be.

Some examples are below. Three are shopping streets, two are residential. They are not perfect illustrations (Nara could be lusher), but they are places one wants to be walking in, streets one wants be on, rather than through.

Sometimes a city is a tree

Christopher Alexander wrote a brilliant essay in 1965: “A City is not a Tree“. Long interested in Alexander’s work since graduate school in Berkeley, I recently re-read the piece which has been packaged in a 50th anniversary volume. The original article is available online free. There have been numerous other papers that have commented on various aspects Alexander’s piece, I can’t list them all, it has been cited over 1000 times.

SPONTANEOUS ACCESS: REFLEXIONS ON DESIGNING CITIES AND TRANSPORT by David Levinson
SPONTANEOUS ACCESS: REFLEXIONS ON DESIGNING CITIES AND TRANSPORT by David Levinson

Alexander criticizes new towns, notably my home town, Columbia, Maryland, for being treelike in its conception, rather than what he terms a semi-lattice, but we would more informally call a mesh-like network. The neighborhoods belong to villages, the villages are part of the city. The neighborhoods, following an element of the Radburn plan, are isolated, that is, one cannot go from one neighborhood to another without being on a village street. That’s not to say there is no through traffic, there is, because the neighborhood network has more than one outlet.

But it’s not simply the street network that is tree like, retail is also tree-like. The neighborhood center might have a convenience store (7-11 or Wawa), the village center would have a grocery and 10-20 smaller stores. Town Center had the Mall in Columbia with department stores and over 100 shops. Perhaps Walter Christaller would be proud that Central Place Theory was not merely descriptive, but also prescriptive.

Finally the schools were tree-like. The neighborhood elementary school fed the village-level Middle and High schools.

In practice it was not so tree-like. As a resident of the neighborhood of Bryant Woods in the Village of Wilde Lake, my mom could go shopping at a supermarket at Joseph Square shopping center in the Village of Harper’s Choice. It was only another mile down the road. Later as a resident of Longfellow neighborhood, I could open-enroll into Wilde Lake Middle School. And of course not every neighborhood got an elementary school, not every village got a Middle or High School, and the boundaries were overlapping. So while the stylized schematic drawing may have looked treelike from the perspective of an architect a few thousand miles away, it was not treelike in practice on the ground. See The Next America Revisited for my take.

treenessI don’t believe the planners envisioned it would be so tidy — though better to start out tidy and let entropy emerge rather than start out chaotic and hopes it self-organizes into an aesthetically pleasing environment. Rather my impression from reading a lot of the documents and having lived there and hearing talks from Rouse company officials and so on is that they believed that treelike street networks reduced through traffic, just as planners favor traffic calming today. They believed shopping should be organized into centers, rather than sprawled out uncontrolled along streets, and they should be spaced to be closer to residents. They believed local government is somewhat hierarchical (national, state, county, city) and that village was an organization unit that had some value to regulate things at a more local level than the city (Columbia is not technically a city, it’s just a home owners association, though it is a Census-Defined Place and the second largest in Maryland, after Baltimore, just as was foretold in the 1960s). They believed kids should walk to their neighborhood school, so the neighborhood should be the right size to support the school, which should have X students for pedagogical and cost-efficiency reasons, and ideally students would walk to their middle and high school too, but that middle and high schools should be larger. So the hierarchy was a natural way of organizing that.

But even if Columbia is innocent of being as treelike as Alexander feared (and certainly some new towns were more treelike), the suburbs are certainly more treelike than cities. My students have measured the “treeness” of networks, introducing the metric in Xie and Levinson (2007) Measuring the Structure of Road Networks. For instance in Network structure and the journey to work: An intra-metropolitan analysis (under review) by Pavithra Parthasarathi and myself, we see that treeness is not surprisingly higher at the suburban edges of the metropolitan area than in the center, though it declines as we see rural areas, where the sparser network is also more mesh or grid-like. (See figure)

Still, sometimes the city is a tree, or at least aspects of it are. In particular, many networked physical infrastructures are better organized as trees, especially if they require a large capital investment (like a waste water treatment facility). Similarly, the stream and river valleys are naturally organized as hierarchies. Transit networks are also often more treelike or radial than roads, and while may eventually evolve into ring-radial system, don’t generally start out that way. See Roth et al. 2012.

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This transit network looks pretty tree-like.

Clearly social connections should not be assumed to flow in a way that maps directly to the physical layout of the network, all other things being equal, you are more likely to know your neighbor than a randomly selected person farther away. Yet, in a modern world with migration and telecommunication, you are likely to know someone specifically who is not on your block and to not  know everyone on your street. Growing up, my mom’s friends were scattered across Columbia, not just in her neighborhood. ‘Community without propinquity’ was first identified by Berkeley Planner Mel Webber, and certainly applied in Columbia as it does everywhere, where people could meet based on any kind of interest, not simply the desire to live on the same street. The physical form of the city does not represent how the city works, but more importantly the plans do not determine how the city works. People and their relationships are affected by their environment, and reshape it to suit their needs.