Rethinking Cities

Lately I've been thinking about the adverse impact of cars on our landscape. Most familiar are of course oil use, pollution, noise and traffic. Less commonly discussed are things like:

  • fatalities, injuries and accidents compared to other forms of transportation
  • miles of pavement in the form of parking lots and roads which contribute to stormwater issues
  • the sprawl of suburbia enabled by widespread car ownership.

But beyond even these things, I've started thinking about:

  • the primacy of cars and trucks over pedestrian and bike traffic (is it a natural condition to fear for your life walking across a road?)
  • the space taken up by the industries supporting or necessitated by a car-ful society (dealers with oceans of parking lots for their unsold vehicles, mechanics and gas stations)
  • the wasted time of police monitoring vehicle traffic.
  • how people can feel stranded and isolated if they do not have a car to travel the ever-increasing distances from where they live to where they need to be to work, socialize and shop.

There are surely more.

This line of thought started early this spring when I found Car Free Cities via a comment on Colin Beavan's blog. It described a plan for urban life that eliminated the need for cars (and trucks and buses). The stated goals of the car-free plan reclaiming urban space for people rather than vehicles, restoring social fabric and quality of urban life, with an eye to environmental benefits and energy efficiency.

I should note right away that this is only a design for cities. As the author JH Crawford states, there is no clear, desirable solution for eliminating cars and trucks in rural areas.

Design Metrics

There is an extensive list of design metrics that Crawford lists in his book to inform his design. Some of the broader aspects of the results are:

  • A reference design that comfortably supports 2 million people working and living.
  • Walkable mixed-use districts connected by mass transit depots at the center of each. A topology of districts that maximizes public transportation efficiency.
  • Streets limited to pedestrians, bikes, with permits for low-speed electric vehicles, and when necessary emergency and construction vehicles.
  • Ample green space within a short walking distance from every front door.
  • An average building height of 4 floors, of varying unique architectures.
  • Freight and mass transit handled below-grade by separate subway lines

A Car Free Athens

The idea looks radical, but reasonable. It tries not to make too many decisions about how we lead our lives aside from three: transportation, density, and green-space. There are suggestions and implications within about energy generation, urban social life and more, but these are ideas rather than prescriptions.

I wondered what it would look like in the city I now live in. A lot of the talk on the car free forum is about building districts or even whole cities from scratch, but I was more attracted to the idea of transitioning the existing areas of the city to the new design.

Athens has no subway (it has a growing bus system), a vibrant downtown and a lot of suburbs. Its major roads are actually already laid out radially which could be well suited to adapting it to the reference topology Crawford presents. So I started delving into what I could find online for maps and reference data. My goal was to hew closely to the plan advocated in the book, and so I wanted to understand what existing infrastructure and institutions could be accommodated, and which would have to go.

I mapped out the existing hospitals and schools, historic districts, bodies of water and took into account where metro stops could line up with existing roads, where they would be immediately useful even before the city went fully car free. I found that I couldn't quite get all the schools to fall within the urban districts using the reference topology, but those which did not make it in were few. I should also note that my current house would not fall within the diameter (just barely) of the carfree city design. Likewise the historic districts didn't line up well with the plan for the car free districts, but in truth most if not all of these historic homes are single-family units of no more than two stories -- it is unlikely they would provide the necessary density as advocated by the car free plan. Crawford advocates green space surrounding all the urban districts, and with good cause, but exceptions could be made for the sake of historic preservation.

One of the major stumbling blocks for building a subway system as advocated by Crawford is Athens' topography. If you've been to Athens you'll know it's fairly hilly in places. As one example, from the center of downtown to the river there's an elevation change of 53 meters over a 700 meter distance. That 7.9% grade is far steeper than ideal grades for a railway which do not exceed 1%.

Grade separation (keeping different modes of transportation from interfering with each other) is paramount to an efficient mass transit system. Ideally (for issues of weather cover and train automation) the whole system would function best underground. However, given the extreme changes in elevation around downtown there may need to be some compromises. These would probably be done at either extreme; burying some of the highest elevation subway-stops deeper underground than would usually be done, and having the subway emerge onto an elevated track over some of the deepest valleys.


Stages of Development

The Walmart District

To get a practical sense of how big one of these walkable districts is, I overlayed a circle of the proper diameter (760 meters) on one of the shopping areas in Athens. What you see here is a Walmart (white roof) and a Lowe's (dark roof) off one of the major arteries southwest of Athens. The large patches of dirt are now strip malls. So the car free plan would provide housing for twelve thousand people and work for eight-thousand (for the sake of calculation, schooling is considered "work" for the children of the district) in the space of two big box stores and two strip malls. This may feel claustrophobic to those used to suburban living (I'll attest to that myself), but take away the noise, pollution and expanses of pavement for driving and parking cars and trucks, and it instantly becomes a much more pleasant place to be.

Putting aside for the moment that Athens isn't even currently considering a subway, what could the stages of development be to transition the city to the car free plan?

I think I would start with making downtown progressively car free. It is already a heavily pedestrian environment, given that the UGA campus is just to the south of Broad Street. It would help acclimate people to car free living. The many parking lots could be turned instead into more shops with living spaces on the upper floors.

Ultimately I would look to make the north-south streets into pedestrian right-of-ways (bikes allowed but with caution), and the east-west streets as bike-ways (with ample room on the edges for pedestrians, of course). I'd probably start by turning College Ave into a series of plazas, intersected by the east-west roads, as this is the heart of downtown. Next the city could limit downtown delivery vehicles to blocks of time in the morning and night, similiar to Lisbon's Bairro Alto area.

The other item that could be changed early on is to rezone the areas that would become car free districts to allow for mixed use and to allow a building height appropriate for the desired population density.

The biggest undertaking would be to begin building the subway. Securing the rights of way for the trains (both passenger and freight) will probably be as big an issue as finding funding for the system as a whole. That sort of work ought to begin immediately, as you do not want people investing in and building on space that will ultimately be reclaimed for the transit system.

The subway will have to be built in stages, if for no other reason than that Athens does not have the population to merit as extensive a system as laid out in the reference topology. The city's population is just over 110 thousand, a mere 5 percent of the suggested city in the book. Whether it makes more sense to develop one of the 3 subway lines at a time, or start on them all from the middle out and extend them as the population merits it, I do not know. In either case, while the ends of the line or lines are under construction, the subway can begin to operate on the finished sections by shuttling back and forth until a loop is complete.

The other subway question is when to introduce the "metro freight" concept, where all goods coming into and leaving the city are transferred by standardized shipping containers on a below-grade rail system. Getting people out of their cars and into mass transit is only half the equation. We will still be saddled with the noise, pollution and safety risks of surface vehicles if we do not have an efficient and desirable way to move goods around. I would suggest that this won't be viable until at least a few of the "utility districts" proposed in the car free plan are implemented, complete with a well developed intercity rail link for freight.

Intercity rail for passengers will need to be addressed as well. For the forseeable future there will still be a large number of commuters into metro-Atlanta, and it would be a shame if they had to take the subway out of the edge of the city only to have to get in their car and drive the rest of the way in. A commuter rail link has been a long time coming, and it's unclear when that will finally come to pass.

Other Considerations

While working through the car free idea I've gathered a number of ideas and considerations not mentioned in Crawford's writings:

Passages for wildlife: each district is connected to its neighboring district by a boulevard for bike/ pedestrian/ emergency vehicle traffic. Since the rest of the district borders on green space, it would probably be wise to engineer wildlife corridors under or over these roads.

Private outdoor space: something I am used to as a resident of suburbia is private outdoor space to cultivate as I choose. Is this something that is inherently impossible in a city? Is my gardening/landscaping hobby not compatible? Would we need to be able to afford a "country home" to indulge in these hobbies? Does that leave this activity only available to the wealthy?

Subway station designs: Having been an architecture student in a past life, I'd like to think that we could make subway stops that are bright and full of natural light, rather than feeling like caves. Crawford's plans puts the metro stops under the main boulevard running through each district. This may be an efficient use of space, but limits the sort of architecture possible to make them inviting spaces.

Hospitals: Crawford mentions locating hospitals in the middle of the green space within each subway loop. I would rather see that remain green space and instead see clinics built in each district.

Planning: It might be a useful planning tool to have a heat-map of the age of all buildings/locations in the existing city. Both for historical preservation and for individual sentimental value, it may be hard to persuade citizens to raze older structures as part of the reorganization of the city. It could bias districts to include these areas rather than leaving them in the designated green areas for reclamation.