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Voices Cities

Let’s build cities for people (not cars)

Richard RegisterEcocity Builders

Richard Register is founder and president of Ecocity Builders and was founding president of Urban Ecology, both nonprofit educational organizations. He is author of Ecocities: Building cities in balance with nature (Berkley Hills Books, 2001), Ecocity Berkeley: Building cities for a healthy future (North Atlantic Books, 1987), and Another Beginning (Treehouse Books, 1978). He has traveled the equivalent of 28 times around the world advocating for the potential of the pedestrian city to save the world.

How big can cities get? Aristotle thought a population of 10,000 was too small for a vibrant democratic city and 20,000 too big. On the other hand, Jeff Kenworthy, the renowned Australian environmental scientist who with his colleague Peter Newman has done groundbreaking work on city size and sustainability, told me once that they he and Peter were surprised and a little disturbed because their research showed that the most efficient size for cities was so large as to not yet be identified. We simply haven’t gotten there yet.

That, of course, is counter intuitive for anyone who’s ever looked up and observed the plumes of air pollution that now emanate from cities, spreading, braiding, and blending across the globe into a seamless blanket of gray-yellow-brown. Cities as we now build them are so voracious in appetite, so demanding of energy, that we’re forced to risk environmental disasters like the British Petroleum oil well that blew out in the Gulf of Mexico in April 2010 in order to sustain them. Given all that, the idea of building them even bigger seems foolish, perhaps even dangerous. It also suggests that what we think of as efficient for production, employment and economics is not in tune with ecological efficiency. Thinking of cities as healthy parts of an ecological system might bring those ideas back into alignment.

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Whatever the optimal size of the 21st century city, it must be measured in relation to quite a few other factors. Ecologists see organisms as interrelated parts of living systems. We should view the elements of our urban ecosystems in this way too. Doing so helps to explain the disparity between Aristotle and Kenworthy. The urban ecosystem is vastly more complex today than in the days of ancient Greece.

As a teenager my first real job was to dig up and draw pictures of American Indian artifacts that dated back almost a thousand years for the Archeology Lab of the Museum of New Mexico. The “cultural artifact list,” as we called it, included bows and arrows, the pit houses we were unearthing, the flattish mortars and pestles for grinding corn called manos and metates, a few articles of clothing, pottery, sacred objects, and not too much more.

Compare that to today’s industrial city, which has an artifact list so long it would take hundreds of volumes to record it all—from our cell phones and iPods to the scores of appliances and tools in even a modestly equipped kitchen to furniture, computers, cars, stores, gas stations, earth moving equipment, and, well, you get the idea. To house and provide work and other spaces for the billions of people performing all the required tasks to produce, distribute, sell, and consume everything on the artifact list, we need cities. Any other form of organizing ourselves is simply too inefficient. Scattered among small, far-flung villages, we couldn’t assemble ourselves or the resources and tools necessary to fulfill our desires and expectations for stuff, including that which we need and that which we simply want.

(The thing to notice here is that the city has become the real engine of economic productivity. It brings the tools and the people who operate them closer together while providing order and channeling energy and materials though the built environment. Few other than Jane Jacobs have stressed this fact, which is too much to defend here in this short essay. But cite it I must and declare it is important.)

Is the city too big for what it produces? The answer is no. Large size is required for such a staggeringly large artifact list, but here is the essential point: the size of both is a disaster for the planet. Today’s city produces an artifact list that’s too large to be either sensible or healthy. That list ranges from the uplifting and practical to the ridiculous and destructive. So one of the most important decisions we can make is what to trim from that long menu of artifacts. Perhaps the first item we should scratch off the list is the automobile and its attendant infrastructure of massive highway systems and parking structures, not to mention carbon pollution.

It’s important to understand that shrinking the artifact list will result in cities of generally lower population. But it’s not enough merely to shrink the cities we have now—we need to rearrange the pieces. Today’s cities have dense urban centers ringed by ever-expanding, car-dependent, undifferentiated miles of inefficient urban and suburban sprawl. This structure is environmentally unsustainable and not conducive to pleasurable human activity. We need to break up that sprawl into a galaxy of cities, towns, and villages. Doing so would free up vast swaths of land for parks, agriculture, and wildlife, all of which would be easily accessible to people without having to resort to long, slow, polluting car rides.

Shrinking Cities

Welcome to healthy shrinking cities. We in America may be at the turning point in that wave of urban sprawl that began to engulf the countryside after the Second World War, powered by US government policies including subsidized single-family housing, massive highway-building and very cheap gasoline. Over the following decades, cities sloshed ever outward, in California for example, right up against the Sierra Foothills.

Now, though, that wave is reversing, with new development and population growth rolling back toward the centers. As a result of this reversal, the geographical footprint is shrinking. In the United States, this shift started, ironically, when the auto industry that built the cars that caused cities to swell into enormous space-consuming, highway-engorged giants in the first place dumped their workers for cheap labor overseas. It ushered in the age of the Rust Belt. That pattern has now been accelerated by the recent downturn. As oil prices inevitably rise, the trend will only be strengthened.

We’re familiar with the Detroits, Youngstowns, Flints, and other cities with big shrink. Now we also have cities in hot climates with too little water like Las Vegas, Phoenix, and those of the California Central Valley where sprawl is most pronounced and foreclosures are the worst in the country. In many cases, prices, population, and even buildings are all shrinking at once. Drive down some of the ghost suburbs and you see tumble weeds lodged in swinging screen doors, tall grasses taking over the yards and driveways, and spiderwebs filling dark corners.

The people in such cities understandably see these wrenching changes as a disaster that must be reversed. But I believe the shrinking city phenomenon offers an opportunity, not just to restore agriculture and natural lands that shouldn’t have been paved over in the first place, but a chance to build the right structures in the right places. It’s an opportunity to take advantage of all the things we’ve learned about cities in the past 60 years. I heard the great urban planner Paolo Soleri speak way back in 1965 about the benefits of a compact city designed for pedestrians—ie, humans—instead of sprawling, anonymous suburbs built for cars. I took his notions seriously.

The suburb/city with its inefficient, hugely distributed systems of pipes, wires, and pavement stretching toward the horizon was powered by artificially cheap energy. Geographically, it was much larger than a compact city made up of apartments and mixed-use buildings and neighborhoods with the same. And in the compact city, inhabitants could walk and bike to most destinations. In Soleri’s notion, the compact city was more like cities in Europe than those then spreading in a thin veneer across the United States. The car would be replaced as the primary mode of motorized transportation by the streetcar and the elevator.

If we could push the idea of the compact city of enormous variety—Soleri used the words “complexity” and “density”—the whole thing could run on something like a tenth of the energy, all renewable, and cover just a fifth of the land, compared to a sprawl city of the same population, making it possible to have nature and agriculture immediately next door. Just take the stairs or an elevator ride and you could walk or bike out in the country in a matter of a few short minutes.

Soleri’s words impressed me and, to this day, I remain convinced that restaurants, shops, promenades with fantastic views, and rooftop gardens could be connected by bridges between clusters of buildings several floors over the bustling pedestrian streets. It would be easy to build if we weren’t, instead, building cities that spread ever-outward with freeway interchanges costing hundreds of millions of dollars each, parking structures, and streets for cars. Bottom line: we need a geographically smaller city, but that is possible only if we shift from two-dimensional design dependent on cars to a more three-dimensional city designed around the human body. The new city needs to grow upwards, not outwards.

The differences between these two conceptions of what a city should be—the pedestrian-centered city versus the car-centered city—are profound. A car’s body is about 30 times heavier than a human’s, moves ten times as fast in normal operation, and takes up about 60 times the volume standing still—and much more when moving. Too big! The city designed around the car and its need for movement, fuel, and parking must be understood for the unhealthy—catastrophically unhealthy—alternative it is; the consequences of which are unfolding around us: climate change, a collapsing biosphere, and rapid resource exhaustion.

On the other hand, a city that is designed around the dimensions of the human body and its need for clean air and water as well as healthy food holds tremendous potential to improve the lives of its citizens as well as the health of the planet. Most environmentalists believe the best we can do with cities is to make them less damaging. In fact, well-designed cities could be net contributors to soil building and biodiversity, making them a benefit to people and nature simultaneously.

Understanding proportionality

So far, we’ve talked about cities mainly in the context of the United States. But, in fact, the fastest-growing metropolises are elsewhere. They are also being built around the automobile—and, as such, they are a growing disaster for our planet. China is promoting cars and building streets and highways as fast as it can and India is also building a car culture. Brazil is cutting down forests and converting land used for food to land used for fuel while drilling in the Atlantic at levels three times deeper than the BP well that blew out. The Russian government recently announced that it is buying 2.5 million acres for low-density, car-dependent, single-family housing to instill the value of home ownership in its people. Add up the populations of these four countries and you get approximately 2.7 billion people. That’s about nine times the number people who live in the United States. The rapidly accelerating trend toward car-dependent cities in these four countries is one of the most dangerous trends of our times.

But there is another way. Rather than repeat the mistakes of the West on a grander scale, the new cities that are rising and the older ones that are evolving can be structured on a new, more sustainable model, one that doesn’t depend on the gasoline engine. Here’s how I think it would look:

Urban centers would become denser. They would serve as residential centers as well as work and retail centers. Meanwhile, the acres and acres of asphalt parking lots, lawns, and low, land-consuming strip malls spread out over vast acreage would give way to farm- and parkland. Features like creeks would work their way back into the landscape. Downtowns would be revitalized with new investment and would enhance the work and residential lives of the inhabitants. Those downtowns would no longer be strangled with space-wasting freeway interchanges. There would be no need for the immense volume of sheltered space that is now wasted on the parking of cars.

Elsewhere, major district centers would become small cities or towns in their own right and neighborhood centers would become villages of varying sizes, each with its own character. Buildings would, on average, be higher, houses would be replaced by apartments and cars by bicycles, walkable streets, streetcars, and elevators. Pleasurable and beautiful places like rooftop gardens and restaurants, multi-story solar greenhouses and bridges with spectacular views connecting buildings would predominate, along with renewable energy and closed-in organic agriculture. It would be the start of a new green economy.

Such cities would be places to further the ecological health of human society and whatever we mean by “nature” on this planet. But, equally important, such cities would be places to grow and develop ever more “human” humans. Thus we help further both ecological health and our own evolution at the same time.

How big could these cities be? Only if we start building them will we begin to learn the answer.

  • There was a time when cities where designed by great architects and decorated by great artists. Visit my blog and you will see all the buildings and monuments built in late XIX century in Buenos Aires.

    Best regards, Andres

  • Tad Salyards

    The author is absolutely correct, but there are very few politicians in America who are willing to verbalize the absolute destruction (environmentally, economically, and socially) that the “age of the automobile” has caused. At some point after ww2, the right to live where we want and drive as much as we want has been assumed by Americans as “the American way.”

    I had an interesting conversation with a “tea party” member some months ago when he was grousing about the subsidization of Amtrack. I reminded him that the automobile is, hands down, the most heavily subsidized transportation method in the country. He honestly believed that the gas tax was paying in full to continue the pavement of paradise. So much ignorance abounds.

  • Daniel Beaudry

    I totally agree with this vision.
    However it is difficult to imagine that the day will come that the majority of the population will even phantom such a fantastic utopia. We have been talking of saving energy and the planet for more than 20 years but when you drive on the highway and see these speeding gas guzzlers by hundreds, you realize that behaviour did not move a micrometer
    Daniel Beaudry

  • Mercedes Aragones

    I agree, except for the ones that live in cities built in areas where earthquakes are frequent and very destructive, like our Mexico City. Will we have to move from our location? It was chosen in 1325 by the Aztecs for its altitude and, as a result, temperate good weather all year round, in the 19th degree of latitude North. Like us, many cities have the same problem. Let´s think about it…


    A thought provoking article. I am however somewhat skeptical about the vertically rising cities. My concerns are:
    1. Vertical cities will consume enormous amount of steel which is scarce. It is also a mineral like oil.
    2. Natural calamities like earthquakes can play havoc with the concentrated population.
    3. Other health issues will prop up like dearth of oxygen at ground level within the city due to density of population scarcity of greenary and open spaces in city centers.
    4. Electricity will still be required and that too at a higher rate for ellevators, illumination, airconditioning and other electric needs. This will consume oil and gas.
    5. In town planning for such highly dense cities, all factories and production facilities will have to be in industrial zones outside cities requiring again transportation, commutation and broad roads to cope with such heavy one-way traffic.

    I think we will have to think drastically different. Following are some points to ponder:

    a. Roof-top crops and plantations under flyovers.
    b. More research on sunlight, water and wind energies.
    c. Breaking of city centers into sub-centers and spreading them accross the city and suburb.
    d. Breaking industrial zones according to types of industries and spreading them in different areas near and around the cities.
    c. Scientific research in finding substitutes for mortar, cement and steel.
    d. Research on modes of transportation and fuel efficient cars.
    e. Research on substituting water for fuel.
    f. Research on re-cycling CO2.

    Best regards

  • Daniel Fangorn

    Vertical cities do require more steel and concrete, but they permit vastly more land to be left undeveloped. Additionally, three storey buildings can be constructed from wood and are significantly more dense and energy efficient than individual houses.

    If you want to protect the population from natural disasters you have to abolish all cities and put families back on their own individual farms.

    Clustering too many tall buildings together doesn’t deprive people of oxygen, but it does create heat islands that affect the weather.
    Clustering too many cars together DOES in fact affect our ability to breathe.

    Condensing many small buildings into one large building almost always reduces per capita energy consumption, even when elevators are required. Air conditioning is an interesting topic because it could be argued that humans should not be living anywhere that’s too hot or too cold, but without a massive reduction in world population coupled with a breakdown of national borders humans will continue to live in places where their per capita energy consumption is unsustainable.

    There is no reason why some industry could not be integrated into the fabric of a city. In that case most workers would be pedestrians. For those industries that are incompatible with urban living, public transit should be sufficient.


    God gave us a pair of feet. That is the only means of transportation to which any of us has a right. Every other means of locomotion, be it a bicycle, horse or BMW, is a privilege with inherent costs. Unfortunately many people see such transportation options as rights instead of privileges and many of the costs are either hidden from us or, in the case of environmental change, not even counted by modern society.

    If the earth had a balance sheet very few industries would be profitable, but we as a species would probably be just as happy and the world around us would be in much better shape.

  • Valeria Vincent Sancisi

    To begin to think in terms of ‘scale’ is an adjustment for Americans, and the ways of doing anything. It’s always been rather way thinking.

    The shift, is to reframe sustainable systems- whether they be cities, buildings, business models (that’s a biggie) into the ultimate limitless goals of perpetual gain. It will outlive pursuing gains that are not sustainable.

    Reframing the conversation is the key. The rest is design. Let’s get to work!

  • j.a.simon

    Brilliant,incisive,practical,boldand truthfull,holds promise for the future.


  • Donald Johnson

    From a design and economics perspective I am with you, but are we not ignoring politics? There is no, absolutely no, tolerance anywhere in the US for increasing density. I know this from experience – I recall one project in a reasonably affluent, educated and environmentally conscious city neighborhood of one and two family homes, in which we proposed to replace a vacant hall and shuttered gas station on a major street with 3-4 stories of apartments over shops, in a very nice design. From the uproar you would have expected that we were proposing the opposite, and we were frequently asked “can’t it just be a park?” Unless you tackle public perceptions and preferences for low density living this is (respectfully) nothing more than designers sharing what-if scenarios with each other.

  • Jeyaseelan J

    Cities are an economic necessity. It epitomizes the essence of the fundamental economic principles of division of labor and economies of scale on the one hand and in the inevitable societal necessity of collective survival.

    One way to understand the economic role of cities would be to imagine two alternative scenarios. One in which a few thousand workers travel every day from sparsely populated country sides to equally widely dispersed offices for their jobs. Another where an equal number of office workers live in cities and travel to offices located within a few kilometers of their residences.

    The main difference between the two situations is the fact that in the latter case the office workers end up creating a number of viable business opportunities that in turn create more jobs. It could be bus company, a few restaurants, salons and whole array of services for which they would create a viable level of demand. The first case does not provide any such business/job opportunities at all.

    No doubt, transport, water, sanitation and environment act as major constraints on the optimal expansion of cities. Once these infrastructure services are well planned and managed efficiently, there could be no limit to the optimal expansion of cities. Of course in countries like the US the economics of urban living might necessitate spatial shrinking even while population numbers of such cities keep increasing.

    Of course, transportation is key constraint. Most cities are forcing people to forget the healthy habit of walking. People are not actually averse to walking as much as they fear walking on the roads. I particularly like the idea of elevated walkways interconnecting buildings. Perhaps the time has come for cities to leave the ground level and under ground for motorized transport and create walk around facilities above ground which are connected to the ground level with lifts and escalators.

    There is no economic or societal substitute for cities, even if the early migrants to cities would like to turn cities in to countrysides.

  • Valeria Vincent Sancisi, LEED AP

    I was on a plane to Germany from San Francisco a few years ago, and overheard a group of business men who were going to tour German towns, so that they could redesign American malls, especially the covered ones into open air town centers to help revive them.
    The market spoke, people want to gather together, like in in small scale European Towns.
    As different values emerge, how cities, towns, work, will reflect those values.
    How these values are presented is key. There is the return on investment, and the quality of life; make them the same.

  • Cities for people? The Netherlands is an excellent action research field. Cars are not predominant, rather bikes and pedestrians. How does that come? A clear intention of its leaders to put the citizen into the front of service.

    JaneJacobs with some general thoughts that are lasting over decades (perhaps centuries)

  • bdelapena

    i agree with the need for denser cities and that people must come first, but I disagree that this means skyscrapers and sky bridges. If we learned anything from Jane Jacobs, it’s that the street matters. Towers in the park (very Corbu, btw) is not the only way to achieve density.

  • The exurban sprawl model of US metro development is fast declining primarily because of economic, not environmental factors. See my recent chapter, “The Death of Sprawl”: In contrast, many core urban areas and public-transit served suburban towns have performed relatively well. As oil prices (and supplies) remain volatile, these areas will continue to be even more attractive and accessible to investors, residents and businesses. Our work has focused on demonstrating these trends in developing nations, including China and India, where the new urban development model must emphasize higher densities, multi-modal transportation, resource efficiency (water, food, materials), or these countries too will experience the exurban ghost towns that are emerging in California, Nevada, Arizona and Florida.

    Warren Karlenzig
    Common Current (

  • Nils

    It’s possible to build high without steel and concrete. Worlds tallest wooden building, 20 stories high, is planned in Norway:

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