American cities are different from European cities. Even lots of Americans who've never been to Europe realize this, although they may not understand exactly what the difference is. But what difference does it make?
Let's say you live in a typical European urban area. You're likely to live in an apartment in a multistory building. There's a good chance that there are shops in the ground floor of your building and of the buildings near you. Even if there aren't any shops in your building, there most likely are some within a block or two.
Let's say you live in a house, not an apartment, in a typical European urban area. In all likelihood, your house is quite small by American standards, and more importantly for the purposes of this discussion, so is your lot. Your next-door neighbor is probably very close to you, although there is probably some kind of arrangement to afford both of you some measure of privacy. And you probably don't live more than a couple of blocks off a main street or road that offers shops and other services. Since European cities don't enforce any kind of zoning, there's a reasonable chance that there are even shops on your street, a short distance away -- not only because there's no zoning, but because the smaller lots shorten distances (having to walk past twenty houses in Europe is not at all the same thing as having to walk past twenty houses in the U.S.).
Now let's say you live in a typical American urban area. There's a good chance that this means you live in an American suburb, and even if you don't, there's a good chance that you live in an urban neighborhood that is American-suburban in character. You probably live in a house, large by European standards, that sits on a lot that is positively huge by European standards. Also, since almost all American cities enforce zoning, you almost certainly live in an area that is zoned residential (and, probably, zoned single-family residential, meaning no apartment houses, or even duplexes, are permitted); that means that unless you live at or near the edge of your residential area, there are no shops or other services near you.
(An aside: Strangely enough, this is one reason European cities tend to have older architecture than American cities.
We are all familiar with the cycle that afflicts American cities. An area, let's call it Oakwoods, gets built, or "developed," all at once. The buildings, be they houses, office buildings, whatever, are popular because they're new. Then, as these buildings age and other, newer areas are constructed, Oakwoods becomes less popular. House prices and rents in Oakwoods decline; people with the means to do so leave Oakwoods for the newer areas. As Oakwoods continues to age, and even newer areas are constructed, its popularity declines further until it becomes, essentially, a slum, inhabited by people with no economic choice.
Why does this happen? Recall from my previous post Jacobs's observation that successful city neighborhoods tend to contain buildings of various ages. Because American districts usually are built all at once, they age together and arrive at the various points in this cycle in a depressingly predictable pattern. This happens not only because the buildings age together, but because they are also economically homogeneous; they tend to be occupied by people of pretty much the same station in life because they are the same age [newer buildings almost always cost more to occupy because the initial cost of construction has to be recouped].
In Europe, there tends to be much more mixing not only of types of use -- residential mixed with commercial, usually -- but also of building age. This mixes people of various financial situations together in the same city district. Consequently, there is less tendency to abandon an area that is "changing," a concept that generally does not apply in Europe anyway. Even if your financial situation changes, you can probably move within your area, to something either more or less expensive.
One obvious consequence of this is that European city districts tend not to decline precipitously in the way American ones do. But a less obvious one is that when districts contain buildings of various ages, there is much less reason to tear down the older buildings that make up part of the fabric of a district; instead, there is much more tendency to rehabilitate older buildings when the time comes.
So European cities tend to have retained more of their older buildings than American ones.)
We often tend to ascribe these differences to the respective urban cultures in both regions, and not think further about them. This is a serious mistake. These differences have two major consequences that it would behoove Americans to consider:
- Having shops nearby means you can walk to them.
- Having denser development means public transport can be provided at a reasonable cost.
Both of these differences contribute to four further consequences of the American type of city, based on one simple fact: If you can't walk or take transit to the things you need to get to, you have to drive a car. In fact, you end up driving a car to pretty much everything. (I am ignoring the bicycle option, which I myself use some of the time for commuting, because I realize most Americans aren't going to do it. They should, but they won't. One reason for this is that the sheer prevalence of the car makes American streets much less friendly to bicycles.) Which means:
- Automobile use is the primary driver, no pun intended, of our dependence on oil, and specifically on foreign oil. This in turn drives our foreign policy in directions that generally don't make a lot of sense, to put it mildly.
- Driving an automobile everywhere means that you get entirely too little exercise. This sedentary life is a major contributor to the high cost of health care in this country.
- Driving an automobile everywhere means you are pouring huge amounts of greenhouse gases into the environment, making global warming much worse.
- Having an automobile, and driving it everywhere, is appallingly expensive.
This is why I think the way our cities are built is the primary problem the United States faces. It urgently needs to be solved, but we have to realize that solving it means we will have to fundamentally change the way we live.
Sunday, September 6, 2009
Wednesday, April 9, 2008
Urban Land Use
What do we mean by "land use"? The term refers to how we build on the land we have at our disposal. There are two different primary aspects of land use: density and type of use.
American land use generally differs from land use in European countries in both of these aspects. In the U.S., building has generally been done at considerably lower densities than what is typical in Europe; and the U.S. has tended to segregate land uses very strictly (through zoning laws), a concept largely unknown in Europe. Leaving aside the historical and cultural reasons for this, which are very complex, let's look at what effect this has on the urban landscape.
Consider the typical American developed area. It consists of numerous freestanding buildings, most of them only one story tall, each with its own parking area. The buildings in any given area are used for the same purpose -- they may be residential, or commercial, or industrial, but rarely does one find these kinds of buildings intermixed; and because the buildings are mostly one-story, or occasionally two-story, it's not practical to combine these uses in one building.
Now consider the typical European developed area. It consists of buildings in close proximity to each other. These buildings are three to five stories tall. Parallel on-street parking -- if that -- is the only kind of parking provided. While industrial uses are often not included in such an area, one finds residential and commercial (shops and offices) uses mixed together. Buildings frequently have shops on the ground floor and apartments on the upper floors.
Jane Jacobs, in her seminal work The Death and Life of Great American Cities, set forth the following criteria for functional urban neighborhoods.
1. The district, and indeed as many of its internal parts as possible, must serve more than one primary function; preferably more than two. These must insure the presence of people who go outdoors on different schedules and are in the place for different purposes, but who are able to use many facilities in common.
2. Most blocks must be short; that is, streets and opportunities to turn corners must be frequent.
3. The district must mingle buildings that vary in age and condition, including a good proportion of old ones.
4. The district must have a sufficiently dense concentration of people, for whatever purpose they may be there. This includes people there because of residence.
European urban districts generally meet and exceed Jacobs's criteria (1) and (4). Some European cities, and some areas within the same city, do better than others at (2) and (3); many European cities have maintained old street networks that include some long blocks, and some cities have redeveloped some of their districts, resulting in substantial areas of buildings that are all the same age. But a European city or metropolitan area typically combines areas of significant density with areas left undeveloped.
However, few American urban districts meet any of these criteria. Most of them serve only one primary function, have very long blocks (especially in suburban areas), have mostly new buildings (the great majority of the U.S. built environment is post-WWII), and don't concentrate people in sufficient numbers. The development is a thin smear that covers all, or nearly all, the land available.
What are "sufficient numbers"? At the risk of oversimplifying, I'll just say that Jacobs emphasizes looking at density in terms of the number of residential units per net residential acre (the latter refers to the amount of land given over to residential use, whether it is built on or left open) and operating on the assumption that individual units are not overcrowded. (If they are, the district is in trouble regardless of other factors.) Here is a passage from chapter 11 of the book:
Very low densities, six dwellings or fewer to the net acre, can make out well in suburbs. Lots at such densities average, say, 70 by 100 feet or more. Some suburban densities go higher, of course; lots at ten dwellings to the acre average just under, say, 50 by 90 feet, which is a squeeze for suburban living but, with clever site planning, good design and genuine suburban location, can yield a suburb or a reasonable facsimile.
Between ten and twenty dwellings to the acre yields a kind of semisuburb, consisting either of detached or two-family houses on handkerchief plots, or else of generously sized row houses with relatively generous yards or greens. These arrangements, although they are apt to be dull, can be viable and safe if they are secluded from city life; for example if they lie toward the outer edges of a big city. They will not generate city liveliness or public life -- their populations are too thin -- nor will they help maintain city sidewalk safety. But there may be no need for them to do so.
However, densities of this kind ringing a city are a bad long-term bet, destined to become gray area. As the city continues to grow, the character that makes these semisuburbs reasonably attractive and functional is lost. As they are engulfed and embedded deep in a city, they lose, of course, their former geographical closeness to true suburbs or countryside. But more than that, they lose their protection from people who do not "fit in" to each other's private lives economically or socially, and they lose their aloofness from the peculiar problems of city life. Swallowed into a city and its ordinary problems, they possess no city vitality to contend with these problems.
...
Above these semisuburban densities, the realities of city life can seldom be evaded, even for a short time.
In cities (which you will recall have not the self-containment of towns), densities at twenty dwellings to the acre and above mean that many people who live near each other geographically are strangers to one another and always will be strangers. Not only that, but strangers from elsewhere find it easy to be present because other neighborhoods of this same density or higher are close by.
Rather abruptly, once a semisuburban density is exceeded, or a suburban location engulfed, an entirely different kind of city settlement exists -- a settlement which now has different kinds of everyday jobs to handle and a need for different ways of handling them, a settlement which lacks assets of one kind but potentially has assets of another kind. From this point on, a city settlement needs city vitality and city diversity.
Unfortunately, however, densities high enough to bring with them innate city problems are not by any means necessarily high enough to do their share in producing city liveliness, safety, convenience and interest. And so, between the point where semisuburban character and function are lost, and the point at which lively diversity and public life can arise, lies a range of big-city densities that I shall call "in-between" densities. They are fit neither for suburban life nor for city life. They are fit, generally, for nothing but trouble.
Jacobs goes on to say that in cities, the point at which city diversity and safety begin to be possible seems to lie around 100 dwellings per net residential acre. She emphasizes, however, that this point can vary from city to city, and that the estimate of 100 dwellings/acre probably applies only when the other three conditions for functional urban districts are met. In general, she says, the figure will probably be found to be higher.
It's important for me to note here that Jacobs reached her conclusions by studying and directly observing actual city neighborhoods, something that planners up to that time (the book was published in 1961) had been curiously reluctant to do, preferring to dream up theories of how cities should work -- many of which haunt the urban planning profession to this day -- instead of paying attention to how cities actually work.
So what? you may be saying. In future posts, I'll talk about the effects each kind of development has.
American land use generally differs from land use in European countries in both of these aspects. In the U.S., building has generally been done at considerably lower densities than what is typical in Europe; and the U.S. has tended to segregate land uses very strictly (through zoning laws), a concept largely unknown in Europe. Leaving aside the historical and cultural reasons for this, which are very complex, let's look at what effect this has on the urban landscape.
Consider the typical American developed area. It consists of numerous freestanding buildings, most of them only one story tall, each with its own parking area. The buildings in any given area are used for the same purpose -- they may be residential, or commercial, or industrial, but rarely does one find these kinds of buildings intermixed; and because the buildings are mostly one-story, or occasionally two-story, it's not practical to combine these uses in one building.
Now consider the typical European developed area. It consists of buildings in close proximity to each other. These buildings are three to five stories tall. Parallel on-street parking -- if that -- is the only kind of parking provided. While industrial uses are often not included in such an area, one finds residential and commercial (shops and offices) uses mixed together. Buildings frequently have shops on the ground floor and apartments on the upper floors.
Jane Jacobs, in her seminal work The Death and Life of Great American Cities, set forth the following criteria for functional urban neighborhoods.
1. The district, and indeed as many of its internal parts as possible, must serve more than one primary function; preferably more than two. These must insure the presence of people who go outdoors on different schedules and are in the place for different purposes, but who are able to use many facilities in common.
2. Most blocks must be short; that is, streets and opportunities to turn corners must be frequent.
3. The district must mingle buildings that vary in age and condition, including a good proportion of old ones.
4. The district must have a sufficiently dense concentration of people, for whatever purpose they may be there. This includes people there because of residence.
European urban districts generally meet and exceed Jacobs's criteria (1) and (4). Some European cities, and some areas within the same city, do better than others at (2) and (3); many European cities have maintained old street networks that include some long blocks, and some cities have redeveloped some of their districts, resulting in substantial areas of buildings that are all the same age. But a European city or metropolitan area typically combines areas of significant density with areas left undeveloped.
However, few American urban districts meet any of these criteria. Most of them serve only one primary function, have very long blocks (especially in suburban areas), have mostly new buildings (the great majority of the U.S. built environment is post-WWII), and don't concentrate people in sufficient numbers. The development is a thin smear that covers all, or nearly all, the land available.
What are "sufficient numbers"? At the risk of oversimplifying, I'll just say that Jacobs emphasizes looking at density in terms of the number of residential units per net residential acre (the latter refers to the amount of land given over to residential use, whether it is built on or left open) and operating on the assumption that individual units are not overcrowded. (If they are, the district is in trouble regardless of other factors.) Here is a passage from chapter 11 of the book:
Very low densities, six dwellings or fewer to the net acre, can make out well in suburbs. Lots at such densities average, say, 70 by 100 feet or more. Some suburban densities go higher, of course; lots at ten dwellings to the acre average just under, say, 50 by 90 feet, which is a squeeze for suburban living but, with clever site planning, good design and genuine suburban location, can yield a suburb or a reasonable facsimile.
Between ten and twenty dwellings to the acre yields a kind of semisuburb, consisting either of detached or two-family houses on handkerchief plots, or else of generously sized row houses with relatively generous yards or greens. These arrangements, although they are apt to be dull, can be viable and safe if they are secluded from city life; for example if they lie toward the outer edges of a big city. They will not generate city liveliness or public life -- their populations are too thin -- nor will they help maintain city sidewalk safety. But there may be no need for them to do so.
However, densities of this kind ringing a city are a bad long-term bet, destined to become gray area. As the city continues to grow, the character that makes these semisuburbs reasonably attractive and functional is lost. As they are engulfed and embedded deep in a city, they lose, of course, their former geographical closeness to true suburbs or countryside. But more than that, they lose their protection from people who do not "fit in" to each other's private lives economically or socially, and they lose their aloofness from the peculiar problems of city life. Swallowed into a city and its ordinary problems, they possess no city vitality to contend with these problems.
...
Above these semisuburban densities, the realities of city life can seldom be evaded, even for a short time.
In cities (which you will recall have not the self-containment of towns), densities at twenty dwellings to the acre and above mean that many people who live near each other geographically are strangers to one another and always will be strangers. Not only that, but strangers from elsewhere find it easy to be present because other neighborhoods of this same density or higher are close by.
Rather abruptly, once a semisuburban density is exceeded, or a suburban location engulfed, an entirely different kind of city settlement exists -- a settlement which now has different kinds of everyday jobs to handle and a need for different ways of handling them, a settlement which lacks assets of one kind but potentially has assets of another kind. From this point on, a city settlement needs city vitality and city diversity.
Unfortunately, however, densities high enough to bring with them innate city problems are not by any means necessarily high enough to do their share in producing city liveliness, safety, convenience and interest. And so, between the point where semisuburban character and function are lost, and the point at which lively diversity and public life can arise, lies a range of big-city densities that I shall call "in-between" densities. They are fit neither for suburban life nor for city life. They are fit, generally, for nothing but trouble.
Jacobs goes on to say that in cities, the point at which city diversity and safety begin to be possible seems to lie around 100 dwellings per net residential acre. She emphasizes, however, that this point can vary from city to city, and that the estimate of 100 dwellings/acre probably applies only when the other three conditions for functional urban districts are met. In general, she says, the figure will probably be found to be higher.
It's important for me to note here that Jacobs reached her conclusions by studying and directly observing actual city neighborhoods, something that planners up to that time (the book was published in 1961) had been curiously reluctant to do, preferring to dream up theories of how cities should work -- many of which haunt the urban planning profession to this day -- instead of paying attention to how cities actually work.
So what? you may be saying. In future posts, I'll talk about the effects each kind of development has.
Hi!
I've created this blog because I want to talk about some issues that bug me. Please note that many of these issues are U.S.-specific, although in many cases I will bring in perspectives from other countries that I am, more or less, familiar with. One main reason I'm focusing on U.S. issues is alluded to in the title of this blog: I think Americans, through no fault of their own, are usually too wrapped up in their (rather difficult) daily lives to lift their gaze and think about the larger issues that affect them.
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