Urban sprawl

Based on Wikipedia: Urban sprawl

Los Angeles is America's densest major city. Not New York. Not San Francisco. Los Angeles.

That fact stops most people cold. It certainly contradicts the usual story we tell about sprawl—that it's about low-density suburbs stretching endlessly into the desert, about car-dependent wastelands replacing walkable urban cores. But the Los Angeles paradox reveals something important: sprawl is not simply about density. It's about pattern, about separation, about how we've chosen to carve up the landscape into single-purpose zones that make walking and public transit nearly impossible.

What Sprawl Actually Means

The term "urban sprawl" carries an almost universally negative connotation. Few people proudly advocate for sprawl the way they might champion urban renewal or transit-oriented development. It has become a rallying cry, a shorthand for everything that went wrong with postwar American city planning.

But pinning down exactly what sprawl means proves surprisingly difficult. Researchers who study it acknowledge the term lacks precision. Some define it by residential density—the number of housing units per acre. Others focus on decentralization, measuring how far population has spread from a defined center. Still others emphasize discontinuity, what planners call "leapfrog development," where new subdivisions spring up with vacant land between them and existing development.

The British urbanist Frederic Osborn first used the phrase in a 1941 letter to the American urban theorist Lewis Mumford, lamenting the waste of agricultural land and natural landscape to suburban expansion. By 1955, The Times of London deployed it as a criticism of the city's outskirts. From the beginning, sprawl was an accusation, not a description.

Yet despite all the hand-wringing, sprawl has proven remarkably difficult to measure or prevent. Between 1982 and 2017, approximately 44 million acres of land in the United States was developed—an area roughly the size of Missouri. The Census Bureau classified about 2.6 percent of American land as urban by 2000, but the National Resources Inventory counted significantly more developed land because it includes rural development that technically cannot be called "urban" sprawl at all.

The Anatomy of Sprawl

If sprawl resists easy definition, certain patterns appear again and again in sprawling regions. Understanding these patterns helps explain why sprawl has proven so persistent despite decades of criticism.

The most fundamental characteristic is single-use zoning. Commercial areas stand apart from residential neighborhoods, which are separated from industrial zones, which are isolated from institutional uses like schools and hospitals. This segregation means that the places where people live, work, shop, and play are distant from one another. Walking between them is impractical. Public transit cannot efficiently serve such dispersed destinations. The automobile becomes not a convenience but a necessity.

Consider what this means in practice. Your home sits in a subdivision of houses. To reach the grocery store, you drive through residential streets to a collector road, which feeds into an arterial, which leads to a commercial strip. The grocery store shares a parking lot with a pharmacy, a dry cleaner, and a fast-food restaurant—but no homes. When you finish shopping, you reverse the journey. Every trip, no matter how minor, requires a car.

This pattern persists even in surprising places. The urbanist Peter Calthorpe coined the term "high-density sprawl" to describe China's urbanization. Chinese cities are filled with high-rise residential towers, which might seem like the opposite of American subdivisions. But these towers sit in "superblocks"—enormous single-use residential areas surrounded by massive arterial roads. Despite the vertical density, the horizontal pattern mimics American sprawl. Different functions are separated. Pedestrians find the environment hostile. The result is sprawl, just stacked vertically.

Jobs Follow People to the Periphery

Where people live, jobs eventually follow. This phenomenon, known as job sprawl, has reshaped American metropolitan areas over the past several decades.

Researchers at the Brookings Institution have tracked this transformation in detail. By one measure, any job located more than five miles from a city's central business district counts as sprawling. By more nuanced measurements that divide metropolitan areas into concentric rings, the pattern becomes clear: employment in city centers is shrinking while the outer suburbs gain jobs.

A 2009 study examined the largest American metropolitan areas and found that only about 21 percent of jobs were located within three miles of the central business district. Another third sat between three and ten miles out. Nearly half—45 percent—were located between ten and thirty-five miles from downtown. Compared to just eight years earlier, these numbers showed a consistent shift outward.

This might sound like a natural evolution, but it creates a cruel irony. Many poor urban residents, often minorities, find themselves cut off from entry-level jobs that have migrated to the suburbs. Researchers call this "spatial mismatch." The jobs exist, and the workers exist, but they cannot reach each other. Public transit serves the old pattern—bringing suburban workers to downtown offices—not the new pattern of suburban employment. The result is that those who most need work are least able to access it.

Leapfrog Development and the Developer's Dilemma

One of sprawl's most distinctive patterns has an almost accidental quality to it. Leapfrog development occurs when new subdivisions spring up with undeveloped land between them and existing development. Instead of cities expanding smoothly outward, they grow in scattered patches.

This pattern is a twentieth and twenty-first century phenomenon, and it stems from how we build infrastructure. In earlier eras, local governments constructed streets and utilities, using their power of eminent domain to assemble land coherently. Today, developers typically must provide infrastructure as a condition of building. They must set aside land for roads, parks, and schools.

Private developers generally cannot force landowners to sell. They build on whatever parcels happen to be available when they want to develop. If the ideal parcel is not for sale, or the owner demands too high a price, the developer moves on to another location—often leapfrogging over perfectly suitable land to reach something available.

The result is a patchwork. New development appears here and there, separated by green belts of undeveloped land. Overall density plummets even as individual subdivisions might be moderately dense. The infrastructure costs per resident rise because roads and utilities must stretch further to reach scattered developments.

Why People Choose Sprawl

Given all this criticism, sprawl's persistence demands explanation. Why do people keep moving to sprawling suburbs?

One theory, colorfully called "flight from blight," emphasizes the push factors of urban life. High taxes, rising crime, failing schools, crumbling infrastructure—these problems drove middle-class families to seek safety and opportunity beyond city limits. The classic pattern of white flight in American cities fits this narrative, though the movement has never been exclusively white or exclusively American.

The landmark 1972 study "The Limits to Growth" listed the urban conditions that push wealthier residents outward: noise, pollution, crime, drug addiction, poverty, labor strikes, breakdown of social services. These were not merely preferences but rational responses to genuine problems.

But push factors only tell half the story. Pull factors matter too. As transportation improved—first with streetcars, then automobiles, then highways—living farther from work became feasible. Rising wages meant more people could afford houses with yards, garages, and space between neighbors. Sprawl, from this perspective, is simply what happens when more people can afford more housing.

The automobile deserves special attention here. American land use devotes vastly more space to parking than European cities. The United States might consider two to four houses per acre low-density, while the United Kingdom would still call eight to twelve houses per acre low-density. The difference is cars. When everyone drives, every destination needs parking. Parking lots spread buildings apart. Distances increase. Walking becomes impractical. More driving becomes necessary. The pattern reinforces itself.

The Agricultural Land We've Lost

Here is an uncomfortable irony: the most fertile agricultural land often lies immediately adjacent to cities. This is no coincidence. Cities historically grew where farming was productive enough to support a non-farming population. The relationship between city and countryside was symbiotic.

Sprawl consumes this productive land. The fields that once fed a city become the subdivisions that house its commuters. And American tax law actually encourages this conversion. A farmer who sells land to a developer can avoid capital gains taxes by using the proceeds to purchase agricultural land elsewhere—treating the transaction as a "like-kind exchange" rather than a sale. The tax break subsidizes sprawl at the expense of local food production.

In China, local governments have converted rural land to urban use in advance of actual demand, creating vacant land intended for future development. The sprawl exists before the people arrive, a ghost city waiting to be inhabited.

The Subdivision as Building Block

Drive through any American suburb and you will encounter the housing subdivision—large tracts of land consisting entirely of newly built residences. Developers sometimes call these villages, towns, or neighborhoods, but the urbanist firm Duany Plater-Zyberk notes that such terms are misleading. True villages and towns contain more than houses. They have shops, workplaces, civic buildings, gathering spaces. Subdivisions have none of these. They are purely residential, islands of housing in a sea of similar islands.

The architecture within subdivisions often exhibits remarkable uniformity. Tract housing—building the same design repeatedly—saves developers money. The result is streets where houses differ only in color or minor decorative details. The uniformity that critics mock as soul-crushing monotony represents, to developers, simple economics.

The street pattern matters too. Subdivisions typically feature curved roads and cul-de-sacs, dead-end streets that form circles or bulbs. These designs reduce through traffic, which residents value for safety and quiet. But they also mean that only a few points allow entry and exit. All trips must funnel through collector streets. A journey that would be short as the crow flies becomes long and circuitous by car—and walking remains essentially impossible.

The Lawn as Symbol

After World War Two, the residential lawn became nearly universal in American and Canadian suburbs. This was not inevitable. Lawns emerged from particular cultural and economic conditions.

Country clubs and golf courses in the early twentieth century helped popularize manicured grass as a status symbol. Returning veterans bought homes in new subdivisions where lawns came standard. Chemical companies promoted fertilizers and pesticides. Lawnmower manufacturers made maintenance feasible for individual homeowners. The lawn became an expected feature of suburban life.

These lawns consume water, require chemical inputs, demand weekly maintenance, and provide habitat for almost nothing. Yet they persist, expressing some deep American desire for a patch of controlled nature, a buffer between home and street, a marker of respectability and care.

Dense Cities That Still Sprawl

The Los Angeles paradox mentioned at the beginning deserves a closer look. How can America's densest major urban area also be a poster child for sprawl?

The answer lies in how we measure density. New York, San Francisco, and Chicago have extremely dense cores—Manhattan, for instance, packs more people per square mile than almost anywhere on Earth. But these cities also have extensive low-density peripheries. Eastern Suffolk County in the New York metropolitan area, or Marin County in the San Francisco Bay Area, are quite sparse. The average density of the entire metropolitan region reflects both the packed center and the empty edges.

Los Angeles lacks such extremes. It has no super-dense core comparable to Manhattan. But it also lacks truly sparse peripheries. Development spreads at moderate density across the entire region. The result is a higher average density than cities famous for their dense downtowns.

This pattern appears worldwide. Greater Mexico City, the Delhi National Capital Region, Beijing, and Greater Tokyo all sprawl despite relatively high density and mixed land uses. They sprawl in the sense of spreading outward, consuming ever more land, even as they remain far denser than American suburbs.

Detroit and the Shrinking City

Not all sprawl accompanies population growth. Detroit presents the troubling spectacle of a city that sprawled while losing population.

As residents fled Detroit's urban core for suburbs—and then fled the region entirely—the geographic footprint of the metropolitan area continued expanding. People spread out even as their total numbers declined. The city that once held nearly two million people now holds fewer than 640,000, but the developed land has not correspondingly shrunk.

This pattern appeared in European cities too, though without the infrastructure collapse that characterized Detroit. Between 1970 and 1990, Amsterdam, Brussels, Copenhagen, and several German cities all lost population while their urbanized areas expanded. People wanted more space even as their numbers declined. Sprawl proved compatible with demographic shrinkage.

The Politics of a Pejorative

Nobody runs for office promising more sprawl. The term carries such negative weight that advocating for it seems almost unthinkable. This makes sprawl unusual among political issues—few people defend it, yet it continues unabated.

The debate instead centers on competing visions of what cities should become. Smart growth advocates push for higher density, mixed uses, transit-oriented development, and urban infill. Property rights advocates resist restrictions on development. Environmentalists warn of habitat destruction and carbon emissions. Economists debate whether sprawl represents market preferences or market failures.

Some researchers argue that the pejorative nature of "sprawl" has distorted the debate. Defining sprawl by negative characteristics—low density is bad, single uses are bad, car dependence is bad—makes it impossible to have a neutral conversation about suburban development patterns. Perhaps some people genuinely prefer houses with yards, commutes by car, and separation from commercial activity. Calling their preferences "sprawl" frames the discussion before it begins.

And yet the environmental and fiscal costs remain. Sprawl consumes agricultural land. It generates automobile emissions. It requires expensive infrastructure—roads, water lines, sewers—that serves fewer people per mile than compact development. Residents of sprawling areas often pay lower taxes than they realize because their infrastructure was subsidized by growth itself; when growth stops, those costs come due.

What Comes Next

Understanding sprawl matters because we are still deciding what kind of places to build. Every zoning decision, every infrastructure investment, every tax incentive shapes the pattern of development for decades to come.

The good news is that sprawl is not destiny. Cities can change. Neighborhoods can densify. Transit can expand. Mixed-use development can replace single-use zoning. Whether these changes happen depends on political will, economic incentives, and the preferences of millions of individual households making decisions about where to live.

The Los Angeles paradox offers a strange hope. If America's most notoriously sprawling city is actually its densest, perhaps the relationship between sprawl and density is more flexible than we assume. Perhaps the pattern of development matters more than the simple numbers. Perhaps we can build places that feel spacious without consuming endless land, places where the car is an option rather than a requirement, places where the different functions of urban life sit close enough to walk between.

Or perhaps sprawl will continue as it has for eighty years, an outcome that almost no one explicitly chooses but that somehow keeps happening anyway. The forces that drive it—the desire for space, the economics of development, the shape of our tax code, the path dependence of our infrastructure—show no signs of disappearing. Understanding sprawl is the first step toward deciding whether we want to keep building it.