How dense can we be?

Two years ago, geographer Paul Sutton was studying satellite images of metropolitan Denver when something unexpected caught his eye. As he had anticipated, the glowing nighttime lights clearly delineated the city and its suburbs. But in the foothills west of Denver, he noticed faint but extensive twinkles — a dispersed civilization just beyond the city.

"I said, ‘Wow, that’s where I live. I didn’t think there were that many of us out there,’ " remembers Sutton, who works at the University of Denver.

Sutton’s home is in the Conifer-Evergreen area, 20 to 25 miles from Denver. Around 40,000 people live in this unincorporated region of Jefferson County, among rolling hills covered by ponderosa pines. They live on large lots and, for the most part, in big homes, connected to Denver by miles and miles of coiled country lanes and massive, four-lane freeways.

Like suburbia, the Conifer-Evergreen area has rush hours, local newspapers and one of Colorado’s busiest grocery stores. But its semi-rural setting makes it different. It’s not suburbia; it’s "exurbia.

Suburban neighborhoods typically have from two to six households per acre. But even suburbs are far more compact than the sprawling exurbs, which tend to begin at one home per acre, and go on up to 35 acres or more. These are the ranchettes, the mini-estates, and the horse properties. These are the homes with John Deere tractors in the driveways and mule deer bounding in the backyard.

Exurban living is built on inherent contradictions. The country homes are always tethered to the better-paying jobs and more diverse culture of a city or town. "Far enough away from the metroplex to avoid traffic snarls, crowds and the 24/7 city lifestyle, yet close enough to enjoy world-class sports, shopping and cultural activities in the Mile High City," crows one real estate firm about its development in the foothills west of Denver.

Sutton’s home is a slice of that exurban paradise. It’s just a 25- to 30-minute drive (unless it’s rush hour) from his office near downtown Denver. It’s 3,000 feet higher than Denver, and in many ways a world apart. There’s a mosaic of aspen and pine trees, sometimes fox and deer, and not least, a sense of independence and isolation. From his deck, Sutton could not smack a golf ball far enough to hit one of his neighbors’ houses.

His neighborhood defines exurbia in other ways, too. It has neither streetlights nor sidewalks. Each home has its own water well and septic tank. And every home has at least one car, often several: Exurbia absolutely depends upon driving, sometimes hundreds of miles a day.

Before he bought his place, Sutton looked at city homes, but found the choices too costly, too shabby, or too suburban-bland. In the exurbs, he found everything he wanted. He’s close enough to civilization to get Domino’s pizza and flowers delivered to his front door, but far enough from his neighbors to have privacy. "It’s like Edward Abbey said, ‘If you can’t pee off your porch, you live too close to town,’ " he says.

What’s not to like about exurbia? Well, actually, plenty, as many environmentalists, land-use planners and geographers — including Sutton himself — have come to realize. "It’s really scary how much land it could consume," he says.

Encouraged by cheap gasoline and compliant county and state governments, and pushed by rapid population growth, exurban development is chewing away at the Western landscape. The region’s towns, cities and suburbs are also growing at breakneck speeds. But in the unincorporated semi-rural areas, the population is expanding even more rapidly.

"This type of uncontrolled, large-lot residential development is the great Pac-Man, gobbling up the West," says Rich McClintock, director of the Livable Communities Support Center, a program of Denver-based Civic Results, an anti-sprawl group.

If current development trends continue, in fact, some fear that it may one day be necessary to go to Kansas to find wide-open spaces.

The exurban explosion is about as subtle as a brick landing on a windshield. A few simple statistics about metropolitan Denver tell the story: Ninety-two percent of the population lives in relatively close quarters on two-thirds of the area’s land; the other 8 percent of the population sprawls across the remaining third. If the area attracts another 1.2 million residents in the next 25 years, as demographers predict, and if all those new residents live at exurban densities, the metro area will more than triple from its existing 750 square miles, to about half the size of Yellowstone National Park.

That’s just one metro area. What’s scary is how much population growth lies ahead in the Intermountain West, and how much wealth — a key enabler of exurban development — is headed this way. Exurban development already has a huge footprint on the land, and it’s getting bigger by the day.

The term "exurbia" was coined in 1955 by Auguste Spectorsky, an editor at Playboy magazine, in a book he wrote about wealthy neighborhoods beyond the immediate suburbs of New York City. Geographers began focusing on exurbia about a decade ago, and the term has become common in the press during the past two years, loosely referring to the newer, more affluent rings of suburbs that are no longer connected to traditional downtowns. New York Times columnist David Brooks argued that Democrats lost the national election last November because, unlike Republicans, they didn’t even know where exurbia is, much less understand it.

True exurbia, with its large lots and separation from job centers, has existed since the early 20th century. Many of today’s inner-ring suburbs were originally home to mini-farms serviced by trains from the cities, and to weekend retreats at the end of long dirt lanes. After World War II, those exurbs turned into suburbs, as cars and improved roads made longer commutes possible. The exurbs, in turn, spread farther outward.

In Colorado over the last 40 years, an average 144,000 acres of farmland has been lost annually to other uses, according to the U.S. Census of Agriculture. Exurban development is largely responsible. Between 1960 and 1990, Colorado’s unincorporated semi-rural areas gained population three times more rapidly than its towns and cities. In the 1990s, large-lot construction rose sharply in Jefferson, Douglas and other counties along Colorado’s urbanized Front Range.

This development trend is playing out across the West. Most often, it’s within an hour to an hour-and-a-half of cities, but the same patterns can be found around small towns, particularly near resorts and national parks.

Exurban development is exploding in California’s Sierra Nevada and flanking the coast cities from San Diego to San Luis Obispo. Near Bozeman, Mont., buyers of large lots are nuzzling up to nature — and contesting the turf of grizzly bears (HCN, 5/10/99: In Montana: The view from the ranchette). The eastern portal to Utah’s Zion National Park is being carved up into larger lots, putting residents close to heaven but a long way from the grocery store (HCN, 9/29/97: 'Greens' bulldoze a conservation effort). In Durango, Colo., last winter, a newspaper advertised "20 acres next to the national forest only 20 minutes from downtown."

In Durango, as in Conifer, the jobs may be relatively close. But in Western ski towns, the jobs may actually be in New York City, or in Washington, D.C., as is the case for Vice President Dick Cheney, a large-lot owner in Wyoming’s Jackson Hole. Near Park City, Utah, a resident stuntwoman keeps her Los Angeles cell phone to give callers the illusion of her proximity to Hollywood. In fact, at just 35 minutes from the Salt Lake City airport, she’s fudging the truth only slightly.

This large-lot, out-in-the-country phenomenon is happening even well away from ski resorts or national parks. Randy Brady, a real estate broker in Cañon City, Colo., says some of the exurbanites in his neighborhood commute 30 and 40 miles to city jobs in Colorado Springs and Pueblo. But most are retirees and even locals who commute to jobs in the state and federal prisons of Cañon City and Penrose. Brady has watched in amazement as the ranches of his youth have been chopped into 35-acre ranchettes. "It’s hard to fathom how fast it has happened," he says.

The surge of exurban development in the last decade has startled academics, environmental activists and even local governments.

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