Mapping the Future of Urban Sprawl

I'm going to show you a bunch of maps," David Theobald tells the undergraduates packed into the small lecture hall. "Don't get caught up writing down the numbers. I want you to get a couple of key points."

As a rule, maps and the numbers behind them are a matter of some consequence to Theobald, a geography professor at Colorado State University — the way a Bible matters to a preacher or an oxygen tank to an astronaut. His courses tend to be highly technical forays into the spatial analysis of public lands and entire ecosystems. Today, though, he's pinch-hitting for a colleague who teaches a class on parks and protected areas, and he doesn't want to cause a stampede for the door with a gruesome display of mathematics.

His lecture may be titled "Protected Areas From a Conservation Landscape Perspective," but there's nothing tweedy about Theobald or his approach to the subject. Wearing huaraches, white pants, a busy yellow shirt and a winning smile, he jumps into his PowerPoint presentation with zest. The first image is of the students' regular professor, Peter Newman, holding a sign endorsing their visitor: "He knows his stuff." That's followed by a picture of Newman holding a second sign: "You in the back pipe down."

After the laughter, those in the back pipe down, and Theobald proceeds to demonstrate that he does indeed know his stuff. On the big screen, he shows how geographic information system (GIS) tools — basically, a computerized approach to combining geographic features with other data — led to better protection of bird habitat in Hawaii. He talks about different ways of analyzing "wild" or "developed" areas and points out that calling popular recreation destinations like Rocky Mountain National Park "protected" may be misleading.

"One year I rode my bike over Trail Ridge Road on the Fourth of July," he recalls. "It was stupid. I sucked fumes all the way."

He hands out atlases and challenges the students to find local parks. Many of the maps, he adds, are incorrect, outdated or incomplete — yet we make policy decisions on bad information all the time. His frustration with antiquated data led to the CoMAP project (short for Colorado Ownership Management and Protection), an ambitious effort to inventory and map open space across the state, funded by Great Outdoors Colorado and other agencies. He asks how many of them have seen the enormous map in the hall outside Pete Newman's office — a 45-square-foot, high-resolution display that highlights the nearly 30 million acres of the state that have some degree of federal, state, local or private protection against development.

The students stare at him blankly. Theobald is nonplussed. "Doesn't anybody know where your professor's office is?" he asks.

No hands go up. Nobody seems to have a clue. Theobald shrugs. It's early in the semester. But still.

"Look around," he says. "Get to know your environment."

Theobald has spent much of his 43 years getting to know his environment. Aside from a master's degree earned in California, much of his studying and teaching has been in Colorado, including field work across the state for a variety of research projects. Along the way, he's figured out new approaches to charting the state's rapid population growth and development patterns and the impact they have on wildlife and the land itself.

His projects stretch from fine-grain, parcel-by-parcel studies of buildout effects in a single county to large-scale calculations of shifting land use across the West. He's chronicled the upside of conservation easements and the downside of sprawl. Much of his work revolves around what's known in ecology circles as "the wildland-urban interface," those flash points where new subdivisions creep into formerly natural areas. In particular, he's known for his expertise in the relentless march of exurbia — formerly rural areas that have been carved up into residential parcels of 35 acres or less.

Theobald considers the spread of exurbia to be one of the greatest threats to the state's natural resources. Low-density development not only takes more land to house fewer people, he points out, but it produces disproportionate traffic, pollution and other problems. In places such as Douglas and Elbert counties, ranches are turned into ranchettes, increasing commute times and fragmenting wildlife habitat. In the mountains, pricey new McMansions introduce more human activity to wildfire zones and increase demand for more roads and services. Colorado's wide-open spaces are now being devoured at a pace three times the national average, and Theobald expects the amount of land devoted to exurban development to double in the next two decades.

Increasingly sophisticated computer programs have allowed researchers to document changes in the natural environment of the West like never before; they've also opened the door to modeling future scenarios, projecting what the land will look like in a generation or two by crunching critical data about population shifts, zoning laws, watersheds, wildlife migration corridors, and so on. "We've gotten pretty good at depicting the demise of habitat and telling that story," Theobald says. "Now the question is, 'What should we do? What are our options?' That's where a lot of GIS work is going."