Some say urban sprawl is like pornography. Maybe you can't quite define it, but you know it when you see it.

One thing's certain: we can't talk much about it — urban sprawl, that is — without the subject of farmland coming up. Is urban sprawl depriving California of farmland?

Not quite, according to John Landis, professor of urban planning at the University of California, Berkeley, who measures where and at what density people reside in the Golden State. For him, the real question is not whether we are running out of land but how to arrange population growth on it.

For California as a whole, he says, more people are being accommodated on less land, and sprawl in terms of land utilization is actually declining. At the same time, he expects some shifts in how farmland is used to continue well into the future.

Landis spoke recently at Sonoma State University at Rohnert Park during a training session for journalists on land-use issues. The program was sponsored by the Foundation for American Communications and the Santa Rosa Press-Enterprise.

California population today is 34.5 million. By 2020, the forecast is about 45 million. By 2050, the head count is estimated to be 60 million, and another 50 years after that it could be 80 million to 90 million.

Average density in California urban centers now, he says, is 8 to 10 persons per acre, so with the additional 10 million people by the third decade of the century, he figures we will need another million acres of land for urban development.

‘Leapfrog development’

One manifestation of urban sprawl in the U.S. is “leapfrog development” or movement beyond cities into farmland or forests, often before adequate public services are in place.

“But leapfrogging is not as big a problem as we might think. We see it in a few places but not as before,” he says. The problem with leapfrogged developments is not so much their density but that they are too similar, too much like Los Angeles and failing to create the “sense of place” that has drawn people to the west for the past century.

Returning to land utilization, Landis says conventional wisdom about the rate of urban land diversion is that we are growing and running out of land, that sprawl uses more land per person. In the view of the Sierra Club and National Resource Defense Council, California is the most sprawling state in the country.

He counters with a computer-generated sprawl index, or growth in land development divided by growth in population. California, he says, calculates at 0.95. “Yes, California, as a whole, has been growing, but each person has been using slightly less land than the previous generation.” Even in Los Angeles and Orange counties, despite population growth there from 1972 to 1996, the “urban footprint” didn't enlarge appreciably.

In contrast, he adds, the average sprawl index rating for the lower tier of states was about 2 during the period of 1949 to 1992. Oklahoma, Tennessee, Arizona, Arkansas, and Maryland are among the most sprawling.

With the exception of Ventura County, Southern California's population grew, but each additional person used a little less land. Ventura County, he said, despite its policies to force growth in urban areas, is lagging behind the state average in land utilization.

The reason land use has been more efficient in California, he says, is because in the last 25 years we've shifted from “mom and pop” family-owned construction operations to well-capitalized, national developers.

They have built bigger two-story houses on smaller lots replacing the former pattern of single-family, single-story houses. Twenty-five years ago the average lot size was about 6,000 square feet, but today it is 4,500 square feet. Up and down the state, the population grows but needs less land per capita than before.

But some communities are a patchwork of development. Freestanding subdivisions tend to make farming near them more difficult, and “they break up the farms and resource areas for a huge impact on the landscape,” says Landis.

A prevailing notion is that development is leapfrogging into the countryside, resulting in more fragmented habitat for the state's 28.3 million acres of farmland. The American Farmland Trust and the California Department of Fish and Game, he notes, claim fragmented urban development is destroying the agricultural fabric of the Central Valley.

On the contrary, he argues, 95 percent of development is filling in two-mile-wide corridors flanking freeways, so that the total number of patches is diminishing.

Leapfrogging was the norm in the state in the 1940s through the 1960s, but since the l970s, as he puts it, “the footprints of development are getting larger but there are fewer footprints.” Landis says he believes it is largely a problem nowadays only for San Bernardino and Riverside counties.

Bad reputation

Leapfrogging has a bad reputation because it leaves land between urban centers “dead” to agriculture or practically any other use.

He prefers to define sprawl not as leapfrogging but as a “dense onion,” based on the layering of new developments outside the older. (And yes, allium fans, he admits the analogy is flawed, since onions do grow from their center.)

While the new developments are less intrusive for the countryside, people in the inner portions have less access to coveted open space. Each new layer also puts a strain on roads, utilities, and other infrastructure designed for the previous layers.

Landis reasons that growth in California over the past 25 years is because of land utilization, not leapfrogging. “Rising densities have saved a lot of open space. The Sierra and the coast are little more developed than they were a quarter-century ago. Texas, Florida, and North Carolina, on the other hand, are all much more developed than 25 years ago.”

By his analysis, California has accommodated population growth while leaving wilderness areas largely intact. The reason: the California Environmental Quality Act (CEQA) and its required public disclosure of impacts of development, including noise, traffic, and obstructions to view.

CEQA, he adds, “has given citizens much greater scope and leverage over developers, and that's meant developers cannot escape (dealing with the impacts of their projects) by jumping out into the countryside.”

According to Landis, outside of Southern California, there's more land in cultivation in the state today than four years ago, despite population growth.

That is not to say urban development has spared farmland. “In the Central Valley, the growth of Fresno, Bakersfield, and Stockton has taken over some of the best ag land on the valley floor.”

But, he adds, farmers have moved onto sloping ground, 3 to 4 percent grades, sometimes changing crops, sometimes not, and turned to low-volume irrigation. The mixture of crops, productivity, and value has increased. The only type of land that has declined in use is grazing land, largely because new farms have taken it over.

Again, except where urban sprawl has already occurred, the rest of the state is in no danger of running out of prime farmland. When a new subdivision takes over farmland, new farms spring up elsewhere.

“We can continue to do that, probably for 50 to 60 years,” Landis says, “without any serious negative effect.”

Other issues, such as hillside development, do exist, but he considers them local, not state-level, concerns.

e-mail: dan_bryant@intertec.com