Effects of Urban Containment on Housing Prices and Landowner Behavior

Smart growth has moved from the domain of policy analysts into more general acceptance. It is championed by national leaders such as Vice President Al Gore, governors (Parris Glendening of Maryland), urban mayors (William A. Johnson of Rochester, New York), non-governmental organizations (National Trust for Historic Preservation), and the private sector (Urban Land Institute). Voters in many California cities, including Sacramento, Santa Barbara, Irvine and Davis, and in numerous suburbs around San Francisco have approved urban growth boundaries (UGB) as one type of intervention to contain sprawl development.

Urban containment policies are not limited to environmentally active communities in California, Oregon or Colorado, or booming economies in states such as Florida, however. Lexington, Kentucky, observed the 40th anniversary of its urban growth boundary last year, and Sioux Falls, South Dakota, has had a containment boundary for many years. This kind of broad-based popular support for smart growth policies is more than simply a growth management fad and is likely to increase, particularly as long as the national economic expansion continues. Indeed, urban containment appears to be building a kind of momentum as a land use policy that has not been seen since the Supreme Court’s sanctioning of zoning in Ambler Realty Co. vs. Euclid, Ohio.

Urban containment planning has two basic purposes: (1) to promote compact, contiguous, and accessible development provided with efficient public services; and (2) to preserve open space, agricultural land and environmentally sensitive areas that are not currently suitable for development. Urban containment consists of drawing a line around an urban area within which development is encouraged, often with density bonuses or minimum density requirements, to accommodate projected growth over a specified future time period, typically ten to twenty years. Land outside the boundary is generally restricted to resource uses and to very low-density residential development by limiting the extension of utilities, wastewater services and other infrastructure.

Intuitively, however, this sort of land regulation appears to be a double-edged sword. On the one hand, measures aimed at reducing traffic congestion or infrastructure costs, or improving the aesthetic quality of urban areas, are appealing. On the other hand, measures that are seen to limit land supply and potentially cause housing prices to increase are unappealing, particularly to those seeking to expand the stock of affordable housing.

To explore the implications of these two faces of urban containment as smart growth policy, the Lincoln Institute and the Fannie Mae Foundation convened a group of scholars and practitioners for a symposium in Cambridge last February. The economists, planners and other researchers in attendance discussed the existing literature on urban containment and identified questions for future research that could inform policy making in this dynamic area of land regulation.

Housing Price Effects

Housing costs reflect the price of land, the price of the house and the value of amenities. Urban containment policies change housing costs for two reasons. First, land prices change when land supply is altered. Second, if urban containment increases the value of the amenity package associated with a house, then that, too, will cause a change in house prices. Much of the discussion at the symposium centered around these two theoretically distinct aspects of the housing price problem.

Most economic literature assessing urban containment argues that it raises land and housing prices principally by constraining the supply of land and/or by failing to accommodate new demand for serviced land. But, others argue that urban containment systems, when coupled with increased densities within the growth boundary, should not adversely affect supply and, indeed, should generate benefits to residents. This latter view shifts the focus away from the microeconomic theory of price determination to housing economics, which introduces the concept that house prices capitalize the value of neighborhood amenities.

For example, the increased densities within an urban growth boundary can make it practical to extend or enhance existing public transit, thus yielding greater accessibility. In addition, increases in densities can result in lower costs to provide urban services by the public sector. Similarly, higher neighborhood densities can lead to more interactions with neighbors and more “eyes on the streets,” which, in turn, can translate into lower crime rates. Finally, if urban containment is successful in preserving open spaces, house values in neighborhoods near the preserved open space should also rise.

All of these benefits can be counted among the amenities that give value to a house and are ultimately capitalized in its value, even while the land supply restriction can also put pressure on house prices. In truth, both factors may be at work, and we still have much to learn about their impacts. Furthermore, some of these internalized benefits may have different values for households at different income levels.

A comparison of Atlanta, Georgia, and Portland, Oregon, both suggests of these sorts of benefits and points to areas for future research to answer these questions more comprehensively (see Table 1). During the first half of the 1990s, Portland experienced a large increase in housing prices (approximately 60 percent compared to almost 20 percent in Atlanta, in nominal terms). Between the mid-1980s and the mid-1990s, homeownership rates in Portland increased by nearly 5 percent while Atlanta’s rate remained virtually unchanged. Finally, perceptions of improved house quality were greater among Portland residents than those in Atlanta. In both metropolitan areas and in both time periods, the proportion of household income spent on housing was virtually the same, suggesting that income growth in Portland exceeded that in Atlanta. However, it is difficult to conclude definitively that increases in house quality in Portland were due to enhanced amenities conferred on households by changes in land regulation, rather than to rising incomes.

Although urban containment policies may stabilize the supply of land, they usually increase the supply of development opportunities. Such policies are typically accompanied by “upzoning” whereby land zoned formerly at one level of development intensity is changed to allow for a higher density. One strategy to increase densities is to infill and redevelop (or “refill”) urban areas at higher than extant levels through the adoption of “minimum intensity” zoning. We do not know the subsequent effect of such policies on house prices, and we know even less about their effect on household budgets and disposable income. For example, higher housing prices may simply reflect capitalization of more efficient development patterns that reduce expenditures in other parts of the household budget.

It is possible, however, that current and future homeowners will benefit directly from these sorts of capitalized savings. For example, location-efficient mortgages, a lending instrument being tested in a few markets, allow lenders to extend mortgages to households based on a higher mortgage-to-income ratio. The rationale for altering the income eligibility is that, in comparison to suburban households, urban households can substitute walking and public transit for automobile payments, including both capital costs and operating expenses. Thus, disposable income is effectively increased as non-housing expenditures decline. Current experiments with the location-efficient mortgage are underway in Chicago’s northside neighborhoods and in central Seattle. If default rates for these loans are similar to those for traditional mortgages, we may see greater adoption of this instrument in appropriate submarkets.

Other savings that may accrue to urban homeowners as a result of containment policies are lower taxes due to lower capital costs or increases in supplemental income if higher densities are achieved through the addition of accessory apartments in existing houses.

Landowner Behavior Implications

The imposition of urban containment policies and changes in density are also likely to result in changed expectations of landowners. Therefore, an additional consideration for researchers, which the symposium participants confronted, is the role of containment in affecting the nature of landowner behavior with respect to land acquisition and land development.

In an environment of a relatively inexhaustible supply of land, speculation can be reasonably efficient while the competition to sell land keeps prices low. The end result may be that housing prices will not be affected materially. However, when supply is constrained, even if upzoning increases development capacity, the number of players in the land market can fall and cartels may form. Furthermore, an assumption of urban containment policies is that undeveloped land inside the boundary will come on-line in sufficient amounts and at appropriate times to sustain development. There is no research into this, however. Will owners of land, knowing they hold an oligopolistic position in the land market, delay its sale to get a higher price?

Until now, in our studies of urban land markets, we have lived with the assumption of relatively inexhaustible (i.e., elastic) land supply. Urban containment policies can change that premise by making land an exhaustible commodity, resulting in the problem of dual predictability. On one hand, developers are given more certainty in whether and how they develop land; on the other hand, landowners know that land supply will become exhaustible and therefore they may be enticed to become speculators, in their own right. Will local governments reward those willing to develop vacant or underused parcels with higher densities to offset others who delay sale? Certainly, a land tax is expected to limit this sort of behavior. Can other changes in the tax regime encourage development within the UGB? For all of these reasons, we have much to learn about the effect of urban containment on landowner and speculative behavior.

Summary Observations

The symposium participants spent more time on the economic issues related to urban containment than on environmental concerns. However, some material was presented that suggested significant environmental benefits as a result of urban containment. Table 2 presents additional comparisons of Portland and Atlanta between the mid-1980s and the mid-1990s. While vehicle miles traveled increased in both places, Portland experienced little change (2 percent) whereas Atlanta experienced a significant increase (17 percent). At the same time, Portland’s average commute times fell, air quality improved, and per capita energy consumption declined.

All of these indicators suggest that Portland is different from Atlanta in meaningful ways. Furthermore, typical behavior by individuals in each of these metropolitan areas is presumed to be different. We should attempt to find out the degree to which growth containment policies account for these behavioral differences and whether there are other policies that may also play important roles in affecting the economic and environmental dynamics of metropolitan regions. For example, the problem of housing affordability remains a serious concern in most cities, whether with or without urban containment boundaries.

Urban containment creates an entirely new regime in urban planning and development decision making, offering research challenges because of the difficulties in developing methodologies that can tease out complex interactions and frame the results in a manner that can advance both public and private interests. The Lincoln Institute, the Fannie Mae Foundation and the U.S. Department of Housing and Urban Development are among a growing number of research entities interested in pursuing these challenges.

Arthur C. Nelson is professor of city planning, urban design and public policy at the Georgia Institute of Technology in Atlanta. He organized the seminar referenced in this article and has researched and written extensively on this topic.