Chang Yi
Urban sprawl is a ubiquitous form of our built environment in metropolitan America, which planners as well as the public have recognized as being a product of household choices vis-à-vis land use and transportation. Local zoning regimes have been perceived as the guardians of such “market outcomes,” translating preferences for suburban living into their corresponding realities. In light of this perception, advocates for compact developments cast their arguments for planning transit- and pedestrian-friendly neighborhoods in terms of the negative consequences of sprawl versus travel behavior benefits of the proposed alternative developments (e.g., reduced automobile use). In Zoned Out, Levine takes a critical stance toward such a framework, pointing out that it is groundless and inadequate. The author claims that the negative consequences of sprawl are not an outcome of market failure, but rather of planning failure, pronounced in exclusive zoning that prohibits high-density and mixed-use developments. Levine states, “Despite its pervasiveness and academic pedigree, the reinterpretation of municipal land-use regulation as a kind of market force is unwarranted.” The tendency to equate zoning with market preferences dates back to the 1920s. Since the Village of Euclid v. Ambler Realty case established the constitutionality of zoning, Levine argues, the legal community has granted zoning a special exemption from judicial scrutiny with regard to its public purposes. Although zoning was based on police power state regulation of land use, judges have accepted the notion that zoning is a collective property right inherent to municipalities. This reasoning, prevalent in the judicial community, has resulted in the favorable treatment of zoning and in municipal governments being granted prerogative on local land use matters. “Viewing land-use regulation as a property right held by the municipality serves to legitimate parochial ends as long as these are the preferences of the locals.”
When zoning is interpreted in this way, urban sprawl is seen as a natural outcome of unrestrained household choices driven by real estate markets, and the promotion of compact developments becomes equivalent to a planning intervention that acts as a restraint on the market process. In such a case, establishing the transportation benefits of compact developments is assumed to be a necessary condition to legitimize governmental intervention (e.g., the subsidizing of compact developments). Zoned Out offers an alternative perspective: Levine argues that sprawl is not a market outcome, but rather a consequence of municipal zoning favorable to low-density built environments. Planning for dense urban forms, therefore, is not an intervention; instead, it rather diversifies choice sets in the housing market by allowing such development options. Thus, Levine argues, there is no burden of proof necessary to justify such a widening of the market horizon; “the first order of business is the elimination of regulatory obstacles to compact development, a search for the travel behavior benefits that would justify governmental intervention is poorly matched with the policy task at hand.”
In Zoned Out, Levine supports this idea with empirical evidence drawn from his research in Atlanta and Boston. His study indicates that Atlanta households with preferences for transit- and pedestrian-oriented developments are less likely to be able to satisfy their desires than Boston households. On the other hand, given the diverse sorts of neighborhoods found in Boston, Bostonian households have greater opportunities to act on their transportation and land use preferences. That is, the supply of alternative developments is not meeting the demand in Atlanta’s sprawled metropolitan area. In essence, the study contends that zoning is not an instrument for ensuring market efficiency, but rather is a form of regulation that distorts market forces, since it prevents households from matching their preferences to actual choices. Then, Levine’s argument to “eliminate regulatory obstacles” is justified.
These findings shed new light on the problem of selection bias in transportation research. For more than two decades, in transportation research circles, isolating the pure effects of urban forms on travel from self-selection has been a difficult issue for researchers. For instance, to determine whether a transit-oriented neighborhood elicits greater transit ridership, researchers seek to separate the impact on travel behavior of average individuals from individuals who moved to the area because of their preference for taking public transit. Levine suggests that “the view that self-selection is inherently a source of bias to be measured and eliminated presupposes that these market preferences for transit- and pedestrian-oriented neighborhoods have already been satisfied.” As Levine finds in the study on Atlanta and Boston, this is not the case. He claims that the bias is, in fact, an evidence of the travel benefits of dense and mixed-use urban forms, since that bias (households moving into transit-oriented neighborhoods to satisfy their travel preferences) represents a fulfillment of the previously unmet demands of residential choices. To land use and transportation research communities, this discussion provides new provoking arguments and insights.
Overall, Levine offers a critical understanding of the nature of zoning, in particular the ways in which it prevents alternative developments, and presents a new perspective for future research. Yet, the book raises some questions. Implicitly, Levine makes the fundamental assumption that expanding market choices for individuals does not require proving travel behavior benefits. Nonetheless, proving such benefits still matters when encouraging scarce development forms whose societal impact is still not clearly identified. What if an unconstrained creation of high-density and mixed land use developments generates negative by-products? In the last chapter of his book, Levine describes the state planning mandate in Oregon as an exemplary solution for fostering alternative developments. However, Oregon’s statewide growth management scheme drove up Portland’s housing prices as well as population density within its urban growth boundary. Though research on this issue is inconclusive, it would appear that due to the lack of affordable housing in the central city, low-income households have been displaced to more peripheral areas with lower land prices. This may have resulted in longer commutes to the city center, while causing heavier traffic congestion within the inner city. At this juncture, when the impact of high-density and mixed-use developments is uncertain, research efforts to establish the travel behavior benefits of alternative developments are indeed meaningful.
Notwithstanding this criticism, Zoned Out, taken as a whole, successfully challenges the commonly accepted belief regarding the role of zoning in shaping metropolitan America. The implications for future research are substantial. By reading Levine’s work, transportation planners and researchers will be exposed to a new and intelligent perspective with which to form strong arguments for justifying smart growth