The problems of containment and the promise of planning

When the expansion of cities is constrained either by natural barriers, such as New Orleans, or by policy efforts to limit urban sprawl, development pressures in hazardous areas can markedly increase. As floodplains, steep slopes, earthquake fault zones, and other hazardous locations are converted to urban uses, the locality's vulnerability to hazard events increases as does the potential for serious losses of lives and property in natural disasters. The devastation of New Orleans from Hurricane Katrina is an extreme example of the phenomenon. But this threat can be neutralized if hazards are recognized in advance of exposure and appropriate counter-measures are adopted. The difficulty is that in the absence of state planning and hazard mitigation requirements, many localities ignore hazards in planning for and regulating urban development, as shown most recently by Steinberg and Burby (2002). New Orleans and Miami, Florida, provide excellent examples to evaluate the effects of adequate planning and preparation for cities in hazardous areas. New Orleans provides an example of what can occur in a city with severe constraints on buildable land and a lack of adequate public concern for hazards or urban development planning. In contrast, decisions made by policy makers in the State of Florida and by the Miami-Dade County Government illustrate how concern for hazard avoidance and resource protection can lead to policies that sharply limit development in flood-prone areas. To see if lessons revealed by these two cases could be replicated nationwide, we examine natural disasters and associated property damages in samples of metropolitan counties with varying degrees of containment brought about by policy decisions or natural conditions and with varying degrees of planning. And our findings are extremely telling. Metropolitan counties with either natural or policy containment experienced higher property losses in disasters when states left planning and development decisions wholly to local government discretion. Where states intervened and demanded that localities plan and manage development with hazard mitigation in mind, property losses are strikingly lower. These findings are significant for several reasons. Urban containment programs are proliferating throughout the United States as governments attempt to counter various adverse effects of urban sprawl (Nelson and Dawkins 2004). Yet with the exception of our earlier work on containment and hazards (Burby et al. 2001), planning literature makes virtually no mention of the potential for containment programs to foster unsafe development patterns. In fact, a recent paper published by the Brookings Institution (Pendall et al. 2002) enumerates a number of issues related to containment that the authors believe require the attention of planning scholars, but they make no mention of the potential for larger losses in disasters. This is a serious oversight. Natural hazards on average result in economic losses of approximately $26 billion per year in the United States (Mileti 1999), and, rather than decreasing, losses are increasing as urban development continues unabated in areas at risk (Cohn et al. 2001; Cutter 2001; Mileti 1999). Beginning with a description of urban containment programs and noting their increasing use in urban areas of the United States, this essay then explains the rationale for our hypotheses that containment, either by natural features or by sprawl-busting public policy, may accelerate development in hazardous areas and why state planning mandates may provide an antidote to this peril. This is followed by a discussion of the methods we employed to test these propositions and their limitations. The research findings follow in two stages. An examination of the experience of New Orleans shows that as the growth of the city came face to face with natural constraints, it chose to allow development in its very hazardous backswamps. The result, obviously, was quite poor. We contrast this with the growth of Miami and Dade County, where policy makers in the 1970s decided to limit the expansion of the city into low-lying hazardous areas by enacting an urban growth boundary. Following these case studies, we examine the magnitude of property losses in natural disasters in U.S. counties that have various degrees of natural containment and that have and have not adopted urban containment policies. This essay concludes with a discussion of the implications of our findings for state and local efforts to manage urban growth, and for federal disaster policy.