jump to navigation

Methodology

Mardi Gras on Bourbon Street

Mardi Gras on Bourbon Street

Hypothesis

We hypothesize there is a direct relationship between the physical form of the built environment and damage caused by a disaster event. Similarly, a direct relationship should exist between the form of human social organization within the built environment with the ability of populations to recover after such an event.

Research Question

Our research asks the question “What physical characteristics and usage patterns of New Orleans’ built environment had an effect on damage and recovery for local communities?”

Research Design

Keeping in mind Masten and Obradovic’s (2008) argument that “all disasters are local” and that specific local characteristics of the built environment in New Orleans are needed to measure damage and recovery, we searched available disaster and New Orleans literature to identify such localized characteristics.

Data Sources

Our data sources include the U.S. Census Bureau’s Decennial Census 2000 SF1 and SF3, Census 2000 Structural and Facility Characteristics of All Housing Units, Census 2000 Geographic Comparison Tables, 2005 and 2006 Zip Code Business Patterns, Greater New Orleans Community Data Center Households Receiving Mail 07/05 – 12/08, FEMA Average Water Level and Total Real Property Damage, and ThinkNOLA.com Building and Demolitions Permits. The use of each of these sources is found below:

Measures from the Literature

The following factors were identified in the literature as measurements for the physical characteristics of neighborhoods, the density of the built environment and the population living in it –  including locally contextualized factors for the city of New Orleans as suggested by Masten and Obradovic (2008). The hypotheses raised in the literature is summarized in italics below, followed by a list of the data measures being used to test each hypothesis.

Higher density of human population creates a dense mass of social networks (strong and weak ties) that should increase ability to recover (Wallace and Wallace, 2008).

Social structures of organization (strong and weak ties) that aid in recovery after a disaster cannot foster in a physical environment that cannot fundamentally support them.

As density increases, the potential for catastrophic losses from disaster events increases (Mileti, 1999).

Building codes were not modernized until the 1950’s, but despite these new codes, it was not until the 1980’s that inspectors received training in floodplain management policies and began to enforce” regulations (Colton, 2005, 160).

The more healthy, productive adults in a household that has weathered a disaster event, the greater the chance for recovery (Morrow, 1999).

The older and more stable a neighborhood is, the larger and more resourceful social networks (strong and weak ties) can become (Wallace and Wallace, 2008).

Apartment dwellers and renters will have a harder time recovering because they are at the mercy of their landlords willingness to invest capital. The situation becomes even more complicated with condominiums and loft apartment buildings as mutual owners may make conflicting decisions about recovery(Comerio, 1998).

The loss of a significant portion of the business sector in any neighborhood greatly reduces the ability of the local residents to recover from damages due to the loss of local economic ties.

Minimal infrastructure damage permits victims to at least keep their jobs and be able to focus on housing recovery” instead of searching for employment (Comerio, 1998, page).

“When both housing and commercial sectors are heavily damaged, the real loss of the population and an [economic] base makes recovery issues quite” complicated (Comerio, 1998, page).

Between 1950 and 1975, the built up area of metropolitan New Orleans doubled in size as the “tissue of suburbia” exploded into the recently drained swamps. Such developments are raising serious questions about the wisdom, much less the safety, of new development in New Orleans (Lewis, 2003, p.76-77). The question at hand is whether a high growth rate is beneficial or detrimental to the formation of social ties that will aid recovery efforts.

Most homes in the older sections were built with flooding in mind (Colton, 2005).

New Measures

While conducting our research, we began to examine the physical condition of housing units because more valuable homes may have one or all of three highly influential factors. Using the median value of occupied housing units for each zip code may function as a reliable proxy for the physical condition of properties when the disaster struck. Our hypothesis is that more expensive homes are valued for their quality, where a higher value may correlate with ability to minimize damage. Similarly, high value homes are more likely to carry flood insurance, a factor that should aid with recovery efforts post disaster. Third, a question concerning the presence of neighborhood social services (schools, police, fire stations, hospitals, garbage disposal, sewers, etc.) and their influence on recovery ability led to a search for a measure of social services by zip code. Calculating the median real estate taxes for each zip code as a percentage of home value supplies a proxy for the presence of social service institutions that need to be funded with property and school taxes.

Defining Damage and Recovery

Flooding Damage (NASA - DART)

Flooding Damage (NASA - DART)

Four measures of damage were gathered for each Zip Code in Orleans Parish.

Disaster Resistant Recovery Construction (volumezero.com)

Disaster Resistant Recovery Construction (volumezero.com)

Six measures of recovery were gathered from available data sources.

Testing

Pearson’s bivariate correlations were calculated across all variables to determine the strength and direction of any linear relationship between built environment and living arrangement factors identified by the literature, as well as measures of damage and recovery. Where needed, relationships to damage and recovery measures were controlled for other factors to remove any bias. This statistical test will help identify what factors of the built environment and its use have an impact, or lack there of, upon damage and recovery in New Orleans after hurricane Katrina.

Limitations

When studying density, it is desirable to acquire census data at the block group level instead of zip code. Block group factors would reveal more detailed spatial information about urban and human densities than what is available at zip code level. Unfortunately, most data sources available are do not provide information at the block group level. This is especially evident in the available measurements for damage and recovery. There was also an interest by the research group to expand our field of inquiry to include areas outside of Orleans Parish due to the extensive and widespread destruction that was caused by Hurricane Katrina. Again, however, limitations in the available data have reduced our ability to study the desired wider area. Consequently, for this research, only zip codes contained fully or partially within Orleans Parish were included.

Next (Findings) >>>

<<< Back to Literature Review

Advertisements
%d bloggers like this: