Marilyn Montgomery

Comparing Disproportionate Exposure to Acute and Chronic Pollution Risks: A Case Study in Houston, Texas

While environmental justice (EJ) research in the United States has focused primarily on the social distribution of chronic pollution risks, previous empirical studies have not analyzed disparities in exposure to both chronic (long-term) and acute (short-term) pollution in the same study area. Our article addresses this limitation though a case study that compares social inequities in exposure to chronic and acute pollution risks in the Greater Houston Metropolitan Statistical Area, Texas. The study integrates estimates of chronic cancer risk associated with ambient exposure to hazardous air pollutants from the Environmental Protection Agencys National-Scale Air Toxics Assessment (2005), hazardous chemical accidents from the National Response Centers Emergency Response Notification System (2007-2011), and sociodemographic characteristics from the American Community Survey (2007-2011). Statistical analyses are based on descriptive comparisons, bivariate correlations, and locally derived spatial regression models that account for spatial dependence in the data. Results indicate that neighborhoods with a higher percentage of Hispanic residents, lower percentage of homeowners, and higher income inequality are facing significantly greater exposure to both chronic and acute pollution risks. The non-Hispanic black percentage is significantly higher in neighborhoods with greater chronic cancer risk, but lower in areas exposed to acute pollution events. Households isolated by language--those highly likely to face evacuation problems during an actual chemical disaster--tend to reside in areas facing significantly greater exposure to high-impact acute events. Our findings emphasize the growing need to examine social inequities in exposure to both chronic and acute pollution risks in future EJ research and policy.

Social and Spatial Inequities in Exposure to Flood Risk in Miami, Florida

AbstractAlthough environmental justice (EJ) research in the United States has traditionally focused on technological hazards such as air pollution or hazardous waste, the adverse and unequal impacts of Hurricane Katrina have prompted researchers to examine the EJ implications of natural events such as hurricanes and floods. This paper contributes to this emerging literature on EJ and social vulnerability to natural hazards by analyzing racial/ethnic and socioeconomic inequities in the distribution of flood risk exposure in the Miami Metropolitan Statistical Area (MSA), Florida—one of the most hurricane-prone areas in the world and one of the most ethnically and socioeconomically diverse MSAs in the United States. Although previous studies have relied exclusively on the 100-year floodplain to assess the spatial extent of flood exposure, this study makes a systematic distinction between different types of flood zones on the basis of both the probability (100-year versus 500-year versus low/no risk) of flood...

Downscaling Environmental Justice Analysis: Determinants of Household-Level Hazardous Air Pollutant Exposure in Greater Houston

Environmental justice (EJ) research has relied on ecological analyses of coarse-scale areal units to determine whether particular populations are disproportionately burdened by toxic risks. This article advances quantitative EJ research by (1) examining whether statistical associations found for geographic units translate to relationships at the household level; (2) testing competing explanations for distributional injustices never before investigated; (3) examining adverse health implications of hazardous air pollutant (HAP) exposures; and (4) applying an underutilized statistical technique appropriate for geographically clustered data. Our study makes these advances by using generalized estimating equations to examine distributive environmental inequities in the Greater Houston (Texas) metropolitan area, based on primary household-level survey data and census block–level cancer risk estimates of HAP exposure from the U.S. Environmental Protection Agency. In addition to main statistical effects, interaction effects are modeled to examine whether minority racial or ethnic status modifies the effects of other variables on HAP cancer risk. In terms of main effects, Hispanic and black status as well as the desire to live close to public transit exhibit robust associations with HAP cancer risk. Interaction results reveal that homeownership and homophily (i.e., the desire to live among people culturally similar to oneself) are associated with higher HAP cancer risk among Hispanics and blacks but with lower risk among whites. Disproportionate risks experienced by Hispanics and blacks are attributable neither to dampened risk perceptions nor the desire to live close to work. These findings have implications for EJ research and practice in Greater Houston and elsewhere.

Assessing the environmental justice consequences of flood risk: a case study in Miami, Florida

Recent environmental justice (EJ) research has emphasized the need to analyze social inequities in the distribution of natural hazards such as hurricanes and floods, and examine intra-ethnic diversity in patterns of EJ. This study contributes to the emerging EJ scholarship on exposure to flooding and ethnic heterogeneity by analyzing the racial/ethnic and socioeconomic characteristics of the population residing within coastal and inland flood risk zones in the Miami Metropolitan Statistical Area (MSA), Florida—one of the most ethnically diverse MSAs in the U.S. and one of the most hurricane-prone areas in the world. We examine coastal and inland flood zones separately because of differences in amenities such as water views and beach access. Instead of treating the Hispanic population as a homogenous group, we disaggregate the Hispanic category into relevant country-of-origin subgroups. Inequities in flood risk exposure are statistically analyzed using socio-demographic variables derived from the 2010 U.S. Census and 2007–2011 American Community Survey estimates, and 100-year flood risk zones from the Federal Emergency Management Agency (FEMA). Social vulnerability is represented with two neighborhood deprivation indices called economic insecurity and instability. We also analyze the presence of seasonal/vacation homes and proximity to public beach access sites as water-related amenity variables. Logistic regression modeling is utilized to estimate the odds of neighborhood-level exposure to coastal and inland 100-year flood risks. Results indicate that neighborhoods with greater percentages of non-Hispanic Blacks, Hispanics, and Hispanic subgroups of Colombians and Puerto Ricans are exposed to inland flood risks in areas without water-related amenities, while Mexicans are inequitably exposed to coastal flood risks. Our findings demonstrate the importance of treating coastal and inland flood risks separately while controlling for water-related amenities, and recognizing intra-ethnic diversity within the Hispanic category to obtain a more comprehensive assessment of the social distribution of flood risks.

Assessing Current and Future Freshwater Flood Risk from North Atlantic Tropical Cyclones via Insurance Claims

The most recent decades have witnessed record breaking losses associated with U.S. landfalling tropical cyclones (TCs). Flood-related damages represent a large portion of these losses, and although storm surge is typically the main focus in the media and of warnings, much of the TC flood losses are instead freshwater-driven, often extending far inland from the landfall locations. Despite this actuality, knowledge of TC freshwater flood risk is still limited. Here we provide for the first time a comprehensive assessment of the TC freshwater flood risk from the full set of all significant flood events associated with U.S. landfalling TCs from 2001 to 2014. We find that the areas impacted by freshwater flooding are nearly equally divided between coastal and inland areas. We determine the statistical relationship between physical hazard and residential economic impact at a community level for the entire country. These results allow us to assess the potential future changes in TC freshwater flood risk due to changing climate pattern and urbanization in a more heavily populated U.S. Findings have important implications for flood risk management, insurance and resilience.

Hazard Characteristics and Patterns of Environmental Injustice: Household-Level Determinants of Environmental Risk in Miami, Florida

Limited systematic comparative knowledge exists about patterns of environmental injustices in exposure to varied natural and technological hazards. To address this gap, we examine how hazard characteristics (i.e., punctuated event/suddenness of onset, frequency/magnitude, and divisibility) influence relationships between race/ethnicity, nativity, socioeconomic status (SES), older age, housing tenure, and residential hazard exposure. Sociodemographic data come from a random sample survey of 602 residents of the tricounty Miami Metropolitan Statistical Area (Florida). Hazard exposure was measured using spatial data from the Federal Emergency Management Agency, the National Air Toxics Assessment, and the Emergency Response Notification System. We specified generalized estimating equations (GEEs)-which account for sociospatial clustering-predicting 100-year flood risk, acute chemical accidental releases, and chronic cancer risk from air toxics from all and on-road mobile sources. We found that for punctuated, sudden onset events, some socially advantaged people were significantly at risk. Racial/ethnic minority variables were significant predictors of greater exposure to the three technological hazards, while higher SES was associated with 100-year flood risk exposure. Black and foreign-born Hispanic residents, and white and U.S.-born Hispanic residents, shared nearly identical risk profiles. Results demonstrate the complexities found in human-hazard associations and the roles of hazard characteristics in shaping disparate risk patterns.

Pricing Storm Surge Risks in Florida: Implications for Determining Flood Insurance Premiums and Evaluating Mitigation Measures: Pricing Storm Surge Risks in Florida

The National Flood Insurance Program (NFIP) has been criticized for inaccurate flood hazard maps and premiums that are not risk based. We employ granular storm surge data comprised of five different event probabilities with associated flood elevations to calculate surge risk-based premiums for homes in Pensacola, Florida, which we compare with NFIP premiums that are based on flood risk data with only one event probability (1% annual chance floods). We demonstrate how more granular flood risk data used for calculating risk-based insurance premiums should be part of the NFIP mapping and rate-setting processes. We then examine three different sea-level rise (SLR) scenarios specific to Pensacola from the National Oceanic and Atmospheric Administration (NOAA), and assess surge risk-based premiums out to 2100. We analyze the cost effectiveness of elevating homes to mitigate surge risks when costs of elevation are one lump upfront sum, and when costs are spread over 30 years via low-interest mitigation loans. Benefits are the avoided future losses from surge risks going out to 2100 with the three different SLR scenarios. Findings show that it is cost effective to elevate high-value homes with low first-floor elevations in the most risky surge zones. Spreading costs of elevation with 30-year loans should be directed at low-income households to address affordability concerns. Alternative flood mitigation actions, such as wet floodproofing and elevating electrical and plumbing utilities, should be considered in instances where elevation is not cost effective.