Samuel D. Brody

An Analysis of the Effects of Land Use and Land Cover on Flood Losses along the Gulf of Mexico Coast from 1999 to 2009

Major coastal flooding events over the last decade have led decision makers in the United States to favor structural engineering solutions as a means to protect vulnerable coastal communities from the adverse impacts of future storms. While a resistance-based approach to flood mitigation involving large-scale construction works may be a central component of a regional flood risk reduction strategy, it is equally important to consider the role of land use and land cover (LULC) patterns in protecting communities from floods. To date, little observational research has been conducted to quantify the effects of various LULC configurations on the amount of property damage occurring across coastal regions over time. In response, we statistically examine the impacts of LULC on observed flood damage across 2,692 watersheds bordering the Gulf of Mexico. Specifically, we analyze statistical linear regression models to isolate the influence of multiple LULC categories on over 372,000 insured flood losses claimed under the National Flood Insurance Program per year from 2001 to 2008. Results indicate that percent increase in palustrine wetlands is the equivalent to, on average, a

Measuring the impact of mitigation activities on flood loss reduction at the parcel level: the case of the clear creek watershed on the upper Texas coast

13,975 reduction in insured flood losses per year, per watershed. These and other results provide important insights to policy makers on how protecting specific types of LULC can help reduce adverse impacts to local communities.

Understanding the motivations of coastal residents to voluntarily purchase federal flood insurance

As property damage from flooding continues to increase, particularly in coastal areas, the adoption of strategies to mitigate these losses has never been more important to protecting the health and safety of coastal communities. Both structural and non-structural flood mitigation activities are being considered to buffer the adverse consequences of building structures in areas exposed to flood risk. However, little research has been conducted on the effectiveness of flood mitigation practices, particularly non-structural approaches at the parcel level. Our study addresses this lack of critical knowledge by examining the effect of mitigation activities adopted under the FEMA community rating system on insured property losses across multiple communities within the Clear Creek watershed located just south of Houston, TX and adjacent to Galveston Bay. Specifically, we statistically identify the degree to which various mitigation strategies adopted by a community reduce flood loss claims among 9,555 parcels from 1999 to 2009. Results indicate that several mitigation policies adopted at the community level result in significant savings in property damage for homeowners in the Clear Creek watershed.

Household adjustment to flood risk: a survey of coastal residents in Texas and Florida, United States

Federally-backed flood insurance is the primary mechanism by which residents in the United States (US) prepare for and recover from floods. While there is a growing literature on the general uptake of flood insurance, little work has been done to address the factors motivating residents to voluntarily buy and maintain federally-based insurance policies. We address this issue by conducting a survey of coastal residents in four localities in Texas and Florida. Based on survey responses, we quantitatively examine the factors influencing whether residents located outside of the 100-year floodplain obtain insurance policies when it is not required. Using two-sample t-tests and binary logistic regression analysis to control for multiple contextual and psychological variables, we statistically isolate the factors contributing most to the decision to purchase insurance. Our findings indicate that a resident located outside the 100-year floodplain who has voluntarily purchased federal flood insurance can be characterized, on average, as more highly educated, living in relatively expensive homes, and a long-time resident who thinks about flood hazard relatively infrequently but who, nonetheless, thinks flood insurance is relatively affordable. Unexpectedly, the physical proximity of a respondent to flood hazard areas makes little or no discernible difference in the decision to obtain flood insurance.

Economic impacts of storm surge and the cost-benefit analysis of a coastal spine as the surge mitigation strategy in Houston-Galveston area in the USA

Individual households have increasingly borne responsibility for reducing the adverse impacts of flooding on their property. Little observational research has been conducted, however, at the household level to examine the major factors contributing to the selection of a particular household adjustment. This study addresses the issue by evaluating statistically the factors influencing the adoption of various household flood hazard adjustments. The results indicate that respondents with higher-value homes or longer housing tenure are more likely to adopt structural and expensive techniques. In addition, the information source and the Community Rating System (CRS) score for the jurisdiction where the household is located have a significant bearing on household adjustment. In contrast, proximity to risk zones and risk perception yield somewhat mixed results or behave counter to assumptions in the literature. The study findings provide insights that will be of value to governments and decision-makers interested in encouraging homeowners to take protective action given increasing flood risk.

Ecological indicators of flood risk along the Gulf of Mexico

Rapid population growth, urbanization, and concentration of valuable assets and strategic infrastructure in coastal regions make coastal inundation, flooding, and storm surge national problems for many countries, including thexa0United States of America (USA). Enhancing coastal resilience is a complex problem and involves an integrated risk management approach, entailing both structural protection as well as other risk reduction strategies (e.g., building codes and ecosystem preservation). The former is an increasingly recognized mitigation option for densely populated areas and industrial hubs. Fully justifying benefits of costly flood defense structures is crucial, particularly when lack of funding and other institutional barriers make such projects easy targets for omission from or cuts to a budget. Justification usually requires a comprehensive cost-benefit analysis. This paper explores the economic feasibility of a coastal barrier, i.e., coastal spine, as a potential storm surge mitigation strategy to protect the Houston-Galveston metropolitan area of Texas, one of the most flood-prone and economically important regions in the USA. We provide an assessment of residential and chemical manufacturing plant and refinery exposure to multiple synthetic hurricane storm surge events by comparing losses with and without a coastal spine. While under all scenarios, benefits exceed engineering costs of a spine, our results indicate that the project feasibility largely hinges on accounting for industrial losses and resultant indirect and induced effects. As many regions and industrial hubs globally are designing adaptation and mitigation strategies to combat the consequences of extreme events, structural solution to surge mitigation maybe one of the few mitigation options for them. Unlike population and residential structures that can retreat and insure, these options are not viable for industrial plants that are resource-based. However, expertise and knowledge pertinent to surge barrier systems are relatively scarce as there are only handful of barriers around the world and they are all unique in engineering designs. As storm surge is becoming a threat for many coastal urban centers, one of the recommendations is to consolidate knowledge base and research across countries in order to foster knowledge exchange internationally. This will help identify concerns associated with existing barrier systems, pragmatic ways to improve them and will also aid the investment decision, engineering designs, and operational aspects of barriers in other parts of the world. Furthermore, forming regional research collaborations with developing countries at risk of storm surge and the sea level rise is vital to further facilitate knowledge spillover and exchange of expertise.