Revealing the Complex Role of Human Behavior in Urbanization and Resilience of Communities under Flood Risk

Abstract:

Urbanization plays a significant role in placing the lives and livelihoods of people at risk of flooding. Accessibility to commercial, recreational, and agricultural development has made riverine floodplains and coastal areas desirable places to live. Since urbanization changes the nature of the flood hazard, exposure, and risk, it needs to be thoroughly understood so that rapidly growing flood-prone communities can develop effective policies to manage and mitigate this risk. Current methods for accounting for the role of urbanization on flood risk are limited to static methods (e.g. prescribing different scenarios for population statistics and economic development in future) rather than utilizing high-resolution urban simulation models, revealing the dynamics associated with urbanization process. As such, traditional methods cannot incorporate the physical, environmental, social, and behavioral urban growth complexities.

To overcome these limitations our goals are: 1) To develop a spatially explicit model to simulate the growth of an urban area over time, considering geographical, physical, social, and economic factors associated with urbanization; and 2) To evaluate the role of land-use policies and socioeconomic incentives, such as acquisition, zoning, and taxation in mitigating flood consequences and moving toward resilient communities in flooding events. To fulfill the research objectives, we propose to couple an Agent-Based Model (ABM) and a hydraulic model. The ABM captures the behavior of economic, heterogeneous agents, such as households, developers, real estate agents, and government agencies to model the dynamic interactions within a city and at the city boundaries that occur as a part of urban growth. This urban growth model is coupled with a 2D unsteady hydraulic model to obtain floodplain extent and depth across the considered test-bed community at different flood return periods, which is then used for determining risk under different scenarios. Furthermore, we will demonstrate that this methodology could be used to assist city planners and stakeholders in examining tradeoffs between costs and benefits of future sustainable land development, considering uncertainties in flood hazards, the performance of the built environment, and future patterns of population and economic growth.