Professor of Civil and Environmental Engineering, Urban Planning and Public Policy University of California, Irvine
Flooding disasters are becoming increasingly frequent, driven by expanding cities and a warmer climate capable of generating more intense and prolonged precipitation. Infrastructure designed decades ago to contain extreme flood events is now aging and undersized. A recent study of Los Angeles, California suggests that the population exposed to the 100-year flood is at least 10 times larger than suggested by Federal Emergency Management Agency (FEMA), and that risks are disproportionately higher for non-Hispanic Black and disadvantaged populations, burdening communities that may have greater challenges recovering and reinforcing socioeconomic inequities. Numerous state and federal initiatives aspire to deliver greater environmental justice with infrastructure investments, yet processes of achieving environmental justice through infrastructure planning and design are nascent and unproven. Herein we present a multi-dimensional framework of exposure assessment for assessing the equity of existing and proposed flood infrastructure, and for facilitating stakeholder engagement and collaborative design. The framework involves detailed, street-resolution simulation of flooding across entire metropolitan regions and the aggregation of data at scales of decision-making (households, communities, municipal government, regional government). Simulations and aggregated data (i.e., impacts) collectively enrich an inclusive process of community engagement seeking to understanding the distribution of costs and benefits of proposed actions and to identify the most promising infrastructure investments considering effectiveness, equity, and sustainability in the near and long term.
