Flood Risk Assessment and Quantification at the Community and Property Level in the State of Iowa

Abstract

Flood risk assessment contributes to identifying at-risk communities and supports mitigation decisions to maximize benefits from the investments. Large-scale risk assessments generate invaluable inputs for prioritizing regions for the distribution of limited resources. High-resolution flood maps and accurate parcel information are critical for flood risk analysis to generate reliable outcomes for planning, preparedness, and decision-making applications. Large-scale damage assessment studies in the United States often utilize the National Structure Inventory (NSI) or HAZUS default dataset, which results in inaccurate risk estimates due to the low geospatial accuracy of these datasets. On the other hand, some studies utilize higher resolution datasets, however they are limited to focus on small scales, for example, a city or a Hydrological United Code (HUC)-12 watershed. In this study, we collected extensive detailed flood maps and parcel datasets for many communities in Iowa to carry out a large-scale flood risk assessment. High-resolution flood maps and the most recent parcel information are collected to ensure the accuracy of risk products. The results indicate that the Eastern Iowa communities are prone to a higher risk of direct flood losses. Our model estimates nearly $10 million in average annualized losses, particularly in large communities in the study region. The study highlights that existing risk products based on FEMA's flood risk output underestimate the flood loss, specifically in highly populated urban communities such as Bettendorf, Cedar Falls, Davenport, Dubuque, and Waterloo. Additionally, we propose a flood risk score methodology for two spatial scales (e.g., HUC-12 watershed, property) to prioritize regions and properties for mitigation purposes. Lastly, the watershed-scale study results are shared through a web-based platform to inform the decision-makers and the public.

Predição de Resiliência Econômica a partir de Métodos Supervisionados baseados em Grafos Dinâmicos

“…O modelo de identificac ¸ão e mensurac ¸ão proposto por órgãos econômicos possuem uma relevância significativa [Hallegatte 2014], pois costumam considerar indicadores econômicos comuns a todos os países do globo e embasam diversos trabalhos recentes [Salignac et al 2022, Yildirim et al 2022. A identificac ¸ão da falha na sobrevivência do sistema econômico pode ser observada pela perda do potencial de produtividade (capital) da nac ¸ão (medida usualmente pelo Produto Interno Bruto, PIB).…”

Flood Susceptibility Mapping using Fuzzy Analytical Hierarchy Process for Cedar Rapids, Iowa

“…An integrated approach embraces risk management measures, their feasibility, and effectiveness in a multidisciplinary context, including social, economic, and environmental aspects (Hall et al, 2003). In the literature, community engagement (Rogers et al, 2020), crop loss (Yildirim and Demir, 2022b), intelligent systems and demographics (Eryilmaz Turkkan and Hirca, 2021) are introduced as potential improvements that the interdisciplinary flood risk management framework can provide. Furthermore, the outcomes of such approaches can provide new insights into existing risks in communities as well as informative risk maps for planning and preparedness.…”

Urban Flood Impact Assessment and Hazard Vulnerability Analysis: Iowa Case Study

“…The potential flood-related damage, including physical, economic, and social, can be estimated using HAZUS model software developed by FEMA, which focuses on estimating the direct impacts of flood damage, including structure and content (Cummings et al, 2012;Yildirim & Demir, 2021b). Indirect losses such as business losses may be worse than the direct impacts.…”