Assessment of Changes in Flood Frequency Due to the Effects of Climate Change: Implications for Engineering Design

Abstract

The authors explore the uncertainty implied in the estimation of changes in flood frequency due to climate change at the basins of the Cedar River and Skunk River in Iowa, United States. The study focuses on the influence of climate change on the 100-year flood, used broadly as a reference flow for civil engineering design. Downscaled rainfall projections between 1960-2099 were used as forcing into a hydrological model for producing discharge projections at locations intersecting vulnerable transportation infrastructure. The annual maxima of the discharge projections were used to conduct flood frequency analyses over the periods 1960-2009 and 1960-2099. The analysis of the period 1960-2009 is a good predictor of the observed flood values for return periods between 2 and 200 years in the studied basins. The findings show that projected flood values could increase significantly in both basins. Between 2009 and 2099, 100-year flood could increase between 47% and 52% in Cedar River, and between 25% and 34% in South Skunk River. The study supports a recommendation for assessing vulnerability of infrastructure to climate change, and implementation of better resiliency and hydraulic design practices. It is recommended that engineers update existing design standards to account for climate change by using the upper-limit confidence interval of the flood frequency analyses that are currently in place.

Climate Change Impact on Flood Frequency and Source Area in Northern Iran under CMIP5 Scenarios

“…Among various methods for flood-risk characterization, flood magnitude and frequency analyses are recognized as essential variables in flood-risk management studies [3]. Changes in frequency and intensity of flood events can lead to severe impacts on different aspects of human life including environmental, social, and economic conditions [17]. In this regard, flood frequency analysis is a statistical approach that provides a probability model using annual flood peaks during a given period [18].…”

Social Acceptability of Flood Management Strategies under Climate Change Using Contingent Valuation Method (CVM)

“…Floods are natural hazards with detrimental effects on the economy, social facets, and environment [1]. According to the Intergovernmental Panel on Climate Change (IPCC), climate change has had significant influence on magnitude and frequency of flood events in regions all over the world [2].…”

Climate‐Induced Changes in the Risk of Hydrological Failure of Major Dams in California

“…We adopt the 100-year flood (peak flow with a 1% annual chance of occurrence) concept not only because several studies have used this index to quantify flood hazard (e.g., Arnell & Gosling, 2016;Hirabayashi et al, 2013;Quintero et al, 2018;Wobus et al, 2017) but also because different agencies in the United States, historically and commonly, use the 100-year flood level to conduct flood risk assessment (e.g., Dankers et al, 2014;Federal Emergency Management Agency, 2014;Morss et al, 2005). We also compute changes in the return period corresponding to historically 100-year flood as another indicator of change in the flood hazard.…”