Evaluation of flood metrics across the Mississippi-Atchafalaya River Basin and their relation to flood damages.
Keith E Schilling, Elliot S Anderson, Jerry Mount, Kelly Suttles, Philip W Gassman, Natalja Cerkasova, Michael J White, Jeffrey G Arnold
Author Information
Keith E Schilling: Iowa Geological Survey, University of Iowa, Iowa City, Iowa, United States of America. ORCID
Elliot S Anderson: IIHR-Hydroscience & Engineering, University of Iowa, Iowa City, Iowa, United States of America. ORCID
Jerry Mount: IIHR-Hydroscience & Engineering, University of Iowa, Iowa City, Iowa, United States of America. ORCID
Kelly Suttles: Environmental Defense Fund, Raleigh, North Carolina, United States of America. ORCID
Philip W Gassman: Center for Rural and Agricultural Development, Iowa State University, Ames, Iowa, United States of America.
Natalja Cerkasova: Texas A&M AgriLife Research, Blackland Research and Extension Center, Temple, Texas, United States of America. ORCID
Michael J White: Department of Agriculture, Grassland Soil and Water Research Laboratory, Agricultural Research Service, U.S. Temple, Texas, United States of America.
Jeffrey G Arnold: Department of Agriculture, Grassland Soil and Water Research Laboratory, Agricultural Research Service, U.S. Temple, Texas, United States of America.
Societal risks from flooding are evident at a range of spatial scales and climate change will exacerbate these risks in the future. Assessing flood risks across broad geographical regions is a challenge, and often done using streamflow time-series records or hydrologic models. In this study, we used a national-scale hydrological model to identify, assess, and map 16 different streamflow metrics that could be used to describe flood risks across 34,987 HUC12 subwatersheds within the Mississippi-Atchafalaya River Basin (MARB). A clear spatial difference was observed among two different classes of metrics. Watersheds in the eastern half of the MARB exhibited higher overall flows as characterized by the mean, median, and maximum daily values, whereas western MARB watersheds were associated with flood indicative of high extreme flows such as skewness, standardized streamflow index and top days. Total agricultural and building losses within HUC12 watersheds were related to flood metrics and those focused on higher overall flows were more correlated to expected annual losses (EAL) than extreme value metrics. Results from this study are useful for identifying continental scale patterns of flood risks within the MARB and should be considered a launching point from which to improve the connections between watershed scale risks and the potential use of natural infrastructure practices to reduce these risks.
References
Nat Commun. 2019 Jan 25;10(1):430
[PMID: 30683855]
