A software tool for rapid flood inundation mapping

Abstract

For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment-visit http://www.usgs.gov or call 1-888-ASK-USGS.For an overview of USGS information products, including maps, imagery, and publications, visit http://store.usgs.gov Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner.Suggested citation: Verdin, James; Verdin, Kristine; Mathis, Melissa; Magadzire, Tamuka; Kabuchanga, Eric; Woodbury, Mark; and Gadain, Hussein, 2016, A software tool for rapid flood inundation mapping: U.S. Geological Survey Open-File Report 2016-1038, 26 p., http://dx.doi.org/10.3133/ofr20161038. AbstractThe GIS Flood Tool (GFT) was developed by the U.S. Geological Survey with support from the U.S. Agency for International Development's Office of U.S. Foreign Disaster Assistance to provide a means for production of reconnaissance-level flood inundation mapping for datasparse and resource-limited areas of the world. The GFT has also attracted interest as a tool for rapid assessment flood inundation mapping for the Flood Inundation Mapping Program of the U.S. Geological Survey. The GFT can fill an important gap for communities that lack flood inundation mapping by providing a first-estimate of inundation zones, pending availability of resources to complete an engineering study. The tool can also help identify priority areas for application of scarce flood inundation mapping resources. The technical basis of the GFT is an application of the Manning equation for steady flow in an open channel, operating on specially processed digital elevation data. The GFT is implemented as a software extension in ArcGIS. Output maps from the GFT were validated at 11 sites with inundation maps produced previously by the Flood Inundation Mapping Program using standard one-dimensional hydraulic modeling techniques. In 80 percent of the cases, the GFT inundation patterns matched 75 percent or more of the one-dimensional hydraulic model inundation patterns. Lower rates of pattern agreement were seen at sites with low relief and subtle surface water divides. Although the GFT is simple to use, it should be applied with the oversight or review of a qualified hydraulic engineer who understands the simplifying assumptions of the approach.

Cooperative operation of the Grand Ethiopian Renaissance Dam reduces Nile riverine floods

“…Although GFT uses simplified approaches, its validation by Verdin et al (2016) showed agreement with one-dimensional hydraulic models at 11 sites in the United States, one site on the Okavango River in Namibia, and two sites on the Blue Nile River in Sudan.…”

“…The GIS Flood Tool (GFT;Verdin et al (2016)) was used to develop a reconnaissance-level flood inundation model for the Nile within Khartoum State, Sudan. GFT was developed by the U.S. Geological Survey supported by the U.S. Agency for International Development's Office of U.S. Foreign Desaster Assistance.…”

Extending Height Above Nearest Drainage to Model Multiple Fluvial Sources in Flood Inundation Mapping

“…Related to these efforts, the United States Geological Survey (USGS) has invested in relative elevation HAND-like methods via work in the GIS Flood Tool (GFT) that also uses SRCs with cross-sections for stage-discharge relationships (Verdin et al, 2016).…”

Extending Height Above Nearest Drainage to Model Multiple Fluvial Sources in Flood Inundation Mapping Applications for the U.S. National Water Model

“…Related to these efforts, the United States Geological Survey (USGS) has invested in relative elevation HAND‐like methods via work in the GIS Flood Tool (GFT) that also uses SRCs with cross‐sections for stage‐discharge relationships (Verdin et al., 2016). Additional investment by Petrochenkov (2020) was able to successfully scale this approach by transitioning the method to open‐source Python source code (PyGFT) and implementing novel interpolation methods to help address some of the catchment boundary discontinuities discussed more in this paper.…”