Abstract

Tropical Storm Debby brought severe flooding to portions of southwestern Florida during the summer of 2012. Remotely-sensed images were collected to document the flooding and test the results of Hydrologic and Hydraulic (H & H) storm water models constructed by the Southwest Florida Water Management District (SWFWMD). One image, a satellite, multi-band SPOT image was provided to the SWFWMD by the Federal Emergency Management Agency (FEMA). This image was collected within 48 h of the storm event. The SWFWMD also contracted for a very high resolution (60 cm Ground Sample Distance (GSD)) fCIR image to be captured for selected watersheds in Citrus, Hernando and Pasco counties, the areas most impacted by the flooding. Modeled floodplain results were compared to remotely-sensed images that were georeferenced and analyzed using remote sensing techniques. The higher resolution fCIR images more clearly identified flooding for better comparison with modeled results. Although the fCIR images, which were collected three to four days after the storm event, under predicted the overall extent of the modeled floodplain, as the images could not confirm the presence of flooding in areas obscured by dense vegetation, they did consistently confirm both the location and shape of flooding simulated by the model. By using image analysis methods on the Near-Infrared (NIR) band of the fCIR image in conjunction with the Digital Elevation Model (DEM), however, it was possible to identify the extent of flooding in those obscured areas. Field surveys of high water elevations indicated that many locations had receded within hours of the storm event, limiting the ability of the fCIR image from capturing peak flood level in all areas. Overall, these remotely-sensed images provided a good validation of predicted flood levels for a design storm of the magnitude of Tropical Storm Debby.

Highlights

  • Floods are a natural phenomenon that causes an average of about $6 billion in damages annually (Sarmiento and Miller [1])

  • Field surveys of high water elevations indicated that many locations had receded within hours of the storm event, limiting the ability of the false-color infrared (fCIR) image from capturing peak flood level in all areas

  • Modeled floodplain results show that 21 percent of the total Peck Sink Watershed was inundated during Tropical Storm Debby

Read more

Summary

Introduction

Floods are a natural phenomenon that causes an average of about $6 billion in damages annually (Sarmiento and Miller [1]). In some cases, flooding is expected, while in many others the public is unaware of the risk and unprepared for the consequences. Local, state and federal agencies have worked to develop tools to accurately identify flood risk and to quickly respond to flooding when it happens. Flood protection is one of the four major missions of the Southwest Florida Water. Toward this mission, the SWFWMD cooperates with federal and state entities, and local governments to develop Federal Emergency Management Agency (FEMA). During the development of the DFIRMs, the SWFWMD investigates: (1) the results of storm water models; (2) a database of historical photographs and high

Methods
Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.