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Funded by: the U.S. Department of Homeland Security
Managed under the Southeast Region Research Initiative (SERRI) by the U.S. Department of Energy, Oakridge National Laboratory

This project was conducted by faculty in the Department of Geography and Geology at the University of Southern Mississippi (USM) in Hattiesburg, MS through partnerships with the U.S. Army Engineer Research and Development Center, Geotechnical and Structures Laboratory, Vicksburg, MS, and the Biedenharn Group also of Vicksburg.

Introduction

With the catastrophic destruction from Hurricane Katrina in New Orleans, LA, in 2005 and the recent flooding from failed levees in Iowa, the risks and consequences associated with urban development along levees must be better understood. Damage estimates from Katrina alone is as high as 125 to 200 billion dollars, and almost half of these damages are attributable to flooding (Ritter 2005; Van der Vink et al. 2005). One very important aspect often overlooked when levees are constructed along rivers is that levees are constructed without complete knowledge of the subsurface geological environment. Current levee assessment relies on visual inspection and widely-spaced soil borings are used to classify levee materials and to determine engineering properties. Unfortunately, weaknesses along levees are not always easily identified from visual inspection or widely-spaced borings as subsurface conditions can rapidly vary due to geology and land use changes.

The obvious solution to understanding the threat of a levee failure to public safety is better levee assessment methods using rapidly deployed geophysical methods, in addition to visual inspection methods and borings spaced at fixed intervals. The application of airborne geophysical methods for determining levee classification, condition, and ranking methodologies has the potential to greatly influence maintenance practices within the federal government, as well as many local and state-owned levee systems. It is of utmost importance to rapidly screen levees to locate areas of weakness in the subsurface before any adverse conditions arise and threaten levee stability. The key to the solution is a technically advanced levee assessment procedure and associated tools that can be easily and rapidly deployed in times of immediate need. The assessment procedure must also be user-friendly and applicable to levees nationwide without restrictions to geographic location, levee geometry, or levee materials.

The U.S. Army Engineer Research and Development Center (ERDC) Vicksburg is actively developing a levee assessment tool, Levee Condition Assessment Technology (LevCAT), to model the subsurface environment and target zones of weakness within the levee structure and also within the underlying soil matrix. Currently, LevCAT is the only such tool to rapidly model areas sensitive to levee stability. However, further calibration and validation of the tool is needed along with development of a platform for global access. A critical part of levee assessment involves the management and organization of data required for the analysis, especially as it relates to the understanding of the study area geology, soils data, and associated geophysical signatures. To meet these requirements, the refinement of LevCAT must include an interactive web-based platform and detailed conditions and specifications of levees through geophysical techniques. Furthermore, it must incorporate lessons from other classification methods and include evaluation of additional data sets of levee systems. The project addresses levee condition factors essential in the assessment of levee stability and, hence, public safety. In addition to the geologic environment, specifically the fluvial and flood regime, other factors are described in terms of levee foundation materials and levee construction methods. The focus of this research is to refine LevCAT and integrate the assessment and classification tool with an interactive visual application for global access. The proposed research will integrate a visual interface with existing assessment and classification procedures. The proposal addresses the Department of Homeland Security (DHS) relevance A: Infrastructure protection from natural or man-made disasters.

Choose "Project Details" from the above menu to learn more about this project. The prototype web mapping application can be lanched from the site by chooseing "Mapping Application" above.