Thesis (doctoral)--Universität Heidelberg, 1926. / Includes bibliographical references (p. vii-x).

Thesis (doctoral)--Universität zu Köln, 1926. / Includes bibliographical references (p. vii-x).

Thousands of miles of levees exist in the United States and around the world and failure of these levees as a result of breaching has the potential to cause severe flooding damage. A technology, the PLUG, has been developed to temporarily reduce the flow through a levee breach as an alternative to traditional methods. This study is focused on developing initial guidance on the parameters for sizing a PLUG using a 1:100 (model:prototype) Froude scaled model. It was found that for the PLUG to effectively reduce flow through the breach, the required ratio of the PLUG length to the breach width is greater than two (L/W > 2), and that effectiveness increases as the ratio between the PLUG diameter and water depth (D/d) increases. Effectiveness also increases when the percent fill (P) is between 65 – 75 percent. Trends in the threshold between catastrophic failure and success were also noted.

The most common mode of levee failure, breach due to overtopping, is generally considered as a function of a complex set of contributing factors. The goal of this research is to enhance the state of the art and practice for performing levee overtopping risk assessment. For this purpose, a dataset of levee overtopping event records within the portfolio of levee systems maintained by the U.S. Army Corps of Engineers (USACE) is presented. The dataset is utilized with logistic regression analysis to develop a probabilistic model to calculate system response probabilities and assess risk related to levee overtopping. The presented dataset can be used for identifying key factors controlling overtopping behavior, validation of model results, and providing new insight into the phenomenon of levee overtopping. The proposed model offers a practical yet robust tool for levee risk analysis and can be readily employed by engineers and other stakeholders.

Levee breaching is the most frequent and dangerous form of levee failure. A levee breach occurs when floodwater breaks through part of the levee creating an opening for water to flood the protected area. According to National Committee on Levee Safety (NCLS), a reasonable upper limit for damage resulting from levee breaching is around $10 billion per year during 1998 and 2007. This number excludes hurricanes Katrina and Rita in 2005 which resulted in economic damages estimated to be more than $200 billion dollar and a loss of more than 1800 lives. In response to these catastrophic failures, the U.S. Army Corps of Engineers (USACE) started to develop the National Levee Database (NLD) on May 2006. The NLD has a critical role in evaluating the safety of the national levee system. It contains information regarding the attributes of the national levee system. The Levee Analyst Data Model was developed by Dr Norm Jones, Jeff Handy and Thomas Griffiths to supplement the NLD. Levee Analyst is a data model and suite of tools for managing levee information in ArcGIS and exporting the information to Google Earth for enhanced visualization. The current Levee Analyst has a concise and expandable structure for managing, archiving and analyzing large amounts of levee seepage and slope stability data. (Thomas 2009). The new set of tools developed in this research extends the ability of the Levee Analyst Data Model to analyze and mange levee breach simulations and store them in the NLD geodatabase. The capabilities and compatibilities with the NLD of the new geoprocessing tools are demonstrated in the case study. The feasibility of using GSSHA model to simulate flooding is also demonstrated in this research.

Coastal regions are continually plagued by high water levels induced by river flooding or hurricane induced storm surges. As with any protective structure, it is essential to understand potential problematic regions which could result in a devastating loss for the regions nations value most. Coastal protective systems are primarily comprised of floodwalls and levees, each of which has practiced methodologies utilized for estimating their performance under design conditions. Methodologies concerning spatial variability are limited however, and transitions where earthen levees merge with floodwalls are considered vulnerable areas to erosion and possible breaching. Physical modeling of a specified levee transition is undergone in a three-dimensional wave basin to evaluate this hypothesis, and the detailed results of this assessment are presented within this thesis. From the physical model testing, analysis of the data reveals that the overtopping rates of the levee transition tend to be larger than traditional overtopping techniques have predicted. The runup values and floodwall wave heights tend to show potential problematic areas and mimic the variation of overtopping along the levee transition. Under the design conditions tested, extreme overtopping conditions and associated water level values propose that in order for the structure to sustain the hydraulic conditions, it must be well protected. It is shown that the variation of the still water level plays the largest role in the magnitude of the measured values, and increasing the peak wave period and wave heights also yields greater overtopping and water levels at the structure. Overall these extreme overtopping rates and water levels experienced at the structure irrefutably expose a greater risk of erosion and breaching of the protective structure than initially predicted. This study highlights the need to understand specific spatial variability along coastal protective systems, and provides a better understanding of the mechanisms affecting overtopping for the specific structure tested.

The main focus of this research is to detect vulnerabilities on the Mississippi river levees using remotely sensed Synthetic Aperture Radar (SAR) imagery. Unstable slope conditions can lead to slump slides, which weaken the levees and increase the likelihood of failure during floods. On-site inspection of levees is expensive and time-consuming, so there is a need to develop efficient automated techniques based on remote sensing technologies to identify levees that are more vulnerable to failure under flood loading. Synthetic Aperture Radar technology, due to its high spatial resolution and potential soil penetration capability, is a good choice to identify problem areas along the levee so that they can be treated to avoid possible catastrophic failure. This research analyzes the ability of detecting the slump slides on the levee with different frequency bands of SAR data. The two SAR datasets used in this study are: (1) the L-band airborne radar data from NASA JPL’s Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR), and (2) the X-band satellite-based radar data from DLR’s TerraSAR-X (TSX). The main contribution of this research is the development of a machine learning framework to 1) provide improved knowledge of the status of the levees, 2) detect anomalies on the levee sections, and 3) provide early warning of impending levee failures. Polarimetric and textural features have been computed and utilized in the classification tasks to achieve efficient levee characterization. Various approaches of image analysis methods for characterizing levee segments within the study area have been implemented and tested. The RX anomaly detector, a trainingree unsupervised classification algorithm, detected the active slump slides on the levee at the time of image acquisition and also flagged some areas as “anomalous”, where new slides appeared at a later date. This technique is very fast and does not depend on ground truth information, so these results guide levee managers to investigate the areas shown as anomalies in the classification map. The support vector machine (SVM) supervised learning algorithm with grey level co-occurrence matrix (GLCM) features provided excellent results in identifying slump slides on the levee.

The objective of this thesis was to develop guidance for an anchored geotextile Rapidly Deployable Armoring System for the landward side of earthen levees to mitigate the effects of storm surge and overtopping waves. A case study of the Backwater Levee protection placed during the 2011 Mississippi River flood by the US Army Corps of Engineers was performed to prove construction feasibility. Full scale anchor testing was performed for 0.3 and 0.6 m rod shaped anchors to determine their load deflection behavior. Anchor test data and shear stress profiles based on flume testing presented in literature were used in conjunction with surface to surface contact interactions to develop a single-layer elastic membrane finite element model (SLEMM) of an RDAS to provide design guidance. The SLEMM appears to perform the finite element formulations correctly, but does not produce physically meaningful results. Further improvements to the model are needed for useable design.

Understanding and improving the state of the nation's levees has become a national priority following the devastating events surrounding Hurricanes Katrina and Rita. Federal legislation passed in 2007 created a new national Committee on Levee Safety and spurred the development of the National Levee Database, a central repository of information relating to the location and state of levees across the United States (Water Resources Development Act, 2007). One of the major goals in developing such a database is to improve the safety of America's levees. The National Levee Database, however, does not include features for storing seepage and slope stability data related to numerical analyses of levees. These data are critical in analyzing current levee conditions and predicting future failure scenarios, thus providing a path for further improving the safety of levees. The Levee Analyst is a new GIS data model and set of geoprocessing tools that make it possible to store and manipulate model data associated with seepage and slope stability analyses. The data model provides a concise structure for storing large amounts of levee seepage and slope stability data and also provides a structure that is expandable and compatible with the National Levee Database. The Levee Analyst combines the capabilities of various software systems in providing a data model and suite of tools that assists in further understanding and analyzing the state of America's levees.

The devastating levee failures associated with hurricanes Katrina and Rita, and the more recent Midwest flooding, placed a spotlight on the importance of levees and our dependence on them to protect life and property. In response to levee failures associated with the hurricanes, Congress passed the Water Resources Development Act of 2007 which established a National Committee on Levee Safety. The committee was charged with developing recommendations for a National Levee Safety Program. The Secretary of the Army was charged with the establishment and maintenance of a National Levee Database. The National Levee Database is a critical tool in assessing and improving the safety of the nation's levees. However, the NLD data model, established in 2007, lacked a structure to store seepage and slope stability analyses – vital information for assessing the safety of a levee. In response, the Levee Analyst was developed in 2008 by Dr. Norm Jones and Jeffrey Handy. The Levee Analysis Data Model was designed to provide a central location, compatible with the National Levee Database, for storing large amounts of levee seepage and slope stability analytical data. The original Levee Analyst geoprocessing tools were created to assist users in populating, managing, and analyzing Levee Analyst geodatabase data. In an effort to enhance the Levee Analyst and provide greater accessibility to levee data, this research expanded the Levee Analyst to include modifications to the data model and additional geoprocessing tools that archive GeoStudio SEEP/W and SLOPE/W simulations as well as export the entire Levee Analyst database to Google Earth. Case studies were performed to demonstrate the new geoprocessing tools' capabilities and the compatibility between the National Levee Database and the Levee Analyst database. A number of levee breaches were simulated to prototype the enhancement of the Levee Analyst to include additional feature classes, tables, and geoprocessing tools. This enhancement would allow Levee Analyst to manage, edit, and export two-dimensional levee breach scenarios.