Geophysical Applications for Levee Assessment

Levees are important engineering structures that are built along the rivers to protect human lives and shield the communities as well as agricultural lands from high water events. Animal burrows, subsurface cavities, and low density (high permeability) zones are weaknesses within the levee body that increase its risk of failure. To prevent such failures, continuous monitoring of the structural integrity and early detection of weaknesses in the levee should be conducted. The Ground Penetrating Radar (GPR) and the Capacitively Coupled Resistivity (CCR) methods were examined to detect the previous problems. Also, studying the capability and the effectiveness of these methods in levee monitoring, subsurface weakness detection, and studying the structure integrity of levees were the main tasks of this work. A set of laboratory experiments and a comprehensive field work in three levees were conducted to achieve the work goals. The GPR was effective to detect the cavities and the animal burrows as well as the low compaction areas. The CCR was less effective in detecting animal burrows and other small anomalies due to the nature of the method.