Seepage Mapping

Dam Seepage Mapping

Understanding and mapping seepage on earthen structures, including dams, embankments, levees, and tailings storage facilities, is essential for the integrity and long-term care of these structures.  According to FEMA, the second largest cause of earthen dam failure worldwide results from internal erosion caused by seepage.  Damage from seepage and internal erosion can lead to earthen structure failure, destruction of property, environmental damage, and even loss of life.  Thus, having the capability to create an image of the internal workings of these structures and understand their integrity remains a core objective to protecting these critical assets.  Facing this challenge head-on, HGI has developed a toolbox of geophysical technologies to investigate and assess the reliability of earthen structures, including dams, embankments, levees, and tailings storage facilities.  Our methods can locate and identify areas of concern related to abnormal seepage or piping, in order to mitigate costly damage and failure.

 

Mapping and understanding seepage is a critically important factor for protecting a dam’s integrity.

Fence diagram of an electrical resistivity survey conducted on an earthen dam to determine the seepage pathways through the dam structure. The multiple survey lines clearly indicate the seepage as the more conductive region and allow the preferential pathways to be mapped and understood for follow-on remediation efforts.
 

HGI has adapted our geophysical technologies to offer a more holistic view by using methods such as electrical resistivity, seismic, nuclear magnetic resonance, and streaming potential (SP) surveys, to create an internal picture of these complex structures.  These geophysical characterization methods offer a versatile and adaptable toolbox and are an ideal, cost-effective solution for assessing the hydrodynamic character of earthen structures.