Sponsored by the Southwest Region University Transportation Center, researchers at Texas A&M University's Department of Civil Engineering have developed a technology that uses induced polarization and electrical resistivity to "see" underground and determine if a bridge has maintained its designed margin of safety with regard to foundation depth. Stefan Hurlebaus, Jean-Louis Briaud, and Stacey Tucker tested a unique method of examining the bridge-weakening effects of scour on unknown bridge foundations. Scour is the void left behind when the sediment (soil, sand, and rock) washes away from the bottom of a river and from around the bridge piers and abutments that support the bridge. Heavy scour around bridge foundations can be a sign of instability—depending on how deep the foundation goes. This is why finding and knowing that depth is so important to bridge engineers.