Using the Resistivity Method for Leakage Detection at Sant Llorenç de Montgai Embankment (Lleida, NE Spain)

The infiltration through the core of foundation of embankment dams is a main concern for maintenance and safety. The mechanism of infiltration induces internal erosion which can be progressive and can disturb the stability and the durability of the structures. Internal erosion occurs when water flows through a cavity, crack, and/or other continuous void within the embankment. Geophysical survey at Sant Llorenç de Montgai embankment has evinced the effectiveness of the ERT technique in assessing the state of the dam embankment. In particular, the method has revealed areas with high electrical resistivity values related with mortar injection. In the other side, we have registered areas with very low electrical resistivity values correlated with areas with possible abnormal seepage.