Research on application of salt tracer method and resistance method for determining water flow through the dyke body of Tac Giang sluice, Ha Nam province

Nguyen Nhu Trung1,*, Nguyen Quoc Dung2, Dinh Xuan Trong2, Bui Van Nam1, Nguyen Canh Thai3, Nguyen Van Diep1, Nguyen Thi Thu Huong1
Received: 3 September 2020; Accepted: 26 November 2020
 

Abstract
Seepage or leakage through the dyke and dam bodies of reservoirs are one of the main reasons of dyke and dam break causing significant damage to people, houses and crops around the reservoirs. Determining the location and velocity of seepage flow is an important and regular task in dam safety management and monitoring. In this paper we present an effective combination of methods of salt tracer, resistance measurement in wells and electrical resistivity tomography to determine the direction and velocity of water flows through the dyke body. Repeated measurements of the resistivity values in wells and the electrical resistivity tomography were carried out in three monitoring wells on the dyke and a line outside the dyke area in Tac Giang sluice, Ha Nam. The results of data analysis have identified the direction of underground flows through the dyke body on Tac Giang sluice in the NW-SE direction. The velocity of the water flow through the dyke body was determined to be 0.00078 m/s and the velocity of water flow through the dissipation tank was 0.00318 m/s
Keywords: Electrical resistivity tomography, groundwater flow, salt tracer, dyke, dam.