The agricultural irrigation canal project in Wuzhong City, Ningxia, utilizes a composite geomembrane with two geotextiles and one membrane for seepage prevention. The top layer is compacted with 50mm concrete. After completion of the construction, a seepage detection of the seepage prevention surface was conducted using the double-electrode detection method. No seepage points were found during the detection, indicating the seepage prevention system is in good condition.