By analysing the authors realize that once the leaking channel along the discharge culvert pipe periphery connect with the termitarium and the termitic passage at its termination, a rapid dam collapse difficult to rescue will easily occur.

Detecting the dam-detouring leakage passage in the left dam abutment of Douhe Reservoir with the method of heat source;

Using line-heat-resource method to study concentration leakage passage of dike;

Leakage is the main form which influences dyke safety severely,so to determine the position of the leakage passage is the precondition and base of dyke repair.