Abstract:

      The investigation of karst reservoir area and dam foundation seepage often requires a great deal of manpower and considerable financial resources as well as techniques. Three examples for such investigation have been demonstrated in this paper. The results of tracing tests show that seepage is mainly controlled by the degree of karst development in reservoir adjacent areas, the intense fluctuation of reservoir water level is the main factor triggering the seepage. The seepage will weaken with the placidity of reservoir water level and filling of silt in the cavities. The results of tracing tests for sandy gravel dam foundation seepage indicate that the main seepage passages exist. Tracer test results can provide the basis for reservoir reinforce and seepage prevention. The large-scale tracing test is a complex investigation work, in which the key is to pay attention to entire tracing process and quality control.

Key words: reservoir seepage, groundwater, tracer, comprehensive analysis