In order to evaluate the dam safety of Tanzikou reservoir, the arch dam and its gravity abutments on the left and right sides of the reservoir have been studied to ascertain the defects and the main reasons causing the defects. Results indicate that defects do exist due to irreasonable designs and poor construction quality of the arch dam. On the basis of the reasons causing the defects of the arch dam, treatment measures and design proposal have been put forward in this study. Results of the observation and inspection after the treatment of the dam have justified the feasibility of the treatment measures. Furthermore, a satisfactory operation of the dam has been obtained.
