Abstract:The construction of underground reservoir has become a good measurement and basic method to solve the water supply in the world,and the key of this engineering is the construction of underground inter-seepage dam. The project of the underground reservoir in littoral zone of the Yantai City is taken as a case study. Based on the analysis of ground condition of hydrogeology and engineering geology,the design parameters of the underground reservoir inter-seepage dam in pebble bed are studied. Two new structure types of the underground reservoir inter-seepage dam in pebble bed are proposed. Their structure characteristics are also analyzed. The construction parameters and quality control of the inter-seepage dam in pebble bed are discussed. Finally,the impervious effects are tested and analyzed.