Abstract
Groundwater is a limited resource, its abundance directly affect the development of the island with mainly the aspects of agriculture and household.
In order to secure a stable supply of groundwater resources, some underground dams have been already constructed. However, the ground structure of the island that can be applied is required for that. It is impossible to construct the conventional underground dam in the isolated island that has the underground structure of the fresh water lens. To apply the dam-construction technology fit to the closed environment is a promising way to enhance the utility of water resource in such island.
