The invention relates to a construction method of a
coral island
reef underground
fresh water collecting facility, which comprises the following steps of: 1, performing a technical exploration on a
coral island
reef to be constructed; 2, constructing an annular waterproof
curtain wall; 3, constructing a permeability reducing layer by adopting a high-pressure fixed-depth grouting process, wherein the permeability reducing layer is connected with the bottom of the waterproof
curtain wall; and 4, building a rainwater collection and infiltration-assisting
pipe network
system. By the adoption of the construction method of the
coral island
reef underground
fresh water collecting facility, the waterproof
curtain wall which is annular and closed and has a depth capable of reaching a Pleistocene
karst aquifer is built on a stratum of a coral island reef
land area, the rainwater collection and infiltration-assisting
pipe network
system for enhancing rainwater infiltration and the permeability reducing layer for reducing a
permeability coefficient of a Holocene and Pleistocene
unconformity surface stratum are constructed under the land surface, so that a huge underground
water storage container positioned in the whole island reef stratum is constructed, the container is continuously supplemented by rainfall so as to solve the problems of small amount, extremely fragile and unstable available
fresh water of the coral island reef fresh water lens body in a
natural state.