FACILITY FOR INTAKE OF GROUNDWATER FROM BEDROCK, AND METHOD FOR CONSTRUCTING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide intake facilities capable of surely and stably performing water intake from a freshwater lens, and an effective and proper construction method capable of preventing the freshwater lens from being deformed in the construction of the intake facilities.;SOLUTION: The facilities include: a vertical shaft 4 which is provided in such a manner as to reach the bottom of the freshwater lens 3; a water collecting hole 5 which is drilled around the vertical shaft from the bottom thereof; a water pouring hole 8 which is provided in a position below the water collecting hole 5 so as to pour feed water to the bottom of the freshwater lens; and a water pouring borehole 12 which is drilled in the freshwater lens from a ground surface so as to pour the feed water into the freshwater lens. In the construction, the water pouring borehole is precedently constructed; and vertical shaft, the water pouring hole and the water collecting hole are constructed while the feed water is poured into the freshwater lens. An underground wall functioning as an underground dam is provided at the peripheral edge of the freshwater lens in such a manner as to surround the freshwater lens.;COPYRIGHT: (C)2011,JPO&INPIT