BOREHOLE WATER LEVEL STABILIZATION SYSTEM FOR CAST-IN-PLACE PILE

PROBLEM TO BE SOLVED: To provide a borehole water level stabilization system for a cast-in-place pile, capable of stabilizing a water level of a stabilizer inside a pile hole even on a site where a groundwater level is high or a site where a position to drill the pile hole and an installation position of a tank are separated.SOLUTION: In a borehole water level stabilization system 1 for the cast-in-place pile including supply means 4 for supplying the stabilizer to a drilling hole H, discharge means 5 for discharging slurry from the drilling hole H together with drilled sediment, water level detection means 6 for detecting the water level of the stabilizer supplied into the pile hole H, and control means 7 for controlling them, the supply means 4 includes a stabilizer tank 40 for storing the stabilizer, a feed pump 42 for sending out the stabilizer from the stabilizer tank into the pile hole, and a supply route 44 from the stabilizer tank 40 to the inside of the pile hole H. A check valve 44b is provided near a proximal end to be a feed pump side of the supply route 44, a motor valve 44a is provided near a distal end to be the side of the pile hole H, and the stabilizer is made storable inside the supply route 44 between both valves.