PURPOSE: To lower a ground water level easily when the ground water level in the periphery of a basement rises.

CONSTITUTION: All external surfaces lower than the ground surface 2 of a box-shaped concrete structure 1 constituting a basement 1a are covered with a permeable layer 3 composed of gravel, crushed stone, pebble, etc., in drainage structure. A drain pipe 4 reacting the lower section of the concrete structure 1 from the upper section of the ground surface 2 is buried into the permeable layer 3. A large number of through-holes are formed to the side face of the drain pipe 4. Undergroundwater in the drain pipe 4 is sucked by a pump P, etc., and drained, thus lowering the ground water level of the permeable layer 3 having excellent drainage.