PURPOSE: To recover the permeable capacity of a pavement having water permeability by removing refuse, sand, etc., clogging the air gaps of the pavement having water permeability by mainly utilizing air pressure.

CONSTITUTION: A compressor 5 driven by arbitrary driving force is disposed to a car 1, and a spray nozzle 3 is connected on the discharge side of the compressor 5 toward the surface of a pavement. A suction port 4 opened to the surface of the pavement is connected on the suction side of the compressor 5. A makeup water tank 9 is bonded with a pipe 6 coupling the discharge side of the compressor 5 and the spray nozzle 3. Accordingly, only one compressor may be used though the two pumps of an injection pump and a vacuum pump have been required, thus simplifying structure.