A method of using pressurized water, heated or unheated, with or without detergent, to prepare surfaces for coating. Low-pressure water cleaning uses pressures up to about 43 MPa (5,000 psi); high-pressure water cleaning ranges from 34 MPa (5,000 psi) to 170 MPa (25,000) psi; and ultrahigh-pressure water cleaning uses pressures above 170 MPa (25,000 psi). When pressures exceed 69 MPa (10,000 psi), a jet nozzle is used and the process is called water jetting.