Methods, systems and apparatus for cleaning turbines, such as power generation turbines, are disclosed. Supplemental piping is connected to existing compressor air extraction and turbine nozzle cooling air piping, to supply water and/or cleaning agents into areas of a turbine not ordinarily accessible by injection of water and/or cleaning agents into the bellmouth of the turbine alone. Pressure and flow sensors, pumps, valving, and a control system to regulate the operation of the pumps and valving are provided to control the introduction of water and/or cleaning agents into the turbine.