A method for recovering oil from an oil bearing formation including the steps of: i) recovering an oil-water mixture from the oil-bearing formation; ii) separating at least a portion of the oil from the oil-water mixture to form a produced water; iii) adding a polymeric alkylene oxide surfactant having a Mw of less than 10000 Da to the produced water; iv) passing the produced water through a polymeric membrane to form a permeate stream and a retentate stream; and v) injecting the permeate stream into the oil bearing formation.