This study considers the potential advantages of applying intermittent ultrasound to the ultrafiltration (UF) process to control long term membrane fouling in the context of water treatment. By means of parallel, benchscale tests using traditional coagulation pre-treatment prior to UF, and intermittent ultrasound during the operation (3 min/10 min every 3days), the development offouling material, andits nature (e.g. hydrophilic and hydrophobic), within the cake layer and membrane pores, have been evaluated in detail.