Coupling effect of ozone/ultrasound with coagulation for improving NOM and turbidity removal from surface water

•Addition of the ultrasound/ozone (US/O3) to the coagulation process improved the NOM and turbidity removal.•The US/O3-coagulation could efficiently transform the high molar mass NOM into smaller and more biodegradable compounds.•The US/O3-coagulation process did not increase the bromate concentration, and its level was below the WHO acceptable limit.•No diagnosis of total coliform or Escherichia coli was observed in the samples treated by US/O3-coagulation.