Grey water footprint for evaluating Zefta wastewater treatment plant: a case study.

The numbers of wastewater treatment plants (WWTP) in Egypt are increasing, yet the general level of pollution associated with wastewater discharge after treatment has not been evaluated. Grey water footprint (GWF) was used to assess the effluent discharges from Zefta WWTP. GWF, before and after treatment, was calculated and followed up to determine its impact on the receiving freshwater body.