SUMMARY
This work focuses on Environmental impacts associated with concentrated brine rejection arising from seawater desalination plants in Algeria. We present a case study on the environmental impacts of BouIsmail/MSF seawater desalination plant. These impacts are mostly due to the highly saline brine that is discharged into the sea, which may be increased by temperature, contain residual chemicals from the pretreatment process, heavy metals from corrosion or intermittently used cleaning agents.We performed the measurement of seawater quality the concentration of heavy metals in an accumulator bio-algae and sediment in the turn of the rejection of the station. And the study of the phytoplankton density at different discharge distance. Global results show no effect while there is a local impact due to the relatively small size of the resort of plant.