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Abstract Introduction: There are many colloidal and suspended solids in surface water for which coagulants should be used in process of water treatment. Plyaluminum chloride (PACl) is one of the newest coagulants . In this research, PACl has been used to coagulate water samples token from Arvandrood and Bahmanshir rivers as the main water suppliers of Abadan City. Materials and Methods: A necessary number of water samples were taken during normal conditions from water sources of Abadan. The turbidity of a few samples was intentionally increased by addiny clayey soil because the turbidity of Abadan Rivers increases considerably in rainy seasons. The optimum coagulant doses and coagulation condition were then determined by standard Jar tests. Besides, residual Al and COD concentrations in finished water samples have been determined along with routine analyses of water. Results: The results show that turbidity removal rate from sample waters in Jar tests were 90 to 98 % and Al residual concentrations were about 0.41 mg/L. For samples with high turbidity, the removal rates were 98 to 99 %, but the Al residuals were about 0.06 mg/L. Conclution: Since the concentration of all pollutants decreased to less than their MCL values after the treatment of water with PACl , it can be concluded that using this new chemical dose not produce any adverse health effect. Considering the various advantages vis a vis conventional coagulation, PACl can be recommended to be used in trwating water in the Abadan plant. ***