The surface water contain some dissolved contaminants such as iron and manganese. It is unsuitable for drinking water without appropriate treatment. Under standard and steady-state conditions, the bioreactor was very effective when 2% of the nano polymer composite granules (w/v)borne bioagent bacteria as a substrate for the biofilm formation. The mixture was aerated for 24 hs. The treated water have been uptake for determination the concentration of cations and microbiological analysis. Each 1L of surface water sample with continuous aeration and left for 24h and as a result many physical, chemical and bacteriological changes occurred .For the surface water temperature decreased by 2.2°C and 2.0°C related to raw water and chlorinated water , pH increased by 0.2 and 0.4 ppm related to raw water and chlorinated water . TDS decrease from (276 to 220 ppm) while in chemical treatment increase to (285 ppm) also conductivity decrease from(434 to 425) US/CM but increase to(442 US/CM) in the chlorinated treatment , while turbidity increase from (9.8 to 10.3) NTU. The elimination of the heavy metals was remarkable in this study as in rate of Fe that decrease from (0.39 to 0.21)ppm and for Mn it remains constant .Total alkalinity decrease from(142 to 130) ppm while in chemical treatment was 120 ppm. calcium hardness decrease from (78 to 54) ppm and as a result the calcium decrease from (31.2 to 21.6)ppm and in chemical one it has the same value of the raw water sample .Magnesium hardness increase from (100 to 108 )ppm &for the magnesium ion increase from (10.56 to 16.8) ppm. The chlorides decrease to 20 ppm in the bio treated water sample but it was normal to increase to 31 ppm in the chemical treated sample. Sulfates content decrease from (15.5 to 10.7)ppm but in chemical treatment it increase to 17 ppm. Phosphate content increase from(<0.01 to o.o2) ppm while the nitrate content decrease from(0.86 to 0.5) ppm it also decrease in the chemical treatment to 0.48 ppm and ammonia content decrease from (0.06 to0.01) ppm and in chemical treatment reach to <0.01 ppm a. Drinking water sources are contaminated with coliforms and pathogenic bacteria. The bacteriological results shows that all the bio treated sample had no fecal Coliform growth (<1) C/100ml but give positive results with the total Coliform with confluent colonies whereas in the chemical treatment both the total &fecal Coliform tests were negative.