Evaluation of irrigation water quality of dam Dahmouni in Cheliff watershed upstream of Boughzoul,Algeria

Despite their agronomic values,discharges of badly treated wastewater of the city of tiaret in dam dahmouni,could seriously affect the quality of its waters intended exclusively for the irrigation of large agricultural areas in the cheliff watershed upstream of boughzoul. the ratios adopted for assessing the quality of the urban effluents allowed to highlight their domestic origin and the partial biodegradability of their organic matter. according to the same criteria,we could deduce the non-biodegradability of the organic matter contained in the waters of dam dahmouni. moreover,the physico-chemical and bacteriological analyzes of waters have revealed some deviations from fao (1985) and who (1989) standards,which deserves to be mentioned. on physico-chemical level,the results showed a slight excess of cadmium and a slight to moderate degree of restriction,according to the fao (1985) classification for irrigation water in periods of study (2008 and 2009). bacteriologically,important values of faecal coliforms were identified in all samples despite the existence of wwtp upstream of dam dahmouni. to endow the wwtp of tiaret with a suitable disinfection system,followed by a regular monitoring can significantly improve the quality of these waters.