An Assessment of Biological Pollution in Certain Sector of Lower AL-Zab and River Tigris Waters Using Bacterial Indicators and Related Factors in Iraq

Abstract

This study was conducted during 2004 utilizing selected sectors of River Tigris and the Lower Al-Zab River among Kirkuk and Salahaldeen Governerates of Iraq. Water samples from eight stations were analyzed for total coliforms, fecal coliforms, total viable counts of bacteria, Oxygen biological demand (BOD), water turbidity, electrical conductivity and temperature. The present study revealed a wide variation in the water quality due to different pollution pressures affected the different sites of River Tigris and Al-Zab River waters. These water sources are used for drinking and other human activities. The Lower Al-Zab River was less affected by the mentioned factors compared to River Tigris. The analysis of variance showed a significant difference between BOD values recorded at different months and the P value was less than 0.5. The overall mean of BOD was 2.4 mg/l which is suitable for human consumption after drinking water purification process with reference to European characterizations 74/464/EEC of waters used as sources for drinking waters.