Water Quality of Dohuk Dam Stream Outflow

Abstract

The Dohuk dam is located on the north of Dohuk city, it is consider as one of the main sources for water supplying to many places in the city for drink and domestic uses, dam water flowing through the narrow stream within the Dohuk valley finally reach to the Mosul dam. The study covered three locations from the Dohuk dam outflow stream, first from the bottom tunnel of the dam, second in Bourse bridge and third in Church bridge, the samples were taken from October 2010 until February 2011. The research aimed to water quality monitoring by determination some of physical, chemical and biological properties with respect to its potability for human uses.The electrical conductivity (EC) and total dissolved solids (TDS) values of water reach to 1116 s/cm and 899 mg/l, pH value was 9.1 in Bourse bridge location. Water of the Dohuk dam outflow stream was on the alkaline side. Total hardness recorded 603 mg/l CaCO3 in Church bridge location. The water of Dohuk dam outflow stream was classified as hard water as its hardness was higher than 300 mg/l (WHO, 2006). The Dissolved oxygen (DO) values were decreasing through the Dohuk dam outflow stream to reach 6.0 mg/l in Church bridge location. The values of Biochemical Oxygen Demand (BOD) increasing through the dam outflow stream to reach 4.1mg/l in Church bridge location, the number of bacterial colonies also increasing in the stream flow which was reached to 432 cells/ml in Church bridge location.