Evaluation of water quality in Zarqua river and King Talal Dam

Abstract

Construction of the King Talal Dam was started in 1972, with thepurpose of impounding the flood water of the Zarqa Valley. In March 1977water started being collected in the King Talal Dam. Its water is of utmostimportance to Jordan with a semi-arid Mediterranean climate, and an annualrainfall ranging between 250-550 mm, falling mainly in the periodNovember to April. This water is used in dry season for irrigation and inthe future for generating electricity.The Zarqa River was the main source of pollutants to the KingTalal Reservoir, particularly during floods. At such times, the stream bedwas flushed and all the deposited material were resuspended and carried tothe King Talal Reservoir. These pollutants have had a rapid but annuallyvariable effect on the King Talal Reservoir's water quality. Instead of aclean, oligotrophic water body, we have a highly productive, eutrophic lakethat since 1978 exhibits a striking chemical stratification which accompaniesthe normal theory with a stratified period of nine months extending fromMarch to December. At present, the reservoir supplies water toapproximately 120 km2 of agricultural land in Jordan.In this thesis, a physical study of the region - Zarqa River andKing Talal Dam in Jordan - is conducted. The physical, chemical, andbiological parameters are examined at several sites to determine the reasonsfor the deterioration of the water quality in the river and the reservoir.The effect of urbanization and human activities on both the riverand the dam are discussed. Analysis of past and present situations andpossible environmental impacts on the area is conducted, in addition to thedegree of pollution that the reservoir is exposed to and its effect on thesurrounding environment.The dam was found to be highly eutrophic. Zarqa River water isnot suitable for irrigating all kinds of crops. And pollution parameters inthe dam and the river are very high.