ISSN 2320-5407 International Journal of Advanced Research (2016), Volume 4, Issue 1, 1536- 1542 1536 Journal homepage: http://www.journalijar.com INTERNATIONAL JOURNAL OF ADVANCED RESEARCH RESEARCH ARTICLE Correlation among Physico-Chemical and Microbial Parameters of Water Quality Characteristics of upstream, Degala Basin and downstream water body, Erbil- Kurdistan Region of Iraq Bakhtyar A. Othman Department of Biology, Faculty of Science and Health, Koya University Manuscript Info Abstract Manuscript History: Received: 08 November 2015 Final Accepted: 28 December 2015 Published Online: January 2016 Key words: Degala Basin, variation in physical and chemical parameter among both sites and microbial characteristics. *Corresponding Author Bakhtyar A. Othman The present study was carried out on the correlation of physical, chemical and microbial parameters of water quality among upstream, basin and downstream of Degala Basin over six months period (March to August 2015) in order to bridge the information on its limnology and microbial characteristic differences to assess its physico-chemical and microbial changes. Dissolved Oxygen, pH, EC, TDS, Na, K, Cl - , total hardness, C a and Mg hardness, NO 3 , total alkalinity, SO 4 with bacteriological parameters were analyzed. The results revealed that the conditions of this dam in different sampling sites were fluctuated in physico-chemical parameters among both sites with high significant relationship for both (EC, TDS, chloride, Na, K, Ca hardness, total alkalinity, nitrate and DO) with low significant relation for both (pH, total hardness, Mg hardness and Sulfate) at (p≤0.05 level). All water samples from all sampling sites showed contamination with bacterial cells that’s due to open area and draining many waste disposals thr ough stream branches that drain their water to upstream river and draining municipal waste water of Degala town through basin and downstream water bodies directly. Copy Right, IJAR, 2016,. All rights reserved. Introduction:- Water plays a key role in different vital activities and is inevitable for all living organisms as it has a great social and economical value ultimately affecting human life. Water is extensively used for irrigation, industrial development, hydro electrical generations, fisheries, human life survival and for domesticated animals. Hence physico- chemical analysis is of prime importance to assess the quality of water for its best usage and also to know the pollution load on receiving water bodies. (Kesre., et al 2011). Dams, built to change natural flow regimes, are one of the most significant human interventions in the hydrological cycle and they can result in post-impoundment phenomena that are specific to reservoirs and not natural lakes. The size of the dam, its location in the river system, its geographical location with respect to altitude and latitude, the detention time of the water and the source(s) of the water all influence the water quality (Bhatnagar, et al. 2013). Water pollution is an acute problem in all the major rivers and dams and water is known to contain a large numbers of chemical elements, the interactions of both the physical and chemical properties of water play a significant role in composition, distribution and abundance of aquatic organisms (Mustapha and Omotosho, 2005). The Degala Basin is about 35 km to the northeast of Erbil city (Fig.1). The main stream that drained to it is composed of two branches which are intermittent. The watershed has a kidney shape. At the outlet there are several