Abstract
The water pollution is one of the major environmental problems that which suffered in rivers at Diyala governorate when the untreated waste or partially treated is disposed to rivers. In this study the effect of five sources of raw waste water distributed along Diyala River on the dissolved oxygen sag curve behavior was investigated for selected reach of river when passing Baquba city in Iraq. Dissolved oxygen sag curve tested by using Streeter and Phelps model during summer season Jun, 2018. The study results showed that there was an accumulative effect by decreasing in dissolved oxygen due to these five sources. The dissolved oxygen in the river being below 4 mg/L after the fifth source and continues for (99.4 Km) distance, this point located before river mouth with Tigris River by about 3.4 Km. Dissolved oxygen declined to its critical value after 45Km from first source with maximum deficit. According to the model calculation, Diyala River decants in Tigris River with low limit of dissolved oxygen by about 4.1 mg/L if there were no another sources downstream the observed sources and before achieving its self purification required distance. Also, biochemical oxygen demand was greater than 4 mg/L before river meeting the sources and increased gradually to be greater than 10 mg/L after the fifth source and the temperature increased by about 4 °C.
Highlights
The rivers consider in the foreword of the important surface water sources and till impended by pollutions through disposing different types of untreated or partially treated wastes such as domestic, municipal, industrial, and agricultural waste with high organic content
The high organics effluent represents by untreated wastes which discharges to rivers can cause apparent increase in the biochemical oxygen demand (BOD5) levels
The results showed there were multi points of raw waste water disposed through bypass and outfalls of AL Rustimiyah waste water treatment plant and heavily pollution occurred at this reach of Diyala River [4]
Summary
The rivers consider in the foreword of the important surface water sources and till impended by pollutions through disposing different types of untreated or partially treated wastes such as domestic, municipal, industrial, and agricultural waste with high organic content. These effluent changes the behavior of dissolved oxygen (D.O) and biochemical oxygen demand (BOD5) with its adversely effect on the water life [1]. This change needs large time and distance to permit the river self purification to occur [2]. The results showed there were multi points of raw waste water disposed through bypass and outfalls of AL Rustimiyah waste water treatment plant and heavily pollution occurred at this reach of Diyala River [4]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
