Open AccessDissolved Oxygen Sag Curve for Diyala River at Baquba City
Author(s) -
Muhanad Mohammed Abbas
Publication year - 2021
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/1076/1/012117
Subject(s) - biochemical oxygen demand , environmental science , oxygen , hydrology (agriculture) , pollution , water quality , limiting oxygen concentration , chemical oxygen demand , environmental engineering , wastewater , geology , chemistry , ecology , geotechnical engineering , biology , organic chemistry
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.