Assessment study of water quality index (WQI) for Shatt Al-arab River and its branches, Iraq

Abstract

Shatt Al-Arab River (in Basrah province South of Iraq) is approximately 192 km long. It plays a key role in providing water for domestic purposes, irrigation, manufacturing, in addition to shipment. Recently the river suffers from increasing pollution, due to wastes from industries, domestic sewage and agricultural activities that find their way into water sources and result in large scale deterioration of water quality. Investigating the river size and significance, becomes necessary to perform a study to understand the water quality of this river that is considered by some experts as one of the most contaminated in Iraq. This work uses the Water Quality Index (WQI) to describe the pollution level of the river and by using Geographic Information System (GIS) to create WQI map. This study also determines the critical pollutants affecting the river water quality throughout its course. WQI has been formulated making use of several water quality parameters such as pH, temperature, Dissolved Oxygen (DO), Biological Oxygen Demand（BOD5), Chemical Oxygen Demand（COD）, Nitrate (NO3-2), Phosphate (PO4-3), Total Dissolved Solids (TDS), Total Suspended Solids (TSS), Turbidity (Tur), and Electrical Conductivity (E.C) which were measured at 37 sites along the river. Bad water quality was observed at the sites of the river branches, near the center of Basrah governorate. Furthermore, it was discovered that the main reason for river pollution was due to the high sewage water discharged into the river, especially river branches and illegal discharges of industrial effluent and sewage.

Impact of COVID-19 lockdown on the water quality of the Damodar River, a tributary of the Ganga River in West Bengal

“…The water quality is divided into five classes (Table: S2) and considered very bad (0–25), bad (26–50), medium (51–70), good (71–90), and excellent (91–100) (Hamdan et al 2018 ).…”

The use of multivariate statistical techniques in the assessment of river water quality

“…The concentrations of TDS and Turbidity, greatly increase in the downstream direction (Table 1). The reported of mean values for TDS concentrations which include those acquired in other studies of the Shatt Al-Arab River basins in the study area, as reported by [23,41]. The mean values of the Alkalinity (Alk) (154.04 ppm) were actually above the WHO limits (up to 10 ppm) as shown in Table 1.…”

Assessment of Shatt Al-Arab Water Quality Using CCME/WQI Analysis in Basrah City of South Iraq

“…Water quality was found to be poor towards the governorate's center, along the river forks. Furthermore, it was determined that high sewage water discharged into the river, particularly river branches, as well as illegal industrial effluent and sewage discharges, were the primary causes of river pollution [13]. WQI and GIS software were used to water quality assessment along Tigris River in Iraq.…”