Assessment of Water Quality in the Shatt Al-Hillah River

Shatt Al-Hillah River, a tributary of the Euphrates River that passes through the Babylon Governorate, which is located in the central part of Iraq, flows through the governorates of Al-Hillah and Al-Diwaniyah. The river is 100 kilometres long overall, and it serves as the primary water source for the cities along its length. As a result, the river's quality must be constantly monitored. In this research, a method was used to utilise a weighted arithmetic water quality index (WOI): using this technique a single water level quality value can thus be created from the enormous amounts of water quality data available. As it is based on the use of fundamental water characterisation factors, the WQI can be utilised as a guideline for the classification of surface water, covering a broad variety of water quality parameters that may otherwise be expensive and time-consuming to calculate in order to accurately reflect water quality. Recent years have thus seen widespread use of the WQI approach to assessing aquatic ecosystems, and it has been recognised as among the most effective approaches for educating the general public and policymakers with regard to patterns in water quality. To enable efficient water quality treatment, the WQI can be utilised to highlight occurrences of both inorganic and organic water contaminants: the goal of the current study was thus to assess and discuss water quality in light of the inherent properties and seasonal changes affecting surface water in the selected system to create a specific WQI that can be integrated with a geographic information system (GIS) to determine the locations with optimum water quality via data mapping. Using previously collected data for the period 2017 to 2021 across two seasons each year, surface water samples were thus examined for a variety of physiochemical characteristics, including hydrogen potential (pH), electrical conductivity (EC), total dissolved solids (TDS), sulphate (SO4-2), chloride anions (Cl-), and nitrates (NO3-1). The water samples most suitable for drinking, aquatic life and irrigation were found at station 1, at Shatt Al-Hillah, with a WQI value of 8.322, while the results showed that the water quality ranged from good to unsuitable (WQI=124.99) at station 4, based on weighted calculations. This highlights considerable disparities between the first and fourth stations. The remaining WQI values were 23.0629 and 42.336 for stations 2 and 3, respectively, which are considered excellent.