Statistical analysis and physicochemical characteristics of groundwater ‎quality parameters: a case study

The assessment of groundwater quality was carried out by taking the shallow wells samples near the bank of River Indus at the downstream Kotri barrage; the study area covers the arid region of Hyderabad, Sindh. The space occupied by the wells was about 1-2 km used for the quantification of geochemical characteristics of the shallow aquifer that lies on the left side of the river. A total of 13 groundwater samples were collected during pre-monsoon and post-monsoon seasons. All the groundwater samples were examined for the characterisation of physicochemical parameters such as Total Dissolved Solids ranged from 320 mg/l to 4011 mg/l, Total Hardness ranged from 120 mg/l to 1320 mg/l, Chloride ranged from 160 mg/l to 2260 mg/l, Sulphate ranged from 61 mg/l to 777 mg/l, pH ranged from 6.9 to 8.1. The findings of the study demonstrate the presence of high quantity physicochemical parameters at a shallow aquifer in contrast to guidelines values by the World Health Organization (WHO) for drinking water. Besides, the T-value was applied to check the variation in pre- and post-monsoon results between parameters, which found significant for chloride 2.701 with p-value 0.031, for fluoride 3.039 with p-value 0.019 and for iron 2.957 with p-value 0.021. Moreover, Correlation coefficients among different parameters were determined which showed that as the correlations between parameters become weaker it also becomes insignificant. An attempt has been made to develop linear regression equations to predict the concentration of water quality constituents. A significantly positive correlation at 1 and 5% found between many parameters. The total hardness with 0.969, chloride with 0.988, and sulphate with 0.994 values were found significant using the conventional level of significance (0.05). However, no apparent changes were visualised in the quality of water during the onset of pre- and post-monsoon seasons over the year.