Water Quality Indices and GIS-based evaluation of a decadal groundwater quality

The water quality data of fixed 44 wells were monitored during post- and pre-monsoon season 2005–2013 of Kanchipuram district of state Tamil Nadu, India. Water Quality Indices (WQIs) methodology was applied to categorize groundwater on the basis of rating. In total, 13 groundwater quality parameters: calcium (Ca2+), magnesium (Mg2+), sodium (Na+), potassium (K+), bicarbonate (HCO3 −), nitrate (NO3 −), chloride (Cl−), fluoride (F−), sulphate (SO4 2−), total hardness (TH), total dissolved solids (TDS), hydrogen ion concentration (pH) and electrical conductivity (EC) were taken for statistical analysis. Three different WQI models were computed using a decadal physicochemical water quality data mainly for drinking (WQI1 and WQI2) and irrigation (WQI3) need. The WQIs variability thematic maps were generated in the Geographical Information System environment through ArcGIS software. These spatial distribution maps of WQI provide a detailed overview. The work outlined that the groundwater of the area is impaired by the anthropogenic activities and needs proper management plan to control further contamination and pollution of the groundwater of the area. Further, the groundwater of few monitoring wells needs a proper treatment before its consumptive uses. The alternative water supply should be provided to local inhabitants for daily uses