Comparative Study of Conventional Groundwater Quality Results with WQI Technique: A Case Study of Surjani Town, Karachi, Pakistan

  • Adnan Khan Department of Geology, University of Karachi, Pakistan
  • Aasma Khan Department of Chemistry, University of Karachi, Pakistan
  • Bisma Naz Department of Geology, University of Karachi, Pakistan
  • Rukhsar Rukhsar Department of Geology, University of Karachi, Pakistan
Keywords: Groundwater Quality, Quality Rating Score (Qn), Unit weight (Wn), Weighed Arithmetic Index, WQI, Anthropogenic Activity, Surjani Town


Present study is aimed to calculate the water quality index (WQI) of Surjani Town by using weighted arithmetic index method to assess its suitability for drinking purpose. For calculating WQI, 12 parameters (pH, TDS, EC, Hardness, Na, Ca, K, Mg, HCO3, SO4, NO3 and Cl) have been taken into account. Except pH, all physicochemical parameters are exhibiting the maximum prominence in WQI quality rating scale (Qn) which suggests that groundwater is highly polluted. The computed value of water quality index (WQI= 331.62) is also found to be high which is comparable with enormously high concentrations of physicochemical parameters that are violating the WHO admissible limit for drinking purpose. Results revealed that the groundwater is under the influence of anthropogenic activity from nearby Jam Chakro solid waste dumping site. It is concluded that groundwater is highly deteriorated which is immensely inappropriate for drinking purpose according to WQI rating score.


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