This third edition of report on "water quality hotspots in rivers of India” is based on the data of 10 nos. of water quality parameters observed during 2010-2020 at 588 water quality monitoring stations out of 764 stations of CWC. The eight parameters: pH, Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD) and Total Coliform (TC), Free Ammonia (NH3-N), Electrical Conductivity (EC), Boron (B),Sodium Adsorption Ratio (SAR) are required for classification based on uses defined by CPCB. Fluoride (F¯) and Sulphate (SO4-2) are among the parameters of BIS specification for drinking water (BIS: 10500:2012).These parameters are important constituents defining the quality of river water in surface water. Therefore, presence of these parameters in river water beyond the permissible limit in the absence of alternate source has been considered as river water quality hot spots.
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