The water quality data is required to be analyzed and primarily average values of Biochemical Oxygen Demand (BOD) and Faecal Coliform (FC) need to be estimated. Then, based on the total score estimated for the parameters BOD (weightage- 70 %) and FC (Weightage- 30 %), the monitoring location is identified as ‘polluted’ location. The polluted locations in a continuous sequence are defined as ‘polluted river stretch’, if the distance between two monitoring locations is less than 10 KMs. However, actual self-purification distance need to be estimated based on the requisite input parameters.The monitoring locations may be prioritized in five classes from Priority I to V i.e., critically polluted to non-polluted. Priority –I indicates ‘critically polluted’; Priority-II indicates ‘severely polluted’; Priority-III indicates ‘moderately polluted’, Priority-IV indicates ‘less polluted’ and Priority –V indicates ‘non-polluted’.
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